PURPOSE: While the association between diet quality and mortality has been previously demonstrated, the association between frailty and diet quality has not been evaluated well. This study aimed to investigate the association between diet quality and prevalence of both physical and comprehensive frailty, using two validated tools, in a community-based cohort of older adults. METHODS: We conducted cross-sectional analyses using baseline data of 7022 participants aged ≥ 65 years in the Kyoto-Kameoka study. Diet quality was assessed by calculating the adherence scores to the Japanese Food Guide Spinning Top using a validated questionnaire; the participants were stratified into quartile groups based on these scores. Physical and comprehensive frailty was assessed using the Fried phenotype model-based Frailty Screening Index and the Kihon Checklist, respectively. Multivariable logistic regression and the restricted cubic spline model were used to calculate odds ratios (ORs) and their 95% confidence intervals (CIs) for associations between adherence scores and frailty prevalence. RESULTS: Higher adherence scores signified a higher intake of vitamin C, vegetables, dairy products, and fruits. Physical and comprehensive frailty prevalence was 14.2 and 35.8%, respectively. In a multivariable adjusted model, compared with the bottom adherence score quartile, the top quartile was associated with lower ORs of physical (OR 0.64; 95% CI 0.52-0.80) and comprehensive frailty (OR 0.60; 95% CI 0.51-0.71). These relationships were similar to results in the spline model. CONCLUSIONS: This study shows an inverse dose-response relationship between diet quality and prevalence of both physical and comprehensive frailty in older adults.

Dietary ω3 fatty acids have important health benefits and exert their potent bioactivity through conversion to lipid mediators. Here, we demonstrate that microbiota play an essential role in the body's use of dietary lipids for the control of inflammatory diseases. We found that amounts of 10-hydroxy-cis-12-cis-15-octadecadienoic acid (αHYA) and 10-oxo-cis-12-cis-15-octadecadienoic acid (αKetoA) increased in the feces and serum of specific-pathogen-free, but not germ-free, mice when they were maintained on a linseed oil diet, which is high in α-linolenic acid. Intake of αKetoA, but not αHYA, exerted anti-inflammatory properties through a peroxisome proliferator-activated receptor (PPAR)γ-dependent pathway and ameliorated hapten-induced contact hypersensitivity by inhibiting the development of inducible skin-associated lymphoid tissue through suppression of chemokine secretion from macrophages and inhibition of NF-κB activation in mice and cynomolgus macaques. Administering αKetoA also improved diabetic glucose intolerance by inhibiting adipose tissue inflammation and fibrosis through decreased macrophage infiltration in adipose tissues and altering macrophage M1/M2 polarization in mice fed a high-fat diet. These results collectively indicate that αKetoA is a novel postbiotic derived from α-linolenic acid, which controls macrophage-associated inflammatory diseases and may have potential for developing therapeutic drugs as well as probiotic food products.

Previous cohort study reported that high physical activity was associated with a low risk of self-reported hearing loss in women. However, no studies have examined the association between physical activity and the development of hearing loss as measured using an objective assessment of hearing loss in men and women. Here we used cohort data to examine the association between leisure-time physical activity and incidence of objectively assessed hearing loss in men and women. Participants included 27,537 Japanese adults aged 20-80 years without hearing loss, who completed a self-administered physical activity questionnaire between April 2001 and March 2002. The participants were followed up for the development of hearing loss as measured by audiometry between April 2002 and March 2008. During follow-up, 3691 participants developed hearing loss. Compared with the none physical activity group, multivariable adjusted hazard ratios for developing hearing loss were 0.93 (95% confidence interval, 0.86-1.01) and 0.87 (0.81-0.95) for the medium (<525 MET-min/week) and high (≥525 MET-min/week) physical activity groups, respectively (P for trend = .001). The magnitude of risk reduction was slightly greater in vigorous-intensity activity than in moderate-intensity activity (P for interaction = .01). Analysis by sound frequency showed that the amount of physical activity was inversely associated with high frequency hearing loss development (P for trend <.001), but not with low frequency hearing loss development (P for trend = .19). Higher level of leisure-time physical activity was associated with lower incidence of hearing loss, particularly for vigorous-intensity activities and high sound frequencies.

Human skeletal muscle fiber is heterogenous due to its diversity of slow- and fast-twitch fibers. In human, slow-twitched fiber gene expression is correlated to MOTS-c, a mitochondria-derived peptide that has been characterized as an exercise mimetic. Within the MOTS-c open reading frame, there is an East Asian-specific m.1382A>C polymorphism (rs111033358) that changes the 14th amino acid of MOTS-c (i.e., K14Q), a variant of MOTS-c that has less biological activity. Here, we examined the influence of the m.1382A>C polymorphism causing MOTS-c K14Q on skeletal muscle fiber composition and physical performance. The myosin heavy chain (MHC) isoforms (MHC-I, MHC-IIa, and MHC-IIx) as an indicator of muscle fiber composition were assessed in 211 Japanese healthy individuals (102 men and 109 women). Muscular strength was measured in 86 physically active young Japanese men by using an isokinetic dynamometer. The allele frequency of the m.1382A>C polymorphism was assessed in 721 Japanese athletes and 873 ethnicity-matched controls. The m.1382A>C polymorphism genotype was analyzed by TaqMan SNP Genotyping Assay. Individuals with the C allele of the m.1382A>C exhibited a higher proportion of MHC-IIx, an index of fast-twitched fiber, than the A allele carriers. Men with the C allele of m.1382A>C exhibited significantly higher peak torques of leg flexion and extension. Furthermore, the C allele frequency was higher in the order of sprint/power athletes (6.5%), controls (5.1%), and endurance athletes (2.9%). Additionally, young male mice were injected with the MOTS-c neutralizing antibody once a week for four weeks to mimic the C allele of the m.1382A>C and assessed for protein expression levels of MHC-fast and MHC-slow. Mice injected with MOTS-c neutralizing antibody showed a higher expression of MHC-fast than the control mice. These results suggest that the C allele of the East Asian-specific m.1382A>C polymorphism leads to the MOTS-c K14Q contributes to the sprint/power performance through regulating skeletal muscle fiber composition.

In older adults, the quantitative decline of the quadriceps femoris is associated with the augmentation of difficulty in the execution of a stand-up task. However, it is unclear whether the cross-sectional areas (CSAs) of individual thigh muscles differ between older adults who can stand up from a 40-cm-height chair on a single leg and those who cannot. To investigate this, the present study determined the CSAs of individual mid-thigh muscles in 67 Japanese women aged 60-77 years by using a magnetic resonance imaging method. Participants were asked to stand up from a 40-cm-height chair on a single leg, and those who could and could not stand up without leaning back and maintain a standing posture for 3 seconds on a single leg were allocated into the successful group (SG, n = 40) and unsuccessful group (USG, n = 27), respectively. Only the CSA of the adductors (sum of the adductor longus and adductor magnus) was significantly smaller in USG compared to SG. When CSA was expressed relative to the two-third power of body mass, the values for the four heads of the quadriceps femoris and biceps femoris long head, as well as the adductors, were significantly lower in USG than in SG. The current results indicate that in terms of the value relative to body mass, the reduced CSAs of the adductors and biceps femoris long head, as well as the four heads of the quadriceps femoris, are associated with the failure of attempts to stand up from a 40-cm-height chair on a single leg in older women. This may be due to the anatomical function of the two muscle groups, which contributes to hip extension movement involved in transitioning from a sitting position to a standing position during the stand-up task.

Background: Many cross-sectional studies have identified modifiable factors such as dietary intake, physique, and physical activity associated with diet quality but were unable to determine how a specific individual's diet quality changes with these factors. These relationships may vary depending on an individual's dietary intake. We aimed to determine the association between temporal changes in diet quality and concurrent changes in dietary intake, body mass index (BMI), and physical activity according to the diet quality trajectory pattern. Methods: This longitudinal prospective study included 697 Japanese adults aged 26-85 years, at baseline, with available data from at least two dietary intake surveys (4,118 measurements). Dietary intake and physical activity were evaluated using validated dietary questionnaires and a triaxial accelerometer. Diet quality was calculated using the Nutrient-Rich Food Index 9.3 (NRF9.3), while physical activity was calculated based on the duration of activity performed at each level of intensity (sedentary, light, moderate, and vigorous). Body mass index was calculated from the measured height and weight. Statistical analyses involved latent class growth models (LCGM) and random-effect panel data analysis. Results: During a mean follow-up period of 6.8 years, NRF9.3 scores were assessed, on average, 5.4 times in men and 6.1 times in women. Based on the NRF9.3 score, three separate trajectory groups-"low-increasing," "medium-increasing," and "high-stable"-among individuals aged 26-90 years were identified using LCGM. In the multivariate analysis, the NRF9.3 score trajectory was positively associated with intake of energy, protein, dietary fiber, vitamins A and C, magnesium, and food items, such as fruits and vegetables, and was negatively associated with BMI and the intake of added sugar, saturated fats, sodium, and food items, such as meat and sugar and confectioneries, even after adjusting for covariates. These relationships displayed heterogeneity across the identified NRF9.3 score trajectory groups. In the low-increasing group, an inverse relationship was observed between sedentary behavior and NRF9.3 score trajectory. Conclusions: We identified modifiable factors associated with temporal changes in diet quality across a wide age range; however, these factors may vary according to the diet quality trajectories. Our findings may help develop effective strategies for improving diet quality, according to the trajectory of diet quality.

Barley is a grain rich in β-glucan, a soluble dietary fiber, and its consumption can help maintain good health and reduce the risk of metabolic disorders, such as dyslipidemia. However, the effect of barley intake on the risk of dyslipidemia has been found to vary among individuals. Differences in gut bacteria among individuals may be a determining factor since dietary fiber is metabolized by gut bacteria and then converted into short-chain fatty acids with physiological functions that reduce the risk of dyslipidemia. This study examined whether gut bacteria explained individual differences in the effects of barley intake on dyslipidemia using data from a cross-sectional study. In this study, participants with high barley intake and no dyslipidemia were labeled as "responders" to the reduced risk of dyslipidemia based on their barley intake and their gut bacteria. The results of the 16S rRNA gene sequencing showed that the fecal samples of responders (n = 22) were richer in Bifidobacterium, Faecalibacterium, Ruminococcus 1, Subdoligranulum, Ruminococcaceae UCG-013, and Lachnospira than those of non-responders (n = 43), who had high barley intake but symptoms of dyslipidemia. These results indicate the presence of certain gut bacteria that define barley responders. Therefore, we attempted to generate a gut bacteria-based responder classification model through machine learning using random forest. The area under the curve value of the classification model in estimating the effect of barley on the occurrence of dyslipidemia in the host was 0.792 and the Matthews correlation coefficient was 0.56. Our findings connect gut bacteria to individual differences in the effects of barley on lipid metabolism, which could assist in developing personalized dietary strategies.

BACKGROUND: In an effort to increase people's adherence to active lifestyles, contemporary physical activity (PA) guidelines now include low-dose PA. METHODS: PA was evaluated in 583 participants of the Nutritional and Physical Activity Intervention Study (NEXIS) cohort (30-65 years old); 349 inactive participants (MVPA, 2.7 ± 1.0 MET-h/day) were randomly assigned to the intervention or control groups, and 235 active participants participated in follow-up visits. The intervention aimed to increase MVPA and comprised five brief counseling sessions over 1 year. The 1-year target for the participant was increasing their step-count to 10,000 steps/d or +3000 steps/d, relative to the baseline score. The counseling sessions were designed to stimulate progressive changes in physical behaviors by recommendations promoting small and/or light-intensity bouts of PA. PA was measured at baseline, the end of the intervention, and 1 year after the intervention ended. Additionally, several nutrition, health, and fitness parameters were measured. RESULTS: Participants in the intervention group significantly increased their step-count from 8415 ± 1924 at baseline to 9493 ± 2575 at the end of the 1-year period. During the same period, MVPA significantly increased by 0.9 MET-h. The daily time spent in ≥ 3, ≥ 4 and ≥ 5 MET activities increased by 11, 6, and 3 min, respectively. This increase in PA remained observable 1 year after intervention concluded. The active group maintained higher physical activity levels throughout the two years. The intervention group showed smaller energy intakes at the end of the 2-year period. Significant correlations were noted between the 1-year change in MVPA and the change in resting heart rate (r =  - 0.22), and between the 2-year change in MVPA and the change in waist circumference (r =  - 0.08) and peak oxygen consumption capacity (r = 0.23) in the intervention group only. CONCLUSIONS: A prolonged and progressive PA intervention promoting small bouts of light-to-moderate PA may be used in healthy, not-optimally-active people to increase PA beyond the strict period of the intervention. Further studies are necessary to understand whether low-dose PA messages can be effective in initiating a progressive increase toward larger amounts of PA. TRIAL REGISTRATION: Clinical Trials.gov, NCT00926744, retrospectively registered.

BACKGROUND & AIMS: A limited number of studies have developed simple anthropometric equations that can be implemented for predicting muscle mass in the local community. Several studies have suggested calf circumference as a simple and accurate surrogate maker for muscle mass. We aimed to develop and cross-validate a simple anthropometric equation, which incorporates calf circumference, to predict appendicular skeletal muscle mass (ASM) using dual-energy X-ray absorptiometry (DXA). Furthermore, we conducted a comparative validity assessment of our equation with bioelectrical impedance analysis (BIA) and two previously reported equations using similar variables. METHODS: ASM measurements were recorded for 1262 participants (837 men, 425 women) aged 40 years or older. Participants were randomly divided into the development or validation group. Stepwise multiple linear regression was applied to develop the DXA-measured ASM prediction equation. Parameters including age, sex, height, weight, waist circumference, and calf circumference were incorporated as predictor variables. Total error was calculated as the square root of the sum of the square of the difference between DXA-measured and predicted ASMs divided by the total number of individuals. RESULTS: The most optimal ASM prediction equation developed was: ASM (kg) = 2.955 × sex (men = 1, women = 0) + 0.255 × weight (kg) - 0.130 × waist circumference (cm) + 0.308 × calf circumference (cm) + 0.081 × height (cm) - 11.897 (adjusted R2 = 0.94, standard error of the estimate = 1.2 kg). Our equation had smaller total error and higher intraclass correlation coefficient (ICC) values than those for BIA and two previously reported equations, for both men and women (men, total error = 1.2 kg, ICC = 0.91; women, total error = 1.1 kg, ICC = 0.80). The correlation between DXA-measured ASM and predicted ASM by the present equation was not significantly different from the correlation between DXA-measured ASM and BIA-measured ASM. CONCLUSIONS: The equation developed in this study can predict ASM more accurately as compared to equations where calf circumference is used as the sole variable and previously reported equations; it holds potential as a reliable and an effective substitute for estimating ASM.

Evidence on the effects of a community-wide intervention (CWI) on population-level physical activity (PA), especially in the long term, is limited. Therefore, we evaluated the five-year effect of CWI on promoting PA through information dissemination, education, and community support primarily targeting older adults, by incorporating Japanese guidelines, in Fujisawa City, from 2013. To assess the effect of the whole-city intervention, we distributed questionnaires in 2013, 2015, and 2018 to three independent random samples of 3,000 community-dwelling adults (aged ≥ 20 years) using a quasi-experimental study design. Three separate samples responded to the survey (41% at baseline, 46% at the two-year mark, and 48% at the five-year follow-up). The primary outcome was change in PA participation. At the five-year follow-up, PA (median: 120 minutes/day) was significantly higher than at baseline (86 minutes/day) and the two-year follow-up (90 minutes/day). The results of the multivariate analysis indicated that PA among older adults-the primary target population of the CWI-increased significantly at the five-year follow-up, compared to those aged 20-64 (mean difference of change between groups: 14.7 minutes/day, P= 0.029). Among older adults, PA was significantly lower in those with poorer perceived economic status than in their more well-off counterparts at the two-year follow-up (P= 0.003); however, there was no significant difference at the five-year follow-up (P= 1.000). There was a positive interaction between group and period (mean difference of change between groups: 40.9 minutes/day, P= 0.001). In conclusion, the five-year CWI targeting older adults, incorporating national guidelines, improved population-level PA.

BACKGROUND: The Escherichia coli strain that is known to produce the genotoxic secondary metabolite colibactin is linked to colorectal oncogenesis. Therefore, understanding the properties of such colibactin-positive E. coli and the molecular mechanism of oncogenesis by colibactin may provide us with opportunities for early diagnosis or prevention of colorectal oncogenesis. While there have been major advances in the characterization of colibactin-positive E. coli and the toxin it produces, the infection route of the clb + strain remains poorly characterized. RESULTS: We examined infants and their treatments during and post-birth periods to examine potential transmission of colibactin-positive E. coli to infants. Here, analysis of fecal samples of infants over the first month of birth for the presence of a colibactin biosynthetic gene revealed that the bacterium may be transmitted from mother to infant through intimate contacts, such as natural childbirth and breastfeeding, but not through food intake. CONCLUSIONS: Our finding suggests that transmission of colibactin-positive E. coli appears to be occurring at the very early stage of life of the newborn and hints at the possibility of developing early preventive measures against colorectal cancer.

Lifestyle changes during the coronavirus disease (COVID-19) lockdown have been previously examined, but there is limited understanding about changes after such restrictions were lifted. This study examines changes in lifestyle habits and body weight among the Japanese population with regard to the length of at-home hours both during (April to May) and after (September) the nationwide stay-at-home request compared to those before the COVID-19 pandemic (January 2020). An online survey was conducted in September 2020 involving 10,000 Japanese survey monitors, selected according to population distribution. During the stay-at-home request, 34% participants extended their at-home hours. More respondents in the group with extended at-home hours experienced an increase or decrease in total physical activity, snacking, food intake, alcohol drinking, and body weight than those in the group with nonextended at-home hours. Some of these changes had a trend according to age. The prevalence of most of these changes decreased when at-home hours returned to normal after the stay-at-home request period; however, increased alcohol consumption and increased or decreased body weight persisted. Our findings suggest that close monitoring for further health outcomes and age-appropriate measures to encourage favorable health behaviors is needed.

BACKGROUND: Colibactin-producing Escherichia coli containing polyketide synthase (pks+ E. coli) has been shown to be involved in colorectal cancer (CRC) development through gut microbiota analysis in animal models. Stool status has been associated with potentially adverse gut microbiome profiles from fecal analysis in adults. We examined the association between stool patterns and the prevalence of pks+ E. coli isolated from microbiota in fecal samples of 224 healthy Japanese individuals. RESULTS: Stool patterns were determined through factorial analysis using a previously validated questionnaire that included stool frequency, volume, color, shape, and odor. Factor scores were classified into tertiles. The prevalence of pks+ E. coli was determined by using specific primers for pks+ E. coli in fecal samples. Plasma and fecal fatty acids were measured via gas chromatography-mass spectrometry. The prevalence of pks+ E. coli was 26.8%. Three stool patterns identified by factorial analysis accounted for 70.1% of all patterns seen (factor 1: lower frequency, darker color, and harder shape; factor 2: higher volume and softer shape; and factor 3: darker color and stronger odor). Multivariable-adjusted odds ratios (95% confidence intervals) of the prevalence of pks+ E. coli for the highest versus the lowest third of the factor 1 score was 3.16 (1.38 to 7.24; P for trend = 0.006). This stool pattern exhibited a significant positive correlation with fecal isobutyrate, isovalerate, valerate, and hexanoate but showed a significant negative correlation with plasma eicosenoic acid and α-linoleic acid, as well as fecal propionate and succinate. No other stool patterns were significant. CONCLUSIONS: These results suggest that stool patterns may be useful in the evaluation of the presence of tumorigenic bacteria and fecal fatty acids through self-monitoring of stool status without the requirement for specialist technology or skill. Furthermore, it may provide valuable insight about effective strategies for the early discovery of CRC.

BACKGROUND: The Asian Working Group for Sarcopenia (AWGS) 2019 recommended the use of dual-energy X-ray absorptiometry (DXA) or bioelectrical impedance analysis (BIA) to assess appendicular lean mass (ALM). AWGS, European Working Group on Sarcopenia in Older People 2 (EWGSOP2), Foundation for the National Institutes of Health Sarcopenia Project (FNIH), and International Working Group on Sarcopenia (IWGS) reported different cutoff values for sarcopenia. We aimed to validate these cutoff values in a Japanese population using DXA and two different devices of segmental multi-frequency BIA (MF-BIA). METHODS: We examined the data of Japanese individuals aged 18-86 years using the DXA (n = 756) and two 8-electrode MF-BIA devices (InBody and TANITA MC) (n = 1884). To validate these cutoff values, we used a population aged 18-40 years, and calculated the 95% confidence intervals (CIs) of [mean-2SD]. RESULTS: In DXA, the 95%CIs of [mean-2SD] for ALM/Ht2 were 5.2-5.8 and 6.6-7.3 kg/m2 in women and men, respectively. The AWGS (<5.4 in women and <7.0 in men), and IWGS (≤5.67 in women and ≤7.23 in men) cutoffs were acceptable. Regarding TANITA MC, the 95%CIs of [mean-2SD] for ALM/Ht2 were 5.6-6.0 and 6.9-7.4 kg/m2 in women and men, respectively. The AWGS (<5.7 in women and <7.0 in men), EWGSOP2 (<6.0 in women and <7.0 in men), and IWGS cutoffs were acceptable. Regarding InBody, the 95%CIs of [mean-2SD] for ALM/Ht2 were 4.8-5.2 and 6.4-6.8 kg/m2 in young women and men, respectively. All cutoff values were too high compared to those measured by InBody. InBody and TANITA MC were highly correlated (P < 0.001), but the values by InBody were significantly lower than those by TANITA MC or DXA. Using Yamada's equation for InBody raw data, the AWGS, EWGSOP2, or IWGS cutoffs were acceptable. The BMI-adjusted muscle mass cutoff values were <0.60 and <0.82 m2 in women and men, respectively. We also obtained the 20th percentile in older adult population (ALM/Ht2 , <6.2 in women and <7.5 in men for TANITA MC; <5.4 in women and <7.0 in men for InBody). CONCLUSIONS: The AWGS and IWGS cutoffs were valid for DXA, and the AWGS, IWGS, and EWGSOP2 cutoffs were valid for TANITA MC in Japanese population. Because the prevalence of sarcopenia is too low particularly in women when using those criteria, the 20th percentile might be a good alternative criteria. If the ALM original InBody values are used, the cutoffs should be <5.0 kg/m2 in women and <6.6 kg/m2 in men.

BACKGROUND: Inter-individual variations in gut microbiota composition are observed even among healthy populations. The gut microbiota may exhibit a unique composition depending on the country of origin and race of individuals. To comprehensively understand the link between healthy gut microbiota and host state, it is beneficial to conduct large-scale cohort studies. The aim of the present study was to elucidate the integrated and non-redundant factors associated with gut microbiota composition within the Japanese population by 16S rRNA sequencing of fecal samples and questionnaire-based covariate analysis. RESULTS: A total of 1596 healthy Japanese individuals participated in this study via two independent cohorts, NIBIOHN cohort (n = 954) and MORINAGA cohort (n = 642). Gut microbiota composition was described and the interaction of these microorganisms with metadata parameters such as anthropometric measurements, bowel habits, medical history, and lifestyle were obtained. Thirteen genera, including Alistipes, Anaerostipes, Bacteroides, Bifidobacterium, Blautia, Eubacterium halli group, Faecalibacterium, Fusicatenibacter, Lachnoclostridium, Parabacteroides, Prevotella_9, Roseburia, and Subdoligranulum were predominant among the two cohorts. On the basis of univariate analysis for overall microbiome variation, 18 matching variables exhibited significant association in both cohorts. A stepwise redundancy analysis revealed that there were four common covariates, Bristol Stool Scale (BSS) scores, gender, age, and defecation frequency, displaying non-redundant association with gut microbial variance. CONCLUSIONS: We conducted a comprehensive analysis of gut microbiota in healthy Japanese individuals, based on two independent cohorts, and obtained reliable evidence that questionnaire-based covariates such as frequency of bowel movement and specific dietary habit affects the microbial composition of the gut. To our knowledge, this was the first study to investigate integrated and non-redundant factors associated with gut microbiota among Japanese populations.

Objectives The purpose of this study was to examine the prevalence of frailty and its associated factors in community-dwelling middle-aged and elderly adults in Settsu and Hannan cities, which are located in the north and south of Osaka prefecture, respectively.Methods We conducted a mailed, self-administered, questionnaire survey of individuals aged 40 years and older in Settsu city in 2019 and Hannan city in 2020. There are 10 primary school districts in Settsu city and 8 districts in Hannan city, from each of which 1,000 people were selected according to the age and sex structures of the districts. We included 5,134 individuals from Settsu city and 3,939 individuals from Hannan city. We defined frailty using self-reported questionnaires, the Kihon Checklist (KCL), and Simple Frailty Index (SFI). Multivariate logistic regression analysis was performed for each city to examine the association of frailty with age, sex, body mass index (BMI), family structure, subjective health, economic status, subjective physical fitness, sleeping status, smoking history, alcohol use, meal frequency and awareness of the word "frailty."Results The average age (standard deviation) of participants was 62.7 (12.5) years in Settsu city and 63.4 (12.2) years in Hannan city. The prevalence of frailty by KCL was 18.7% and 17.9% for participants in their 40s, 18.2% and 14.6% for those in their 50s, 17.0% and 15.7% for those in their 60s, 25.4% and 20.8% for those in their 70s, 39.7% and 36.1% for those 80 years and older from Settsu and Hannan cities, respectively. Using SFI, the prevalence of frailty was 16.2% and 13.5% for participants in their 40s, 15.0% and 11.9% for those in their 50s, 12.5% and 10.0% for those in their 60s, 14.6% and 12.3% for those in their 70s, and 24.7% and 22.3% for those aged 80 years and older in Settsu and Hannan cities, respectively. Significant common independent variables associated with frailty as defined using the KCL and SFI in Settsu and Hannan cities were age, subjective health, economic status, subjective physical fitness, sleeping status, and awareness of the word "frailty."Conclusion This study found some participants to be frail as early as their 40s or 50s. Thus, efforts must be made to prevent frailty in working-age populations, including those aged 40 years and older. Six factors were associated with frailty. Longitudinal or interventional studies are required to examine their causal relationships and public health significance.

BACKGROUND: It has been pointed out that prolonged television (TV) viewing is one of the sedentary behaviors that is harmful to health; however, the association between socioeconomic status (SES) and prolonged TV viewing time has not been sufficiently investigated in Japan. METHODS: The study population are the participants of NIPPON DATA2010, which is a prospective cohort study of the National Health and Nutrition Survey 2010 in Japan. They were residents in 300 randomly selected areas across Japan. This study included 2752 adults. SES was classified according to the employment status, educational attainment, living status, and equivalent household expenditure (EHE). Prolonged TV viewing time was defined as more than or equal to 4 h of TV viewing per day. Multivariable logistic regression analyses were conducted to examine the association of SES with prolonged TV viewing time. RESULTS: The mean TV viewing time was 2.92 h in all participants. Of 2752 participants, 809 (29.4%) prolonged TV viewing, and the mean TV viewing time of them was 5.61 h. The mean TV viewing time in participants without prolonged TV viewing time was 1.81 h. The mean TV viewing time was prolonged as age classes increased and significantly longer in aged ≥60 years. Prolonged TV viewing time was associated with not working for all age classes and sexes. Only among women, education attainment and living status were also associated with prolonged TV viewing time. For education attainment, the lower the received years of education, the higher odds ratios (OR) of prolonged TV viewing time. For living status, in women aged <60 years, living with others had a significantly higher OR compared to living with spouse. On the other hand, in women aged ≥60 years, living alone had a significantly higher OR. EHE did not have any significant associations with prolonged TV viewing time. CONCLUSIONS: In a general Japanese population, it should be noted that the association between SES and prolonged TV viewing time differed by age and sex. Particularly, it must draw attention to the prolonged TV viewing in elderly. The intervention in order to shorten TV viewing time needs to consider these attributes.

BACKGROUND: Previous epidemiological studies have demonstrated the prevalence and relationship of various factors associated with sarcopenia in older adults; however, few have examined the status of sarcopenia in middle-aged adults. In this study, we aimed to, 1) evaluate the validity of the finger-circle test, which is potentially a useful screening tool for sarcopenia, and 2) determine the prevalence and factors associated with sarcopenia in middle-aged and older adults. METHODS: We conducted face-to-face surveys of 525 adults, who were aged 40-91 years and resided in Settsu City, Osaka Prefecture, Japan to evaluate the validity of finger-circle test. The finger-circle test evaluated calf circumference by referring to an illustration printed on the survey form. The area under the receiver operating characteristic curves (AUROC) was plotted to evaluate the validity of the finger-circle test for screening sarcopenia and compared to that evaluated by skeletal muscle mass index (SMI) measured using bioimpedance. We also conducted multisite population-based cross-sectional anonymous mail surveys of 9337 adults, who were aged 40-97 years and resided in Settsu and Hannan Cities, Osaka Prefecture, Japan. Participants were selected through stratified random sampling by sex and age in the elementary school zones of their respective cities. We performed multiple logistic regression analysis to explore associations between characteristics and prevalence of sarcopenia. RESULTS: Sarcopenia, defined by SMI, was moderately predicted by a finger-circle test response showing that the subject's calf was smaller than their finger-circle (AUROC: 0.729, < 65 years; 0.653, ≥65 years); such subjects were considered to have sarcopenia. In mail surveys, prevalence of sarcopenia screened by finger-circle test was higher in older subjects (approximately 16%) than in middle-aged subjects (approximately 8-9%). In a multiple regression model, the factors associated with sarcopenia were age, body mass index, smoking status, self-reported health, and number of meals in all the participants. CONCLUSIONS: Sarcopenia, screened by the finger-circle test, was present not only among older adults but also among middle-aged adults. These results may provide useful indications for developing public health programs, not only for the prevention, but especially for the management of sarcopenia. TRIAL REGISTRATION: UMIN000036880, registered prospectively May 29, 2019,  https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000042027.

PURPOSE: The age-associated increase in arterial wall viscosity (AWV) is attenuated by high cardiorespiratory fitness level. However, AWV in endurance-trained athletes have not been determined. We designed a cross sectional study to compare central AWV and compliance between endurance-trained young athletes and age-matched control men. METHODS: Twenty-one endurance-trained men (age 20.7 ± 0.3 years) and 20 age-matched healthy control men (age 21.6 ± 0.4 years) were studied. The common carotid artery was measured noninvasively by tonometry and automatic tracking of B-mode images to obtain instantaneous pressure and diameter hysteresis loops, and we calculated the dynamic carotid arterial compliance, static (effective and isobaric) compliance, and viscosity index. RESULTS: The AWV index in the endurance-trained men was larger than the control peers (2285 ± 181 vs. 1429 ± 124 mmHg·s/mm: P < 0.001). In addition, dynamic and static compliance were not statistically different between both groups. CONCLUSION: The present study indicated that the central AWV in endurance-trained athletes was greater than age-matched healthy control men. We believe that the AWV, as well as arterial compliance, is an important element for assessing vascular adaptation to endurance training.

PURPOSE: This study aimed to examine the association between whole-body or segmental phase angle (PhA) based on bioelectrical impedance analysis (BIA) and aerobic capacity (endurance), complex gait ability, and total fitness age score (FAS). METHODS: A total of 426 community-dwelling older adults (332 women and 94 men) aged 60 to 93 years participated in this study. PhA and appendicular skeletal mass index (ASMI) were obtained by an eight-electrode standing BIA. Aerobic capacity was assessed using the shuttle stamina walk test (SSTw); complex gait ability, using the timed-up-and-go test (TUG). FAS was obtained using the previously validated multi-dimensional equations based on 7-year longitudinal data. SSTw, TUG, and FAS were compared between the low PhA (<4.4° for women and <5.2° for men) and normal PhA groups. Pearson's correlation between PhA and SSTw, TUG, and FAS was determined. Multiple linear regression analysis was conducted using SSTw, TUG, and FAS as dependent variables. Age, sex, height, body mass index (BMI), ASMI, and PhA were entered into the linear model. RESULTS: SSTw and TUG results and FAS were significantly lower in the low PhA group (P < 0.05). PhA was significantly correlated with SSTw, TUG, and FAS (P < 0.001), and leg PhA showed a stronger correlation than whole-body or arm PhA. PhA at 50 kHz had higher correlation coefficients with SSTw, TUG, or FAS compared with PhA at 5 or 250 kHz. Multiple regression analyses indicated that leg PhA at 50 kHz was a significant predictor of SSTw, TUG, and FAS, independent of age, sex, height, BMI, and ASMI. CONCLUSION: Our results indicate that leg PhA is associated with multi-dimensional physical fitness in community-dwelling older adults. PhA is a highly informative biomarker of skeletal muscle and exercise physiology in clinical settings.

目的 ふん便(以下、便)は、我々の食事や栄養状態ならびに腸内細菌叢の特徴を反映し、身体の健康状態や栄養摂取状況を、簡便かつ非侵襲的に評価できるツールであると考えられる。一方で、便を包括的に評価し、簡便かつ客観的に評価する適切なツールに関する検討は十分に行われておらず、日常の排便状況や便性状を的確に把握できる有用な質問票が求められている。習慣的な排便状況(排便回数)や便性状(排便量、色、形状など)を把握するための評価ツールを作成し、排便日誌に基づく排便回数や便性状の記録と比較し内的妥当性を検討した。方法 22から78歳までの成人男女35人(45.2±17.1歳)を解析対象とした。習慣的な便に関する質問票(以下、習慣的便質問票)による最近1ヵ月間における平均的な排便回数、1回あたりの排便量、便の色や形状、便の浮きや腹部膨満感を調査した。この習慣的便質問票の各項目の再現性を検討するため、2回の調査を実施し、再現性を確認した。その後、排便日誌を用いて、毎日の排便時刻や便の性状などを1週間記録した。この排便日誌を基にした排便回数や便性状を内的妥当基準とし、習慣的便質問票により得られた回答を比較した。なお、習慣的便質問票における排便回数は、排便回数がカテゴリー化された回答を選択する選択回答法と数値による自由回答法の2種類で回答した。結果 習慣的便質問票の再現性を検討した結果、全ての項目においてスピアマン順位相関係数の有意な相関(ρ=0.431〜0.911)が認められ、重みづけκ係数においても高い一致度を示した(weighted κ=0.348〜0.841)。また、内的妥当性については、排便日誌による1週間あたりの排便回数と、習慣的便質問票における排便回数の回答を比較すると、自由回答法による1週間あたりの排便回数の方が、選択回答法より高い相関(ρ=0.855)を示した。さらに、便性状については、1週間の排便日誌における便性状の回答の中央値と習慣的便質問票での回答との相関を検討したところ、「便の浮き」を除いて有意な相関が示された(ρ=0.429〜0.800)。結論 本研究で作成した質問票は、習慣的な排便状況や便性状を評価する上で、再現性と内的妥当性が高いことが確認された。(著者抄録)

BACKGROUND: Lower socioeconomic status (SES) may be related to inactivity lifestyle; however, the association between SES and physical inactivity has not been sufficiently investigated in Japan. METHODS: The study population is the participants of NIPPON DATA2010, which is a prospective cohort study of the National Health and Nutrition Survey 2010 in Japan. They were residents in 300 randomly selected areas across Japan. This study included 2,609 adults. Physical activity was assessed by physical activity index (PAI) calculated from activity intensity and time. The lowest tertile of PAI for each 10-year age class and sex was defined as physical inactivity. Multivariable logistic regression analyses were conducted to examine the association of SES (employment status, educational attainment, living status, and equivalent household expenditure (EHE)) with physical inactivity. RESULTS: In the distribution of PAI by age classes and sex, the highest median PAI was aged 30-39 years among men (median 38.6), aged 40-49 years among women (38.0), and median PAI was decreased with increasing age. Multivariable-adjusted model shows that not working was significantly associated with physical inactivity after adjustment for age in all age groups and sexes. Not living with spouse for adult women and elderly men was significantly associated with physical inactivity compared to those who living with spouse. However, neither educational attainment nor EHE had any significant associations with physical inactivity. CONCLUSIONS: The result indicated that physical inactivity was associated with SES in a general Japanese population. SES of individuals need to be considered in order to prevent inactivity lifestyle.

BACKGROUND: The prevention of metabolic syndrome (MetS) is a major public health concern in Japan. The effects of the relationship between eating behavior and nutritional intake on MetS remained unclear. To evaluate nutrition's role in preventing or exacerbating MetS, we examined the associations among eating behavior, nutritional intake, and MetS for the baseline study in the cohort subjects undergone health checkups. METHODS: Four thousand and four hundred forty-seven Japanese men and women were enrolled at the Saku Central Hospital. They received an anthropometric and clinical examination and were assessed for present illness, lifestyle factors such as physical activity, smoking, drinking, and dietary habits at the enrollment. Eating behavior was analyzed by the Sakata's Eating Behavior Questionnaire. Dietary assessment was made using a brief self-administered diet history questionnaire. Two thousand and six hundred two men and 1844 women aged more than 20 were analyzed. RESULTS: The mean age in men and women were 59.2 and 58.4 years old and the mean body mass index (BMI) were 23.7 and 22.3 kg/m2, respectively. The percentages of MetS were 20.6 in men and 6.1 in women. In some nutrients, significantly higher energy-adjusted intakes in subjects without MetS than with Mets appeared both in men and women after age adjustment. After adjusting by age, energy-adjusted intake beverages in men and cereals in women were significantly higher in subjects with MetS than those without MetS. The scores of all the categories in eating behavior were significantly worse in subjects with MetS than those without MetS. CONCLUSIONS: The differences in dietary intake between subjects with Mets and without Mets were relatively small. The scores of all the categories in eating behavior were worse in subjects with MetS than without MetS. It was suggested that the problem lay in the quality of diet, not in the quantity, caused by bad eating habits. The potential influence of eating behavior and nutritional intake on MetS was presented in men and women.

The Life Science Symposium held by the Nutrition Research Committee of the International Life Sciences Institute (ILSI) Japan in 2018, "Fusion of Nutrition and Exercise Sciences Leading to Extension of Healthy Life Expectancy," covered current topics in the science of nutrition and exercise to address extending healthy life expectancy. Presentation topics included (1) lifestyle and gut microbiota; (2) how to use lipids in sports nutrition; (3) the effect and molecular mechanism of improvement of arteriosclerosis by exercise and nutrition; (4) physical activity and nutrition that support brain function; (5) skeletal muscles and food ingredients that support healthy longevity; (6) measures against sarcopenia by exercise and nutrient intake; (7) physical activity/exercise for disease prevention; (8) nutritional epidemiology research for the Japanese population; (9) new developments in health science in viewed from nutrition and intestinal flora; (10) why do Asians develop nonobese metabolic disease?; and (11) social implementation of the health promotion program by ILSI Japan. The speakers emphasized the promotion of research on exercise and nutrition interactions and encouraged social implementation of the research results in public and private sectors.

CONTEXT: Lean body mass is essential for health, yet consensus regarding the effectiveness of protein interventions in increasing lean body mass is lacking. OBJECTIVE: The aim of this systematic review was to evaluate the dose-response relationship of the effects of protein intake on lean body mass. DATA SOURCES: The PubMed and Ichushi-Web databases were searched electronically, and reference lists of the literature included here and in other meta-analyses were searched manually. STUDY SELECTION: Randomized controlled trials evaluating the effects of protein intake on lean body mass were included. DATA EXTRACTION: Two authors independently screened the abstracts; 5 reviewed the full texts. RESULTS: A total of 5402 study participants from 105 articles were included. In the multivariate spline model, the mean increase in lean body mass associated with an increase in protein intake of 0.1 g/kg of body weight per day was 0.39 kg (95%CI, 0.36-0.41) and 0.12 kg (95%CI, 0.11-0.14) below and above the total protein intake of 1.3 g/kg/d, respectively. CONCLUSIONS: These findings suggest that slightly increasing current protein intake for several months by 0.1 g/kg/d in a dose-dependent manner over a range of doses from 0.5 to 3.5 g/kg/d may increase or maintain lean body mass. SYSTEMATIC REVIEW REGISTRATION: UMIN registration number UMIN000039285.

A high level of physical fitness, especially cardiorespiratory fitness, is associated with lower incidence of hypertension. However, the relationship between flexibility, which is a component of physical fitness, and the incidence of hypertension is unknown. The purpose of this study was to investigate the relationship between flexibility and the incidence of hypertension in a cohort study. A total of 22,972 (14,805 men and 8167 women; median age 49 years) normotensive participants were included in this study. Between April 2001 and March 2002, flexibility (standing forward bending) was measured using a standing trunk flexion meter. The participants were divided into quartiles of flexibility by sex and age group. Hypertension was defined as systolic blood pressure ≥ 140 mm Hg, diastolic blood pressure ≥ 90 mm Hg, or a self-reported history of previously diagnosed hypertension or current medication for hypertension at a health examination between April 2002 and March 2008. Hazard ratios and 95% confidence intervals (95% CI) for the incidence of hypertension were estimated using Cox proportional hazards models after adjusting for age, sex, body mass index, exercise habits, smoking status, and drinking status. During 102,948 person years of follow-up (median 5.6 years), 4235 participants developed hypertension. Compared with the lowest flexibility (quartile 1), hazard ratios and 95% CI were 0.96 (0.88 - 1.04) for quartile 2, 0.94 (0.86 - 1.03) for quartile 3, and 0.83 (0.76 - 0.91) for quartile 4. A high level of flexibility was associated with lower incidence of hypertension, independent of other confounding factors.

BACKGROUND: To examine the association between muscular and performance fitness (MPF) and the incidence of glaucoma. METHODS: A total of 27,051 glaucoma-free participants aged 20-87 years underwent physical fitness tests between April 2001 and March 2002. The MPF index was calculated using an age- and sex-specific summed z-score from grip strength, vertical jump, single-leg balance, forward bending, and whole-body reaction time. The participants were divided into quartiles according to the MPF index and each physical fitness test. Participants were followed up for the development of glaucoma, which was defined based on physician-diagnosed glaucoma at an annual health examination between April 2002 and March 2008. Hazard ratios for the incidence of glaucoma were estimated using Cox proportional hazards models. RESULTS: During follow-up, 303 participants developed glaucoma. Compared with the lowest MPF index group, hazard ratio (95% confidence interval) of developing glaucoma was 0.64 (0.46-0.89) for the highest MPF index group (P for trend = .001). Vertical jump and whole-body reaction time were associated with incident glaucoma (P for trend = .01 and <.001, respectively). There were no associations between the other physical fitness tests and the incidence of glaucoma. CONCLUSION: Higher MPF is associated with lower incidence of glaucoma.

AIM: To re-evaluate the suitability of calf circumference as a surrogate marker of low muscle mass measured by both bioelectrical impedance analysis (BIA) and dual-energy X-ray absorptiometry (DXA). We also examined the effects of obesity and age on low muscle mass screening using calf circumference. METHODS: In total, 1239 adults participated in this cross-sectional study. We measured the maximum calf circumference in a standing position and appendicular skeletal muscle mass (ASM) using BIA and DXA. We defined low muscle mass based on the Asian Working Group for Sarcopenia 2019 consensus. RESULTS: Calf circumference was positively correlated with BIA-measured ASM/height2 (men: r = 0.81, women: r = 0.73) and DXA-measured ASM/height2 (men: r = 0.78, women: r = 0.76). In the subgroup analyses by obesity and age, calf circumference was also positively correlated with ASM/height2 . The optimal calf circumference cut-offs for low muscle mass screening measured by BIA and DXA were 35 cm (sensitivity 91%, specificity 84%) and 36 cm (sensitivity 82%, specificity 80%) for men, and 33 cm (sensitivity 82%, specificity 84%) and 34 cm (sensitivity 85%, specificity 72%) for women, respectively. CONCLUSIONS: Calf circumference is positively correlated with BIA- and DXA-measured muscle mass regardless of obesity and age and is a simple and accurate surrogate marker of muscle mass for diagnosing sarcopenia. Geriatr Gerontol Int 2020; 20: 943-950.

The relative contribution of diet to colorectal cancer (CRC) incidence is higher than that for other cancers. Animal models have revealed that Escherichia coli containing polyketide synthase (pks+ E. coli) in the gut participates in CRC development. The purpose of this cross-sectional study was to examine the relationship between dietary intake and the prevalence of pks+ E. coli isolated from the microbiota in faecal samples of 223 healthy Japanese individuals. Dietary intake was assessed using a previously validated brief-type self-administered diet history questionnaire. The prevalence of pks+ E. coli was evaluated using faecal samples collected from participants and specific primers that detected pks+ E. coli. The prevalence of pks+ E. coli was 26.9%. After adjusting for baseline confounders, the prevalence of pks+ E. coli was negatively associated with the intake of green tea (odds ratio [OR], 0.59 [95% confidence interval (CI) 0.30-0.88] per 100 g/1,000 kcal increment) and manganese (OR, 0.43 [95% CI 0.22-0.85] per 1 mg/1,000 kcal increment) and was positively associated with male sex (OR, 2.27 [95% CI 1.05-4.91]). While futher studies are needed to validate these findings, these results provide insight into potential dietary interventions for the prevention of CRC.

Atrial fibrillation (AF) reduces the quality of life by triggering stroke and heart failure. The association between AF onset and gut metabolites suggests a causal relationship between AF and gut microbiota dysbiosis; however, the relationship remains poorly understood. We prospectively enrolled 34 hospitalized patients with AF and 66 age-, sex-, and comorbidity-matched control subjects without a history of AF. Gut microbial compositions were evaluated by amplicon sequencing targeting the 16S ribosomal RNA gene. We assessed differences in dietary habits by using a brief-type self-administered diet history questionnaire (BDHQ). Gut microbial richness was lower in AF patients, although the diversity of gut microbiota did not differ between the two groups. At the genus level, Enterobacter was depleted, while Parabacteroides, Lachnoclostridium, Streptococcus, and Alistipes were enriched in AF patients compared to control subjects. The BDHQ revealed that the intake of n-3 polyunsaturated fatty acids and eicosadienoic acid was higher in AF patients. Our results suggested that AF patients had altered gut microbial composition in connection with dietary habits.

BACKGROUND: Several cross-sectional studies have linked higher physical fitness with better hearing sensitivity but have not established a causal relation; none have used a prospective design that is less susceptible to bias. We used a prospective cohort study to investigate the association between muscular and performance fitness and the incidence of hearing loss. METHODS: A total of 21,907 participants without hearing loss received physical fitness assessments between April 2001 and March 2002. Muscular and performance fitness index, an age- and sex-specific summed z-score based on grip strength, vertical jump height, single-leg balance, forward bending, and whole-body reaction time was calculated. Participants were classified into quartiles according to the muscular and performance fitness index and each physical fitness test. They were followed up for the development of hearing loss, assessed by pure-tone audiometry at annual health examinations between April 2002 and March 2008. Hazard ratios and 95% confidence intervals for hearing loss incidence were estimated using Cox proportional hazards regression models. RESULTS: During follow-up, 2765 participants developed hearing loss. The hazard ratios (95% confidence intervals) for developing hearing loss across the muscular and performance fitness index quartiles (lowest to highest) were 1.00 (reference), 0.88 (0.79-0.97), 0.83 (0.75-0.93), and 0.79 (0.71-0.88) (Ptrend <.001). Among the various physical fitness components, a clear dose-response association with hearing loss incidence was observed for vertical jump height and single-leg balance (Ptrend <.001 for both). CONCLUSION: Higher muscular and performance fitness is associated with a lower incidence of hearing loss.

BACKGROUND: Grip strength reflects systemic muscle strength and mass and is reportedly associated with various metabolic variables. However, its prognostic association with dyslipidemia is unknown. We examined the association of grip strength and other physical fitness markers with the incidence of dyslipidemia among Japanese adults. METHODS: A total of 16,149 Japanese (6208 women) individuals aged 20-92 years who underwent a physical fitness test between April 2001 and March 2002 were included in this cohort study. Grip strength, vertical jump, single-leg balance with eyes closed, forward bending, and whole-body reaction time were evaluated at baseline. Dyslipidemia was annually determined based on fasting serum lipid profiles and self-reported dyslipidemia from April 2001 to March 2008. RESULTS: During the follow-up period, 4458 (44.9%) men and 2461 (39.6%) women developed dyslipidemia. A higher relative grip strength (grip strength/body mass index) was associated with a lower incidence of dyslipidemia among both men and women (P for trend < 0.001). Compared with those for the first septile, the hazards ratios and 95% confidence intervals for the seventh septile were 0.56 (0.50, 0.63) for men and 0.69 (0.58, 0.81) for women. Moreover, relative vertical jump (vertical jump strength/body mass index) was also inversely associated with the incidence of dyslipidemia among both men and women (P for trend < 0.001). There was no association between other physical fitness and dyslipidemia among both men and women. CONCLUSION: Relative grip strength and vertical jump may be useful risk markers of the incidence of dyslipidemia.

PURPOSE: Iron is an important component of the oxygen-binding proteins and may be critical to optimal athletic performance. Previous studies have suggested that the G allele of C/G rare variant (rs1799945), which causes H63D amino acid replacement, in the HFE is associated with elevated iron indexes and may give some advantage in endurance-oriented sports. The aim of the present study was to investigate the association between the HFE H63D polymorphism and elite endurance athlete status in Japanese and Russian populations, aerobic capacity and to perform a meta-analysis using current findings and three previous studies. METHODS: The study involved 315 international-level endurance athletes (255 Russian and 60 Japanese) and 809 healthy controls (405 Russian and 404 Japanese). Genotyping was performed using micro-array analysis or by PCR. VO2max in 46 male Russian endurance athletes was determined using gas analysis system. RESULTS: The frequency of the iron-increasing CG/GG genotypes was significantly higher in Russian (38.0 vs 24.9%; OR 1.85, P = 0.0003) and Japanese (13.3 vs 5.0%; OR 2.95, P = 0.011) endurance athletes compared to ethnically matched controls. The meta-analysis using five cohorts (two French, Japanese, Spanish, and Russian; 586 athletes and 1416 controls) showed significant prevalence of the CG/GG genotypes in endurance athletes compared to controls (OR 1.96, 95% CI 1.58-2.45; P = 1.7 × 10-9). Furthermore, the HFE G allele was associated with high V̇O2max in male athletes [CC: 61.8 (6.1), CG/GG: 66.3 (7.8) ml/min/kg; P = 0.036]. CONCLUSIONS: We have shown that the HFE H63D polymorphism is strongly associated with elite endurance athlete status, regardless ethnicities and aerobic capacity in Russian athletes.

Objectives: This study examined how healthcare costs might change by reducing long-term care needs among older Japanese people. Methods: A simulation model was constructed comprising two aging chains for independent and dependent people aged ≥65 years by sex. Changes in the base run from 2020 to 2040 were compared with those in two hypothetical scenarios: a 2% annual reduction in death rates (S1), and S1 plus a 2% annual reduction in the proportion of dependent people aged 65 years and in transition rates from the independent to dependent state for people aged ≥65 years (S2). Results: In the base run, the population increased by 13.0% for men and 11.3% for women, and the proportion of dependent people increased by 4.6% for men but decreased by 13.4% for women. The sum of medical and long-term care expenditure increased in the base run, S1, and S2 by 8.2, 27.4, and 16.4%, respectively, for men and women combined. Conclusions: Healthcare costs will increase as death rates fall, but the increase will be attenuated if the proportion of dependent people decreases.

With an ever-increasing interest in understanding the relationships between the microbiota and the host, more tools to map, analyze and interpret these relationships have been developed. Most of these tools, however, focus on taxonomic profiling and comparative analysis among groups, with very few analytical tools designed to correlate microbiota and the host phenotypic data. We have developed a software program for creating a web-based integrative database and analysis platform called MANTA (Microbiota And pheNoType correlation Analysis platform). In addition to storing the data, MANTA is equipped with an intuitive user interface that can be used to correlate the microbial composition with phenotypic parameters. Using a case study, we demonstrated that MANTA was able to quickly identify the significant correlations between microbial abundances and phenotypes that are supported by previous studies. Moreover, MANTA enabled the users to quick access locally stored data that can help interpret microbiota-phenotype relations. MANTA is available at https://mizuguchilab.org/manta/ for download and the source code can be found at https://github.com/chenyian-nibio/manta.

We determined the total energy expenditure (TEE) of healthy overweight or obese people, and those with impaired glucose tolerance and/or impaired fasting glycemia (IGT/IFG), or type 2 diabetes (T2DM) using the doubly-labeled water method. As a second purpose, we compared the measured TEE with the target energy intake recommended in the treatment guidelines for diabetes. The participants were normal glucose tolerance (NGT), and IGT/IFG (n=11) and T2DM (n=9) patients, who were 50-59 y and had a body mass index >25 kg/m2. The median TEE/body mass (BM) values were 32.6, 33.3, and 34.4 kcal/kg BM and the TEE/target BM values (target BM: BM at a BMI of 22 kg/m2) were 43.7, 50.2, and 46.5 kcal/kg target BM for each group, respectively, and did not differ significantly among them. Obese Japanese participants with T2DM in this study had lower TEE/BM than previously studied in non-obese participants with T2DM. In IGT/IFG or T2DM patients, if 30 kcal/kg target BM was used as the energy coefficient, on the basis of the treatment guidelines, the difference between TEE and the target energy intake would be -1,174±552 kcal (-38±11%). When 35 kcal/kg target BM was used as the energy coefficient, the difference between TEE and the target energy intake would be -877±542 kcal (-27±13%). Thus, the energy coefficients used to estimate target energy intake during lifestyle modification in obese/overweight patients with T2DM are considered to be quite low during the first step of diet therapy.

Background: The genetic predisposition to elite athletic performance has been a controversial subject due to the underpowered studies and the small effect size of identified genetic variants. The aims of this study were to investigate the association of common single-nucleotide polymorphisms (SNPs) with endurance athlete status in a large cohort of elite European athletes using GWAS approach, followed by replication studies in Russian and Japanese elite athletes and functional validation using metabolomics analysis. Results: The association of 476,728 SNPs of Illumina DrugCore Gene chip and endurance athlete status was investigated in 796 European international-level athletes (645 males, 151 females) by comparing allelic frequencies between athletes specialized in sports with high (n = 662) and low/moderate (n = 134) aerobic component. Replication of results was performed by comparing the frequencies of the most significant SNPs between 242 and 168 elite Russian high and low/moderate aerobic athletes, respectively, and between 60 elite Japanese endurance athletes and 406 controls. A meta-analysis has identified rs1052373 (GG homozygotes) in Myosin Binding Protein (MYBPC3; implicated in cardiac hypertrophic myopathy) gene to be associated with endurance athlete status (P = 1.43 × 10-8, odd ratio 2.2). Homozygotes carriers of rs1052373 G allele in Russian athletes had significantly greater VO2
max
than carriers of the AA + AG (P = 0.005). Subsequent metabolomics analysis revealed several amino acids and lipids associated with rs1052373 G allele (1.82 × 10-05) including the testosterone precursor androstenediol (3beta,17beta) disulfate. Conclusions: This is the first report of genome-wide significant SNP and related metabolites associated with elite athlete status. Further investigations of the functional relevance of the identified SNPs and metabolites in relation to enhanced athletic performance are warranted.

目的:全国の都道府県を対象として,身体活動促進を目的とした行動計画の策定とその実施状況を明らかにすること。方法:Bullらが開発した「健康増進のための身体活動に関する国の政策を監査するためのツール(Health-Enhancing Physical Activity Policy Audit Tool;HEPA PAT)」を改変し,地方自治体向けの新たな政策監査ツール(Local PAT;L-PAT)を作成した。内容は,「身体活動促進に関する行動計画の策定」,「行動計画の策定における部門・組織間の連携」,「実際に行われた事業や活動」など11項目とした。研究期間は2015年8月から2016年3月であった。対象は全国47都道府県の保健,スポーツ,教育,都市計画,交通,環境の6つの部門で,合計282(47都道府県×6部門)であった。結果:全対象282のうち202から回答が得られ,回答率は71.6%であった。保健部門とスポーツ部門は,行動計画の策定率(それぞれ100%,97.6%)および実施率(それぞれ93.6%,100%)が他の部門よりも高かった。環境整備に携わる都市計画部門と交通部門においても行動計画が策定されていたが(それぞれ55%,30%),実施率は低かった(それぞれ13.6%,22.2%)。保健,スポーツ,教育の部門間には連携が認められたが,その他の部門との連携は不十分だった。結論:都道府県レベルの身体活動促進に関する行動計画の策定・実施は,保健部門とスポーツ部門を中心に行われていた。都市計画部門や交通部門においても関連する計画がみられた。今後は策定や実施の具体的内容および活動の効果など質的な検討が求められる。(著者抄録)

BACKGROUND: Self-monitoring using certain types of pedometers and accelerometers has been reported to be effective for promoting and maintaining physical activity (PA). However, the validity of estimating the level of PA or PA energy expenditure (PAEE) for general consumers using wearable devices has not been sufficiently established. OBJECTIVE: We examined the validity of 12 wearable devices for determining PAEE during 1 standardized day in a metabolic chamber and 15 free-living days using the doubly labeled water (DLW) method. METHODS: A total of 19 healthy adults aged 21 to 50 years (9 men and 10 women) participated in this study. They followed a standardized PA protocol in a metabolic chamber for an entire day while simultaneously wearing 12 wearable devices: 5 devices on the waist, 5 on the wrist, and 2 placed in the pocket. In addition, they spent their daily lives wearing 12 wearable devices under free-living conditions while being subjected to the DLW method for 15 days. The PAEE criterion was calculated by subtracting the basal metabolic rate measured by the metabolic chamber and 0.1×total energy expenditure (TEE) from TEE. The TEE was obtained by the metabolic chamber and DLW methods. The PAEE values of wearable devices were also extracted or calculated from each mobile phone app or website. The Dunnett test and Pearson and Spearman correlation coefficients were used to examine the variables estimated by wearable devices. RESULTS: On the standardized day, the PAEE estimated using the metabolic chamber (PAEEcha) was 528.8±149.4 kcal/day. The PAEEs of all devices except the TANITA AM-160 (513.8±135.0 kcal/day; P>.05), SUZUKEN Lifecorder EX (519.3±89.3 kcal/day; P>.05), and Panasonic Actimarker (545.9±141.7 kcal/day; P>.05) were significantly different from the PAEEcha. None of the devices was correlated with PAEEcha according to both Pearson (r=-.13 to .37) and Spearman (ρ=-.25 to .46) correlation tests. During the 15 free-living days, the PAEE estimated by DLW (PAEEdlw) was 728.0±162.7 kcal/day. PAEE values of all devices except the Omron Active style Pro (716.2±159.0 kcal/day; P>.05) and Omron CaloriScan (707.5±172.7 kcal/day; P>.05) were significantly underestimated. Only 2 devices, the Omron Active style Pro (r=.46; P=.045) and Panasonic Actimarker (r=.48; P=.04), had significant positive correlations with PAEEdlw according to Pearson tests. In addition, 3 devices, the TANITA AM-160 (ρ=.50; P=.03), Omron CaloriScan (ρ=.48; P=.04), and Omron Active style Pro (ρ=.48; P=.04), could be ranked in PAEEdlw. CONCLUSIONS: Most wearable devices do not provide comparable PAEE estimates when using gold standard methods during 1 standardized day or 15 free-living days. Continuous development and evaluations of these wearable devices are needed for better estimations of PAEE.

AIMS/INTRODUCTION: To investigate the relationship between combined aerobic and resistance training, and the incidence of type 2 diabetes mellitus. MATERIALS AND METHODS: The present study included 10,680 Japanese women. Participants enrolled between 2005 and 2010, and were followed up until 2014. The frequency of combined training was counted for the first 3 months, the 6th month and the 9th month. In 2014, women reported whether or not they had diabetes, as well as the year of developing diabetes. Hazard ratios and 95% confidence intervals (CI) for the incidence of type 2 diabetes were obtained using Cox proportional hazard models. RESULTS: The median duration of follow up was 5 years, with 166 women developing type 2 diabetes. Using the lowest frequency of training group (1st quartile) as the reference, the hazard ratios for the second through fourth quartiles was as follows: 0.95 (95% CI 0.64-1.41), 0.73 (95% CI 0.48-1.13) and 0.69 (95% CI 0.44-1.07), respectively (P for trend = 0.116). After adjustment for age, body mass index and thigh circumference, the hazard ratios were: 0.84 (95% CI 0.56-1.26), 0.69 (95% CI 0.45-1.06) and 0.61 (95% CI 0.39-0.95), respectively (P for trend = 0.040). CONCLUSIONS: A higher frequency of combined aerobic and resistance training is associated with a lower risk of developing type 2 diabetes in Japanese women.

BACKGROUND: Simple physical fitness test can be a useful potential predictor of type 2 diabetes (T2DM). We examined the association between performances on simple physical fitness tests and the incidence of T2DM. METHODS: This longitudinal study was conducted in 21,802 nondiabetic Japanese (6,649 women) aged 20 to 92 years, who underwent all physical fitness tests at baseline (April 2001 to March 2002). From April 2001 to March 2008, physical fitness tests, including grip strength, vertical jump, single-leg balance with eyes closed, forward bending, whole-body reaction time, and supine legs-up, were performed every year. Participants had physical fitness tests at least two times during the period. T2DM was also annually determined based on fasting blood glucose, glycated hemoglobin, and self-reported diabetes during the period. Discrete-time logit models were used to examine the influence of the serial level of each physical fitness test on the incidence of T2DM. RESULTS: During the entire study period, 972 participants developed diabetes. Lower relative grip strength (grip strength/body weight) and single-leg balance performance were associated with a higher incidence of T2DM. For relative grip strength, as compared with the fourth quartile group, the odds ratios for other groups ranged from 1.16 to 1.56 (P for trend < 0.001). For single-leg balance, the odds ratios ranged from 1.03 to 1.49 (P for trend < 0.001). CONCLUSION: The performance of a simple single-leg balance test as well as that of a grip strength test were negatively associated with the risk of T2DM among Japanese.

運動に関する感情経験、態度、行動意図を評価する尺度を作成し、その妥当性・信頼性を検証するとともに、感情要因と運動行動との相互関連性について検討した。60歳代であり、かつ配偶者と同居している500名を対象に、質問紙によるインターネット調査を行った。運動の感情経験尺度を探索的因子分析した結果、2因子が抽出され、各因子には因子負荷量の大きい上位3項目が採用された。運動への態度尺度、運動の行動意図尺度の探索的因子分析でも2因子が抽出された。運動行動と肯定的な感情経験尺度、感情的態度尺度、手段的態度尺度および運動の継続意図尺度との効果量は大きく、運動行動と阻害要因への対処意図尺度との関連性の効果量は中程度であった。1年後の追跡調査時にも、初期モデルと同様に感情的態度が運動行動の予測因子であった。感情的態度には、肯定的および否定的な感情経験が直接関連していた。

OBJECTIVES: Although maintaining cardiorespiratory fitness is encouraged to reduce the risk of hypertension, the level at, and length of time for which, individuals need to maintain fitness remains unclear. We examined the association between the frequency of achieving the recommended fitness levels of the 'Physical Activity Reference for Health Promotion 2013' and the risk of hypertension among Japanese men. METHODS: This cohort study was conducted in 6653 men without hypertension enrolled in 1986. Whether the participants' fitness level was equal to or exceeded the reference value (fit) or not (unfit) was determined. The frequency of achieving the recommended fitness level was calculated by counting the number of times the fitness level was achieved in 1980 through 1986. Incident hypertension was defined as the first visit with a SBP/DBP of at least 140/90 mmHg or self-reported antihypertensive medication use and was evaluated during annual health examinations from 1986 until 2009. RESULTS: During the follow-up period, 3630 men developed hypertension. The multivariable-adjusted hazard ratios (95% confidence interval) for incident hypertension comparing men with fit versus unfit at baseline was 0.79 (0.74-0.85). Moreover, the frequency of achieving the recommended fitness level was inversely associated with the incidence of hypertension. The risk of hypertension was lower among those who achieved three or more of the recommended levels (0.72 for three times to 0.62 for seven times). CONCLUSION: Achieving the fitness level recommended in the Japanese guideline three or more times during a 6-year period can be beneficial for the risk reduction of hypertension.

Faecal volume, form, colour, and odour are associated with various diseases, dietary habits, and the gut microbiome. Multifaceted assessment of faecal condition will be needed for future research and practice. Faecal observation has advantages, as it is non-invasive, frequent, and easy. We have developed and validated an illustrative card tool for comprehensively faecal assessment. In 38 healthy adults, observations of volume, form, colour, and odour of faeces using the tool were compared to the objective characteristics of the actual faeces determined using a weighing scale, moisture meter, hardness meter, colourimeter, and odour measuring device. A significant positive correlation (ρ = 0.778) was observed between the number of faecal model (2 cm × 10 cm) units and the actual weight. The Bristol Stool Form Scale showed a significant positive correlation with the moisture content (ρ = 0.717) and negative correlations with faecal hardness (ρ = -0.843) and adhesiveness (ρ = -0.761). The L*a*b* colour space values of the stool differed significantly among observational judgments using the colour card tool. No significant correlation was observed between the observation of odour and the measured odour index. In conclusion, the faecal volume, form, and colour can be estimated by observation using the multifaceted assessment card tool.

© 2019 Japanese Society of Physical Fitness and Sports Medicine. All rights reserved. This study aimed to develop affective experience, attitude, and behavioral intention scales for exercise, and examine their associations with exercise behavior. A web-based questionnaire survey was conducted among 500 individuals aged 60 to 69 years at baseline. The survey measured respondents’ affective experiences, attitude, behavioral intention, exercise behavior, and demographic factors. The same survey was conducted 2 weeks (n = 345) and 1 year later (n = 338). Exploratory and confirmatory factor analyses showed that the factor structures of the affective experience (2 factors: 3 items each for positive experience and negative experience), attitude (2 factors: 3 items each for affective attitudes and instrumental attitudes), and behavioral intention scales (2 factors: 4 items each for intention to maintain behavior and intention to overcome barriers) were acceptable. For these scales, the Cronbach’s alpha coefficients ranged from 0.69 to 0.92, Pearson’s correlation coefficients for baseline and 2-week follow-up ranged from 0.51 to 0.81, and Cohen’s d values for the associations with exercise behavior ranged from 0.46 to 0.98. After adjusting for demographic factors and exercise behavior at baseline, structural equation modeling showed that an affective attitude toward exercise at baseline significantly predicted exercise behavior at 1-year follow-up (standardized coefficient = 0.27), and that the affective attitude was predominantly explained by the positive affective experience of exercise (standardized coefficient = 0.80). The results confirmed the validities and reliabilities of the scales. Positive affective experiences and affective attitudes may be important determinants of exercise behavior.

BACKGROUND AND OBJECTIVES: Limited information is available on how weight loss intervention programs affect skeletal muscle mass especially in trunk. METHODS AND STUDY DESIGN: A total of 235 overweight Japanese men and women aged 40-64 years with a body mass index of 28.0 to 44.8 kg/m2 participated in this randomized controlled intervention study. They were randomly divided into a lifestyle intervention group and control group. Before and after the one-year lifestyle intervention for weight loss an abdominal transverse image was acquired by computed tomography. The cross-sectional areas (CSAs) of visceral fat, subcutaneous fat, and skeletal muscle of rectus abdominis, abdominal oblique, iliopsoas, and erector spinae muscle were calculated. RESULTS: The body weight changed by approximately -5% in the intervention groups. The corresponding values for subcutaneous fat and visceral fat CSAs were -10.8 to -17.5% in both sexes. The reductions observed in skeletal muscle CSAs were significantly less (-6.0% and -7.2% in the men and women intervention groups respectively) than those in fat tissue CSAs. The CSA of each of the four skeletal muscle groups also significantly decreased; however, after adjustments for body weight at each time point, only reductions in the iliopsoas muscle in both sex and abdominal oblique muscles in men remained significant. CONCLUSIONS: The lifestyle weight loss intervention might reduce the relative amount of the abdominal skeletal muscles especially in iliopsoas muscle.

Background: The momentum to promote physical activity (PA) by various government agencies such as the Japan Sports Agency established in 2015, academic organizations, and companies is increasing towards the Tokyo Olympic and Paralympic Games. The goal of the 2018 Japan Report Card on Physical Activity for Children and Youth is to assess and track levels of health behaviors related to PA in Japanese children and youth, facilitators and barriers for PA, and related health outcomes. Methods: Nationally representative data were used to score the indicators. Results: The 2018 Japan Report Card on Physical Activity for Children and Youth consists of health behaviors and outcomes (7 indicators), and influences on health behaviors (4 indicators). The key four health behaviors and outcomes (Organized Sport Participation: B-; Active Transportation: A-; Physical fitness: A, Weight status: A) were favorable. Sedentary Behavior received C- grade, while 2 indicators (Overall Physical Activity, and Active Play) could not be graded. In the Influences domain, Family Influence and Community were graded as C-, while School (B+), Community and Environment (B-), and Government Strategies and Investments (B) were favorable. Conclusions: The 2018 Japan Report Card on Physical Activity for Children and Youth shows that Japanese children and youth have favorable levels of organized sport participation, active transportation to and from school, and physical fitness and weight status. Future nationally representative surveys on overall PA and active play are needed.

AIM: Recent studies have suggested that non-high-density lipoprotein cholesterol (non-HDL-C) may be a good marker of coronary heart disease and cardiovascular disease risk. Therefore, we investigated the relationship between cardiorespiratory fitness (CRF) and non-HDL-C. METHODS: We evaluated CRF and the incidence of high level of non-HDL-C in 4,067 Japanese men without dyslipidemia. The participants were given a submaximal exercise test, a medical examination, and questionnaires on their health habits in 1986. A cycle ergometer was used to measure the CRF and maximal oxygen uptake was estimated. The incidence of a high level of non-HDL -C (≥170 mg/dL) from 1986 to 2006 was ascertained based on the fasting blood levels. A high level of non-HDL-C was found in 1,482 participants during the follow-up. Cox proportional hazard models were used to obtain the hazard ratios (HRs) and 95% confidence intervals (CIs) for the incidence of a high level of non-HDL-C. RESULTS: Following age adjustment, and using the lowest CRF group (quartile Ⅰ) as reference, the HRs and 95% CIs for quartiles II through IV were: 1.00 (95% CI: 0.87-1.15), 0.87 (95% CI: 0.76-1.00), and 0.70 (95% CI: 0.60-0.81), respectively (P for trend ＜0.001). After additional adjustment for body mass index, systolic blood pressure, smoking, alcohol intake, and family history of dyslipidemia, the HRs and 95% CIs were: 1.05 (95% CI: 0.92-1.21), 0.94 (95% CI: 0.81-1.08), and 0.79 (95% CI: 0.67-0.92), respectively (P for trend=0.001). CONCLUSIONS: These results suggest that there is an inverse relationship between CRF levels and the incidence of a high level of non-HDL-C in Japanese men.

Family history of hypertension (FH) is a nonmodifiable risk factor for hypertension. However, cardiorespiratory fitness (CRF) is a modifiable risk factor and might be important for preventing hypertension in both people with and without FH. The purpose of this study was to investigate the combined association of CRF and FH on the incidence of hypertension in normotensive male Japanese workers. A total of 6890 workers were included in this study. CRF was determined using a submaximal exercise test. A self-reported questionnaire was used to determine FH. Six groups were established, combining the two groups with and without FH (Yes, No) and the three CRF groups (Low, Moderate, High). The incidence of hypertension, defined as systolic blood pressure of ≥140 mmHg or diastolic blood pressure of ≥90 mmHg, or self-reported physician-diagnosed hypertension was evaluated. During the observation period of 101,212 man-years (median 17 years, minimum 1 year, maximum 23 years), 2210 workers developed hypertension. There were 3860 participants who had FH (56%). Compared with the Yes-Low CRF group, the HRs (95% CI) for hypertension were 66% lower in the No-High CRF group (0.34 [0.28-0.40]), 47% lower in the No-Low CRF group (0.53 [0.46-0.61]), and 24% lower in the Yes-High CRF group (0.76 [0.67-0.86]). FH and CRF did not show a significant interaction (p for interaction = 0.181). The combination of FH and CRF showed a clear association with the risk of incident hypertension, and moderate to high levels of CRF might be equally beneficial for preventing hypertension for both people with and without FH.

Type 2 diabetes is increasing globally and in Asia. The purpose of this study was to examine the association of a fit-fat index (FFI) with diabetes incidence among, Japanese men. In total 5,014 men aged 18-64 years old, who had an annual health check up with no history of major chronic disease at baseline from 2002 to 2009 were observed. CRF was estimated via cycle ergometry. Overall, 7.6% of the men developed diabetes. The mean follow-up period was 5.3 years. Hazard ratios, 95% confidence intervals and P trend for diabetes incidence were obtained using the Cox proportional hazards model while adjusting for confounding variables. High FFI demonstrated lower risk 0.54 (0.36-0.82) compared to low BMI 0.63 (0.44-0.90), low WHtR 0.64 (0.41-1.02), and High CRF 0.72 (0.51-1.03). FFI showed a marginally stronger dose response relationship across quartiles (P (trend) =0.001) compared to BMI (P (trend) =0.002), WHtR (P (trend) =0.055), and CRF (P (trend) =0.005). Overall, both fitness and fatness play independent roles in determining diabetes incidence in, Japanese men. FFI may be a more advantageous physical fitness measure because it can account for changes in fitness and/or fatness.

© 2018 Human Kinetics, Inc. Caffeine has been described as a sports performance-enhancing substance. However, it is unclear whether it can increase the level of physical activity (PA) in nonathletic individuals. This study investigates the relationship between daily caffeine consumption and (a) daily PA/fitness or (b) intervention-induced changes in PA in women and men. On the basis of responses to a dietary habit questionnaire, which included items on caffeinated beverages, 1,032 Japanese adults, were categorized into lower or higher caffeine consumption groups (relative to the median caffeine consumption). In each group, daily step count; sedentary time; and light, moderate, and vigorous PA outcomes were objectively measured. Physical fitness, including peak oxygen consumption, was also evaluated. The relationship between daily caffeine consumption and the change in the levels of PA was investigated in a subgroup of 202 subjects who participated in a 1-year PA counseling intervention. Women in the higher caffeine consumption group presented higher moderate-to-vigorous PA and step count compared with their counterparts in the lower consumption group (4.0 ± 2.1 vs. 3.3 ± 2.1 MET-hr/day, p &lt; .001; 10,335 ± 3,499 vs. 9,375 ± 3,527 steps/day, p &lt; .001). A significant positive correlation was noted between caffeine consumption and peak oxygen consumption among women (r = .15, p &lt; .001). No caffeine-related effects were noted in men. The lower and higher caffeine consumption groups showed no significant differences in their levels of PA at the end of the 1-year intervention. Therefore, caffeine consumption appears to be associated with higher levels of PA in Japanese women. Further studies are needed to clarify this association.

In Japan, health insurers are obliged to conduct Specific Health Checkup (SHC) for middle-aged and elderly persons. High-risk persons are referred to Specific Health Guidance (SHG) to receive behavioral counseling based on individual action plans including targets for modification of daily energy balance through diet and physical activity. Using individual-level observational data, we examined the effects of diet and physical activity counseling on cardiometabolic biomarkers across the country. Subjects were 363,440 high-risk persons aged 40-64 who participated in intensive support in SHG for ≥3 months between April 2008 and March 2012. We considered participants as receiving counseling on diet alone, physical activity alone, combined, or neither if they had targets for diet only, physical activity only, both, or neither, respectively. Biomarkers included body mass index, waist circumference, systolic and diastolic blood pressure, high-density lipoprotein cholesterol, and hemoglobin A1c. Under the difference-in-differences approach, we used multivariable linear regression on repeated measures of biomarkers at SHCs before and after SHG and estimated the effects of each counseling type as an interaction with time of SHC. Compared with neither counseling, diet and physical activity counseling, alone or combined, were significantly associated with additional improvements in biomarkers after SHG, for example, body mass index (men: 0.03-0.06 kg/m2, women: 0.10-0.15 kg/m2) and waist circumference (men: 0.16-0.29 cm, women: 0.43-0.47 cm) in both sexes and high-density lipoprotein cholesterol in men (0.13-0.29 mg/dL). Modest improvements in biomarkers were associated with diet and physical activity counseling, although effect sizes were small.

© 2016 Asia Oceania Association for the Study of Obesity Background: Quantitative evaluation of visceral fat mass and skeletal muscle mass is important for health promotion. Recently, some studies suggested the existence of adipocyte–myocyte negative crosstalk. If so, abdominal skeletal muscles may easily and negatively affected not only by the age but also the visceral fat because age-related reduction in abdominal region is greater compared with limbs. Objective: We cross-sectionally examined the existence of quantitative associations between visceral fat area and abdominal skeletal muscle distribution in overweight people. Methods: A total of 230 Japanese males and females who aged 40–64 years and whose body mass index (BMI) was 28.0–44.8 kg/m 2 participated in this study. The cross-sectional area (CSA) of the visceral fat, subcutaneous fat, and abdominal skeletal muscles, namely, the rectus abdominis, abdominal oblique, erector spinae, and iliopsoas muscles were measured by the computed tomography images. Results: Stepwise regression analyses revealed the existence of sex difference in the relation between visceral fat CSA and other morphological variables. In males, BMI was a positive, and the iliopsoas muscle group CSA was a negative contributor of the visceral fat CSA. In females, both age and BMI were selected as positive contributors. Conclusion: These data suggested that the visceral fat CSA may negatively associated with iliopsoas muscle group CSA in males. In females, the visceral fat CSA was not significantly related to the distribution of the abdominal skeletal muscle groups.

We aimed to replicate, in a specific athletic event cohort (only track and field) and in two different ethnicities (Japanese and East European, i.e. Russian and Polish), original findings showing the association of the angiotensin-II receptor type-2 gene (AGTR2) rs11091046 A>C polymorphism with athlete status. We compared genotypic frequencies of the AGTR2 rs11091046 polymorphism among 282 track and field sprint/power athletes (200 men and 82 women), including several national record holders and Olympic medallists (214 Japanese, 68 Russian and Polish), and 2024 control subjects (842 men and 1182 women) (804 Japanese, 1220 Russian and Polish). In men, a meta-analysis from the two combined cohorts showed a significantly higher frequency of the C allele in athletes than in controls (odds ratio: 1.62, P=0.008, heterogeneity index I
2
=0%). With regard to respective cohorts, C allele frequency was higher in Japanese male athletes than in controls (67.7% vs. 55.9%, P=0.022), but not in Russian/Polish male athletes (61.9% vs. 51.0%, P=0.172). In women, no significant results were obtained by meta-analysis for the two cohorts combination (P=0.850). The AC genotype frequency was significantly higher in Russian/Polish women athletes than in controls (69.2% vs. 42.1%, P=0.022), but not in Japanese women athletes (P=0.226). Our results, in contrast to previous findings, suggested by meta-analysis that the C allele of the AGTR2 rs11091046 polymorphism is associated with sprint/power track and field athlete status in men, but not in women.

Background: There are several studies on the relationship between low back pain and physical activity. However, the results of these studies vary, and the relationship between them remains unclear. Therefore, we conducted a cross-sectional study to evaluate the association between objectively measured physical activity and low back pain in Japanese men. Methods: The study included 4022 Japanese men [average age: 47 (10) y]. Daily amount of moderate to vigorous physical activity and step counts were measured using an accelerometer. Low back pain, drinking and smoking, and lifestyle-related diseases were surveyed using a self-administered questionnaire. A logistic regression model was used to evaluate the relationship between physical activity and step counts with persistent low back pain after adjusting for confounders. Results: Persistent low back pain was reported in 428 participants. The multivariable-adjusted odds ratios of presenting persistent low back pain across quartiles of amount of moderate to vigorous physical activity were 1.00 (reference)
0.93 (95% confidence interval, 0.70-1.22)
0.97 (95% confidence interval, 0.74-1.28)
and 0.67 (95% confidence interval, 0.50-0.90)
P for linearity =.012. Conclusion: We found a significant inverse relationship between objectively measured physical activity and persistent low back pain.

© 2017 Ryoko Kawakami et al. Background: We sought to examine the association between cardiorespiratory fitness (CRF) and incidence of type 2 diabetes considering the follow-up period in a cohort of Japanese men with a maximum follow-up period of 23 years. Methods: This study enrolled 7,804 male workers free of diabetes in 1986. CRF was measured using a cycle ergometer, and maximal oxygen uptake was estimated. During 1986–2009, participants were followed for development of type 2 diabetes, which was diagnosed using fasting blood tests, self-administered questionnaires, or oral glucose tolerance tests after urinary tests from annual health checkups. Hazard ratios for the incidence of type 2 diabetes were estimated using Cox proportional hazards models. Results: During the follow-up period, 1,047 men developed type 2 diabetes. In analyses by follow-up periods (1986–1993, 1994–2001, and 2002–2009), there was an inverse dose-response relationship between CRF and the development of type 2 diabetes for all three follow-up periods (P for trend 0.019, &lt;0.001, and 0.001, respectively), and the association between CRF at baseline and the incidence of type 2 diabetes did not weaken with longer follow-up period. Compared with the lowest CRF group, hazard ratios of developing type 2 diabetes were 0.69 (95% confidence interval [CI], 0.49–0.97) for the highest CRF group in 1986–1993, 0.57 (95% CI, 0.42–0.79) for the highest CRF in 1994–2001, and 0.47 (95% CI, 0.30–0.74) for the highest CRF in 2002–2009. Conclusion: High CRF is associated with a lower risk of the incidence of type 2 diabetes over an extended period of &gt;20 years among men.

© 2017 Haruki Momma et al. Background: The “Physical Activity Reference for Health Promotion 2013” provides “fit” reference values for cardiorespiratory fitness (CRF) for good health. The importance of achieving a fit CRF level for several years on the subsequent prevention of type 2 diabetes mellitus (T2DM) remains to be clarified. Methods: This cohort study was conducted in 2,235 nondiabetic males aged 21 to 59 years, enrolled in April 1986 through March 1987. We calculated the ratio of the area under the curve (AUCratio) for actual measured values and the AUC for the reference values of CRF in each individual during an 8-year measurement period before the baseline. According to whether they met a fit CRF level or not, participants were categorized into groups based on the AUCratio (FitAUC or UnfitAUC) and initial CRF (Fitinitial or Unfitinitial), respectively. T2DM was evaluated on health checkups until March 2010. Results: During the follow-up period, 400 men developed T2DM. After adjustment for confounders, as compared with those in the FitAUC group, the hazard ratio (HR) for those in the UnfitAUC group was 1.33 (95% confidence interval [CI], 1.06–1.65). A combined analysis with the categories of initial value and AUCratio showed that, compared with the Fitinitial and FitAUC group, the HRs of Fitinitial and UnfitAUC, Unfitinitial and FitAUC, and Unfitinitial and UnfitAUC groups were 1.41 (95% CI, 0.99–2.00), 1.18 (95% CI, 0.81–1.70), and 1.40 (95% CI, 1.08–1.83), respectively. Conclusion: Achievement of a fit CRF level established in the Japan physical activity guideline for several years was associated with lower subsequent risk of T2DM.

© The Author 2017. Background: Evidence from a limited number of short-term trials indicates the difficulty in achieving population-level improvements in physical activity (PA) through communitywide interventions (CWIs). We sought to evaluate the effectiveness of a 5-year CWI for promoting PA in middle-aged and older adults using a cluster randomized design. Methods: We randomized 12 communities in Unnan, Japan, to either intervention (9) or control (3). Additionally, intervention communities were randomly allocated to three subgroups by different PA types promoted. Randomly sampled residents aged 40-79 years responded to the baseline survey (n=4414; 74%) and were followed at 1, 3 and 5 years (78-83% response rate). The intervention was a 5-year CWI using social marketing to promote PA. The primary outcome was a change in recommended levels of PA. Results: Compared with control communities, adults achieving recommended levels of PA increased in intervention communities [adjusted change difference=4.6 percentage points (95% confidence interval: 0.4, 8.8)]. The intervention was effective for promoting all types of recommended PAs, i.e. aerobic (walking, 6.4%), flexibility (6.1%) and muscle-strengthening activities (5.7%). However, a bundled approach, which attempted to promote all forms of PAs above simultaneously, was not effective (1.3-3.4%, P≥0.138). Linear dose-response relationships between the CWI awareness and changes in PA were observed (P≤0.02). Pain intensity decreased in shoulder (intervention and control) and lower back (intervention only) but there was little change difference in all musculoskeletal pain outcomes between the groups. Conclusions: The 5-year CWI using the focused social marketing strategy increased the population-level of PA.

「健康と生活に関するアンケート」に回答した高齢者534名(男性260名、女性274名、68〜78歳)を対象とした。男女の比較で有意差を認めた人口統計学的属性・社会経済的属性は、居住形態(女性の独居割合が高い)、BMI(男性が高い)、身体活動の制限(女性の医師または足腰の痛みによる制限がある割合が高い)、教育歴(男性の大学卒以上の割合が高い)、収入がある仕事(男性の仕事をもつ割合が高い)であった。ソーシャル・キャピタル(SC)では地域の人とのかかわりと他世代との交流において有意な男女差(女性のSCが高い)を認めた。SCが低いと想定される回答を基準とした解析で、男性では、地域の支え合い:支え合うと思う、地域の人とのかかわり:立ち話をする人がいる、相談しあえる人がいる、他世代との交流:まあまあある、とてもあるにおいて有意な正の関連を認めた。トレンド検定では、有意な量反応関係を認めた。女性では、地域の人とのかかわり:相談しあえる人がいる、地域組織活動へ

Background: The relationship between the combination of physical activity (PA) and body mass index (BMI) with low back pain (LBP) is unclear. The present study offers a cross-sectional assessment of how combinations of PA and BMI are related to LBP in Japanese men. Methods: Participants were 4022 Japanese men (mean age = 47) who underwent regular clinical examinations. PA was measured using a uniaxial accelerometer and divided into tertiles (PAhigh, PAmiddle, PAlow). A self-administered questionnaire was used to report on persistent LBP experience, drinking and smoking habits, and any existing lifestyle diseases. After covariance adjustment, a logistic regression model was used to assess how combinations of PA and BMI are related to persistent LBP. Results: 428 of the participants had persistent LBP. A clear negative dose-response relationship was found between PA levels and persistent LBP (P for linearity = 0.012). Regarding BMI, odd ratios were shown to be higher in the overweight/obese category (BMI ≥ 25 kg/m2) than for the normal weight category (BMI &lt
25 kg/m2). When the PAhigh was taken as the reference in the normal weight category, odds ratios for PAlow and PAmiddle in the normal weight category were shown to be high. Moreover, in the overweight/obese category, odd ratios for every fitness level were also high as for the normal weight category. Conclusion: The present study showed that both PA and BMI are related to persistent LBP. Also, the prevalence of persistent LBP became higher when PAlow and high BMI are combined rather than the group of PAhigh and low BMI combination.

© 2017 John Wiley &amp; Sons A/S. Published by John Wiley &amp; Sons Ltd The aim of this study was to clarify heritability estimates for endurance-related phenotypes and the underlying factors affecting these estimates. A systematic literature search was conducted for studies reporting heritability estimates of endurance-related phenotypes using the PubMed database (up to 30 September 2016). Studies that estimated the heritability of maximal oxygen uptake (VO2max.), submaximal endurance phenotypes, and endurance performance were selected. The weighted mean heritability for endurance-related phenotypes was calculated using a random-effects model. A total of 15 studies were selected via a systematic review. Meta-analysis revealed that the weighted means of the heritability of VO2max absolute values and those adjusted for body weight and for fat-free mass were 0.68 (95% CI: 0.59-0.77), 0.56 (95% CI: 0.47-0.65), and 0.44 (95% CI: 0.13-0.75), respectively. There was a significant difference in the weighted means of the heritability of VO2max across these different adjustment methods (P &lt;.05). Moreover, there was evidence of statistical heterogeneity in the heritability estimates among studies. Meta-regression analysis revealed that sex could partially explain the heterogeneity in the VO2max heritability estimates adjusted by body weight. For submaximal endurance phenotypes and endurance performance, the weighted mean heritabilities were 0.49 (95% CI: 0.33-0.65) and 0.53 (95% CI: 0.27-0.78), respectively. There was statistically significant heterogeneity in the heritability estimates reported among the studies, and we could not identify the specific factors explaining the heterogeneity. Although existing studies indicate that genetic factors account for 44%-68% of the variability in endurance-related phenotypes, further studies are necessary to clarify these values.

目的:子どもにおける身体活動の評価法に関して、どのような質問紙が国際的に多く用いられているかを把握することは、今後、当該研究分野における国際比較研究を行っていくうえで極めて有益な情報となり得る。本研究は、子ども・青少年における質問紙を用いた身体活動の評価法に関する世界的な動向を整理することを目的とした。方法:子ども・青少年の身体活動に関する国際比較を行った"The Report Card on Physical Activity for Children and Youth(Report Card)"に参加した38か国を対象とした。各国のReport Cardにおいて、日常生活全般の身体活動量の等級付けの根拠となっている文献を収集することにより、各国における身体活動の評価法を整理した。結果:世界38か国において、Health Behaviour in School-aged Children(HBSC)の質問紙が最も多く用いられていた(12か国:31.6%)。次に多く用いられていた質問紙は、Global School-based Student Health Survey(GSHS)であった(6か国:15.8%)。HBSCおよびGSHSの質問紙においては、「1日60分以上の中高強度身体活動を達成した頻度」を尋ね、日常生活全般の身体活動量を評価していた。一方、身体活動の「頻度」および「1日当たりの時間」を把握することで、中高強度身体活動量を算出する質問紙も確認されたが(IPAQ、GPAQ、PAQ-C/A、SHAPES、CLASS、AQuAA)、これらの質問紙を用いた国は少数であった。結論:子ども・青少年における身体活動評価法の国際的な動向として、「1日60分以上の中高強度身体活動を達成した頻度」を尋ねる質問紙(例:HBSC、GSHS)が多く用いられていた。(著者抄録)

Very few community intervention studies that promote physical activity (PA) using guidelines and its dissemination and implementation have been conducted. Consequently, we evaluated the effectiveness of a community-wide intervention (CWI) of PA with adults based on the Japanese guidelines for promoting PA. This was a non-randomized controlled trial, with four administrative districts in Fujisawa city assigned to the intervention group and nine to the control group. The CWI, conducted from 2013 to 2015, comprised information dissemination, education, and community support. The primary outcome was change in PA participation. Secondary outcomes were CWI awareness and PA guideline knowledge. Outcomes were assessed using questionnaires distributed to two independent, random samples of 3000 community-based adults (aged ≥20years). Two separate samples-1230 adults at baseline and 1393 at the two-year follow-up-responded to the survey. The median time spent in PA did not differ between intervention and control groups after adjusting for potential confounders (adjusted difference between groups=-0.02min/day [95% confidence interval (CI): -0.11, 0.10]). However, intervention group participants were more aware of the CWI (33.8%) than were control group participants (25.2%) at the two-year follow-up (odds ratio=1.44 [95% CI: 1.06, 1.95]). A significant difference was also observed in participants' PA guideline knowledge (adjusted difference between groups=0.82% [95% CI: 0.33, 1.31]). Although significant differences in awareness and knowledge were observed between groups, this CWI did not change PA levels over two years. Future studies should investigate the long-term effects of CWIs beyond two years. TRIAL REGISTRATION NUMBER: UMIN-CTR UMIN000018389.

© 2018 Hiroyuki Sasai et al. Background: Physical activity questionnaires (PAQs) used in large-scale Japanese cohorts have rarely been simultaneously validated against the gold standard doubly labeled water (DLW) method. This study examined the validity of seven PAQs used in Japan for estimating energy expenditure against the DLW method. Methods: Twenty healthy Japanese adults (9 men; mean age, 32.4 [standard deviation {SD}, 9.4] years, mainly researchers and students) participated in this study. Fifteen-day daily total energy expenditure (TEE) and basal metabolic rate (BMR) were measured using the DLW method and a metabolic chamber, respectively. Activity energy expenditure (AEE) was calculated as TEE − BMR − 0.1 × TEE. Seven PAQs were self-administered to estimate TEE and AEE. Results: The mean measured values of TEE and AEE were 2,294 (SD, 318) kcal=day and 721 (SD, 161) kcal=day, respectively. All of the PAQs indicated moderate-to-strong correlations with the DLW method in TEE (rho = 0.57–0.84). Two PAQs (Japan Public Health Center Study [JPHC]-PAQ Short and JPHC-PAQ Long) showed significant equivalence in TEE and moderate intra-class correlation coefficients (ICC). None of the PAQs showed significantly equivalent AEE estimates, with differences ranging from −547 to 77 kcal=day. Correlations and ICCs in AEE were mostly weak or fair (rho = 0.02–0.54, and ICC = 0.00–0.44). Only JPHC-PAQ Short provided significant and fair agreement with the DLW method. Conclusions: TEE estimated by the PAQs showed moderate or strong correlations with the results of DLW. Two PAQs showed equivalent TEE and moderate agreement. None of the PAQs showed equivalent AEE estimation to the gold standard, with weak-to-fair correlations and agreements. Further studies with larger sample sizes are needed to confirm these findings.

We aimed to evaluate the associations of individual-level social capital (SC) and physical activity (PA) among Japanese elderly men and women. Individuals aged 65 or above were selected via population-based random sampling of 3000 adults, aged 20 years or above and living in Fujisawa city, who were asked to complete self-administered questionnaires. The sample consisted of 260 men [median (25-75% tile) age 73 (68-78) yrs] and 274 women [73 (68-78) yrs]. The daily duration of PA, SC [e.g., norms of reciprocity (mutual support in the community), social networks (relationship with community people, exchange with other generations), social participation (participation in community organization activities)], socio-economic status [educational attainment, work with income, perceived household economic status], and demographic characteristics [sex, age, living arrangements, BMI, physical limitations] were assessed. Multivariate logistic regression analyses were used to calculate odds ratios (OR) for associations of SC with PA, stratified by sex. High level of mutual support in the community, relationship with community people, and exchange with other generations were associated with longer PA time in men after adjusting for potential confounders in the final model (OR = 2.40 (95% CI: 1.24-4.67), 5.28 (1.42-19.66), and 4.24 (1.15-15.67), respectively). In women, relationship with community people and participation in community organization activities were associated with longer PA time (3.10 (1.32-7.26) and 2.50 (1.27-4.91), respectively). The association of individual-level SC and PA differed between men and women. Future studies can investigate whether similar results can be obtained in other areas or attempt to conduct a large-scale survey.

&lt;p&gt;This study describes relationships between awareness of physical activity (PA) promotion and duration of PA and sedentary behavior (SB) in elderly Japanese. Following a community-wide intervention, 874 individuals 65 years or over were selected via population-based random sampling of 3,000 adults aged 20 years or over living in Fujisawa City, and asked to complete self-administered questionnaires; 550 responded and 373 with data on pertinent variables were included. Forty-eight percent (179/373) stated that they recognized elements of the Japanese PA guidelines such as the &quot;Active Guide&quot; and &quot;+10 (plus ten).&quot; The median duration of PA, of intensity at least equal to walking, and SB among all participants were 100 minutes/day and 300 minutes/day, respectively. Duration of PA did not significantly differ by promotion awareness (Odds Ratio (OR) for ≥100 minutes/day among those aware = 1.02, 95% Confidence Interval (CI) = 0.65-1.62); however, duration of SB did (OR for &lt;300 minutes/day = 1.60, 95% CI = 1.01-2.53). Awareness of PA promotion in elderly Japanese is related to decreased SB, but not increased PA of intensity at least equal to walking.&lt;/p&gt;

The purpose of this study was to clarify the heritability estimates of human muscle strength-related phenotypes (H-2-msp). A systematic literature search was conducted using PubMed (through August 22, 2016). Studies reporting the H-2-msp for healthy subjects in a sedentary state were included. Random-effects models were used to calculate the weighted mean heritability estimates. Moreover, subgroup analyses were performed based on phenotypic categories (eg, grip strength, isotonic strength, jumping ability). Sensitivity analyses were also conducted to investigate potential sources of heterogeneity of H-2-msp, which included age and sex. Twenty-four articles including 58 measurements were included in the meta-analysis. The weighted mean H-2-msp for all 58 measurements was 0.52 (95% confidence intervals [CI]: 0.48-0.56), with high heterogeneity (I-2=91.0%, P&lt;.001). Subgroup analysis showed that the heritability of isometric grip strength, other isometric strength, isotonic strength, isokinetic strength, jumping ability, and other power measurements was 0.56 (95% CI: 0.46-0.67), 0.49 (0.47-0.52), 0.49 (0.32-0.67), 0.49 (0.37-0.61), 0.55 (0.45-0.65), and 0.51 (0.31-0.70), respectively. The H-2-msp decreased with age (P&lt;.05). In conclusion, our results indicate that the influence of genetic and environmental factors on muscle strength-related phenotypes is comparable. Moreover, the role of environmental factors increased with age. These findings may contribute toward an understanding of muscle strength-related phenotypes.

Background-Few data exist on the association between strength training and mortality rates. We sought to examine the association between strength training and all-cause, cardiovascular disease, and cancer mortality.
Methods and Results-Beginning in 2001 to 2005, 28 879 women throughout the United States (average baseline age, 62.2 years) from the Women's Health Study who were free of cardiovascular disease, diabetes mellitus, and cancer reported their physical activities, including strength training. During follow-up (average, 12.0 years) through 2015, investigators documented 3055 deaths (411 from cardiovascular disease and 748 from cancer). After adjusting for covariables, including aerobic activity, time in strength training showed a quadratic association with all-cause mortality (P=0.36 for linear trend; P&lt;0.001 for quadratic trend); hazard ratios across 5 categories of strength training (0, 1-19, 20-59, 60-149, and = 150 min/wk) were 1.0 (referent), 0.73 (95% confidence interval, 0.65-0.82), 0.71(0.62-0.82), 0.81 (0.67-0.97), and 1.10 (0.77-1.56), respectively. A significant quadratic association was also observed for cardiovascular disease death (P=0.007) but not cancer death (P=0.41). Spline models also indicated a J-shaped nonlinear association for all-cause mortality (P=0.020); the point estimates of hazard ratios were &lt;1.00 for 1 to 145 min/wk of strength training, compared with 0 min/wk, whereas hazard ratios were &gt;1.00 for = 146 min/wk of strength training. However, confidence intervals were wide at higher levels of strength training.
Conclusions-Time in strength training showed a J-shaped association with all-cause mortality in older women. A moderate amount of time in strength training seemed beneficial for longevity, independent of aerobic activity; however, any potential risk with more time (approximate to &gt;= 150 min/wk) should be further investigated.

Background: Forkhead box O3A (FOXOA3) and apolipoprotein E (APOE) are arguably the strongest gene candidates to influence human exceptional longevity (EL, i.e., being a centenarian), but inconsistency exists among cohorts. Epistasis, defined as the effect of one locus being dependent on the presence of 'modifier genes', may contribute to explain the missing heritability of complex phenotypes such as EL. We assessed the potential association of epistasis among candidate polymorphisms related to physical capacity, as well as antioxidant defense and cardiometabolic traits, and EL in the Japanese population. A total of 1565 individuals were studied, subdivided into 822 middle-aged controls and 743 centenarians.
Results: We found a FOXOA3 rs2802292 T-allele-dependent association of fibronectin type III domain-containing 5 (FDNC5) rs16835198 with EL: the frequency of carriers of the FOXOA3 rs2802292 T-allele among individuals with the rs16835198 GG genotype was significantly higher in cases than in controls (P &lt; 0.05). On the other hand, among non-carriers of the APOE 'risk' epsilon 4-allele, the frequency of the FDNC5 rs16835198 G-allele was higher in cases than in controls (48.4% vs. 43.6%, P &lt; 0.05). Among carriers of the 'non-risk' APOE epsilon 2-allele, the frequency of the rs16835198 G-allele was higher in cases than in controls (49% vs. 37.3%, P &lt; 0.05).
Conclusions: The association of FDNC5 rs16835198 with EL seems to depend on the presence of the FOXOA3 rs2802292 T-allele and we report a novel association between FNDC5 rs16835198 stratified by the presence of the APOE epsilon 2/epsilon 4-allele and EL. More research on 'gene*gene' and 'gene*environment' effects is needed in the field of EL.

Purpose: Although the benefit of high cardiorespiratory fitness (CRF) for the prevention of type 2 diabetes mellitus (T2DM) is widely accepted, whether consistently high CRF is necessary or transiently high CRF is sufficient is unclear. The present study was conducted to examine the hypothesis that consistently high level of CRF is more beneficial than transiently high CRF for the prevention of T2DM. Methods: This cohort study was conducted in nondiabetic 7158 men age 20 to 60 yr, enrolled from 1986 to 1987. The area under the curve with respect to ground (AUC(G)) for CRF measurements during an 8-yr measurement period (1979-1987) was calculated as an index of integrated CRF level during the period. The differences (Delta AUC(P)) between AUC(G) and peak AUC (peak CRF-measurement period) was also calculated as an index of the presence and the size of a "spike'' in CRF. T2DM was defined by fasting blood glucose and a self-reported diagnosis of diabetes for participants with blood tests. For participants without blood tests, T2DM was defined by the result of oral glucose test after a nonfasting urinary test and a self-reported diagnosis of diabetes. T2DM was determined on health checkups until 2009. Results: During the follow-up period, 1495 men developed T2DM. After adjustment for confounders, as compared with the first quartile of AUC(G) for CRF, the hazard ratio (95% confidence interval) for the second, third, and fourth quartiles were 0.87 (0.76 to 1.00), 0.80 (0.68 to 0.95), and 0.72 (0.58 to 0.89), respectively. For CRF spike, there was no association between Delta AUC(P) in CRF and the incidence of T2DM. Conclusions: Consistently higher level of CRF over time was associated with lower risk of T2DM.

Background: Wii Fit was originally designed as a health and fitness interactive training experience for the general public. There are, however, many examples of Wii Fit being utilized in clinical settings. This article aims to identify the contribution of Wii Fit in the field of health promotion and rehabilitation by: (1) identifying the health-related domains for which the Wii Fit series has been tested, (2) clarifying the effect of Wii Fit in those identified health-related domains and (3) quantifying this effect.
Method: A systematic literature review was undertaken. The MEDLINE database and Games for Health Journal published content were explored using the search term "Wii-Fit." Occurrences resulting from manual searches on Google and material suggested by experts in the field were also considered. Included articles were required to have measurements from Wii Fit activities for at least one relevant health indicator. The effect of Wii Fit interventions was assessed using meta-analyses for the following outcomes: activity-specific balance confidence score, Berg balance score (BBC) and time-up-and-go test (TUG).
Findings: A total of 115 articles highlighted that the Wii Fit has been tested in numerous healthy and pathological populations. Out of these, only a few intervention studies have focused on the prevention of chronic diseases. A large proportion of the studies focus on balance training (N = 55). This systematic review highlights several potential benefits of Wii Fit interventions and these positive observations are supported by meta-analyses data (N = 25). For example, the BBC and the TUG respond to a similar extend to Wii Fit interventions compared with traditional training.
Conclusion: Wii Fit has the potential to be used as a rehabilitation tool in different clinical situations. However, the current literature includes relatively few randomized controlled trials in each population. Further research is therefore required.

身体活動量を調査し,身体不活動を是正することは,公衆衛生学的に非常に重要である。身体活動量の調査手法としては,多くの場合,身体活動質問票(physical activity questionnaires;PAQs)が用いられており,PAQsの中で24時間の行動内容とそれぞれのメッツ値が把握できれば,総エネルギー消費量(total energy expenditure;TEE)を推定できる。TEEは健康アウトカムとの量反応関係を検討するうえで重要な指標であり,さまざまなPAQsからTEEという同一の指標が算出できれば,複数のコホート研究の比較可能性を高めることができる。そこで,本研究では,我が国における代表的なコホート研究で使用されているPAQsを収集し,それぞれのPAQsからTEEを算出するためのスコアリングプロトコルを整理・提案することを目的とした。各コホート研究の代表者らの協力を得て,21のPAQsを収集し,その中でTEEが算出可能な7つのPAQsについて,その特徴とTEE算出方法を詳述した。PAQs間の整合性を考慮すると,各項目に割り当てるメッツ値を修正する必要があったり,公式なスコアリングプロトコルでは割り当てるメッツ値が定められていなかったりするなど,改善が必要な点が残されている。今後は,この点についての議論を深めるとともに,本研究で整理・提案したTEE算出のためのスコアリングプロトコルの妥当性を検討していくことが必要である。(著者抄録)

Background: This study aimed to develop and cross-validate prediction equations for estimating appendicular skeletal muscle mass (ASM) and to examine the relationship between sarcopenia defined by the prediction equations and risk factors for cardiovascular diseases (CVD) or osteoporosis in Japanese men and women.
Methods: Subjects were healthy men and women aged 20-90 years, who were randomly allocated to the following two groups: the development group (D group; 257 men, 913 women) and the cross-validation group (V group; 119 men, 112 women). To develop prediction equations, stepwise multiple regression analyses were performed on data obtained from the D group, using ASM measured by dual-energy X-ray absorptiometry (DXA) as a dependent variable and five easily obtainable measures (age, height, weight, waist circumference, and handgrip strength) as independent variables.
Results: When the prediction equations for ASM estimation were applied to the V group, a significant correlation was found between DXA-measured ASM and predicted ASM in both men and women (R-2 = 0.81 and R-2 = 0.72). Our prediction equations had higher R-2 values compared to previously developed equations (R-2 = 0.75-0.59 and R-2 = 0.69-0.40) in both men and women. Moreover, sarcopenia defined by predicted ASM was related to risk factors for osteoporosis and CVD, as well as sarcopenia defined by DXA-measured ASM.
Conclusions: In this study, novel prediction equations were developed and cross-validated in Japanese men and women. Our analyses validated the clinical significance of these prediction equations and showed that previously reported equations were not applicable in a Japanese population.

Background: Appendicular skeletal muscle (or lean) mass (ALM) estimated using dual-energy X-ray absorptiometry (DXA) is considered to be a preferred method for sarcopenia studies. However, DXA is expensive, has limited portability, and requires radiation exposure. Bioelectrical impedance analysis (BIA) is inexpensive, easy to use, and portable, thus BIA might be useful in sarcopenia investigations. However, a large variety of models have been commercially supplied by different companies, and for most consumer products, the equations estimating ALM are not disclosed. It is therefore difficult to use these equations for research purposes. In particular, the BIA equation is often age-dependent, which leads to fundamental difficulty in examining age-related ALM loss. The aims of the current study were as follows: (1) to develop and validate an equation to estimate ALM using multi-frequency BIA (MF-BIA) based on theoretical models, and (2) to establish sarcopenia cutoff values using the equation for the Japanese population. Methods: We measured height (Ht), weight, and ALM obtained using DXA and a standing-posture 8-electrode MF-BIA (5, 50, 250 kHz) in 756 Japanese individuals aged 18 to 86-years-old (222 men and 301 women as developing equation group and 97 men and 136 women as a cross validation group). The traditional impedance index (Ht2/Z50) and impedance ratio of high and low frequency (Z250/Z5) of hand to foot values were calculated. Multiple regression analyses were conducted with ALM as dependent variable in men and women separately. Results: We created the following equations: ALM = (0.6947 × (Ht2/Z50)) + (-55.24 × (Z250/Z5)) + (-10,940 × (1/Z50)) + 51.33 for men, and ALM = (0.6144 × (Ht2/Z50)) + (-36.61 × (Z250/Z5)) + (-9332 × (1/Z50)) + 37.91 for women. Additionally, we conducted measurements in 1624 men and 1368 women aged 18 to 40 years to establish sarcopenia cutoff values in the Japanese population. The mean values minus 2 standard deviations of the skeletal muscle mass index (ALM/Ht2) in these participants were 6.8 and 5.7 kg/m2 in men and women, respectively. Conclusions: The current study established and validated a theoretical and age-independent equation using MF-BIA to estimate ALM and provided reasonable sarcopenia cutoff values.

Hand grip strength is a widely used proxy of muscular fitness, a marker of frailty, and predictor of a range of morbidities and all-cause mortality. To investigate the genetic determinants of variation in grip strength, we perform a large-scale genetic discovery analysis in a combined sample of 195,180 individuals and identify 16 loci associated with grip strength (P&lt;5 x 10(-8)) in combined analyses. A number of these loci contain genes implicated in structure and function of skeletal muscle fibres (ACTG1), neuronal maintenance and signal transduction (PEX14, TGFA, SYT1), or monogenic syndromes with involvement of psychomotor impairment (PEX14, LRPPRC and KANSL1). Mendelian randomization analyses are consistent with a causal effect of higher genetically predicted grip strength on lower fracture risk. In conclusion, our findings provide new biological insight into the mechanistic underpinnings of grip strength and the causal role of muscular strength in age-related morbidities and mortality.

Background: Appendicular skeletal muscle (or lean) mass (ALM) estimated using dual-energy X-ray absorptiometry (DXA) is considered to be a preferred method for sarcopenia studies. However, DXA is expensive, has limited portability, and requires radiation exposure. Bioelectrical impedance analysis (BIA) is inexpensive, easy to use, and portable; thus BIA might be useful in sarcopenia investigations. However, a large variety of models have been commercially supplied by different companies, and for most consumer products, the equations estimating ALM are not disclosed. It is therefore difficult to use these equations for research purposes. In particular, the BIA equation is often age-dependent, which leads to fundamental difficulty in examining age-related ALM loss. The aims of the current study were as follows: (1) to develop and validate an equation to estimate ALM using multi-frequency BIA (MF-BIA) based on theoretical models, and (2) to establish sarcopenia cutoff values using the equation for the Japanese population. Methods: We measured height (Ht), weight, and ALM obtained using DXA and a standing-posture 8-electrode MF-BIA (5, 50, 250 kHz) in 756 Japanese individuals aged 18 to 86-years-old (222 men and 301 women as developing equation group and 97 men and 136 women as a cross validation group). The traditional impedance index (Ht(2)/Z(50)) and impedance ratio of high and low frequency (Z(250)/Z(5)) of hand to foot values were calculated. Multiple regression analyses were conducted with ALM as dependent variable in men and women separately. Results: We created the following equations: ALM = (0.6947 x (Ht(2)/Z(50))) + (-55.24 x (Z(250)/Z(5))) + (-10,940 x (1/Z(50))) + 51.33 for men, and ALM = (0.6144 x (Ht(2)/Z(50))) + (-36.61 x (Z(250)/Z(5))) + (-9332 x (1/Z(50))) + 37.91 for women. Additionally, we conducted measurements in 1624 men and 1368 women aged 18 to 40 years to establish sarcopenia cutoff values in the Japanese population. The mean values minus 2 standard deviations of the skeletal muscle mass index (ALM/Ht(2)) in these participants were 6.8 and 5.7 kg/m(2) in men and women, respectively. Conclusions: The current study established and validated a theoretical and age-independent equation using MF-BIA to estimate ALM and provided reasonable sarcopenia cutoff values.

Metagenomic analysis based on the 16S rRNA gene is generally performed to examine the diversity and abundance of commensal bacteria in feces, which is now recognized to be associated with human health and diseases. Guanidine thiocyanate (GuSCN) solution is used as a less onerous way compared with a frozen method to transport and stock fecal samples at room temperature for DNA analysis; however, optimal methods to measure fecal bacterial composition in GuSCN solution remain to be investigated. Here, we examined the influence of various factors such as pretreatment (e.g., removing GuSCN solution and washing feces with phosphate-buffered saline (PBS) before mechanical lysis), fecal concentration in the GuSCN solution, storage time, and position of fecal subsampling on the 16S rRNA-based analysis of fecal bacteria in GuSCN solution. We found that pretreatment and fecal concentration affected the bacterial composition, and a little change was noted with subsampling position. Based on these results, we propose a basic protocol, including fecal sampling, sample storage, and DNA extraction, for the 16S rRNA-based analysis of bacterial composition in feces suspended in GuSCN solution.

Purpose: Having a low level of physical fitness, especially cardiorespiratory fitness, appears to accelerate age-related aortic stiffening. Whereas, some studies have reported that trunk flexibility is a component of physical fitness, it is also negatively associated with arterial stiffening independent of cardiorespiratory fitness in cross-sectional studies. However, no long-term longitudinal study has determined whether poor trunk flexibility accelerates the progression of age-related aortic stiffening. We examined trunk flexibility and aortic stiffness progression in a 5-year longitudinal study.
Methods and Results: A total of 305 apparently healthy men and women participated in this study (49.6 +/- 9.5 years of age). Trunk flexibility was measured using a sit-and-reach test. Aortic stiffness was assessed using carotid-femoral pulse wave velocity (cfPWV) at baseline and after 5 years. Analysis of covariance (ANCOVA) was used to assess the association of the annual rate of cfPWV across flexibility levels (low, middle, high). There were no significant differences in baseline cfPWV among the three groups (835 164, 853 +/- 140, 855 +/- 2.68 cm/s; P = 0.577). Annual AcfPWV was significantly higher in the low-flexibility group than in the high-flexibility group (P = 0.009). ANCOVA revealed an inverse relationship between flexibility level and annual AcfPWV (14.41 +/- 2.73, 9.79 +/- 2.59, 2.62 +/- 2.68 cm/s/year: P for trend = 0.011). Multiple regression analysis revealed that baseline sit and reach (beta = 0.12, -0.70 to -0.01) was independently correlated with AcfPWV following adjustment for baseline peak oxygen uptake, age, sex, body fat, heart rate, and cfPWV. The 5-year change in cfPWV was not significantly correlated with 5-year change in sit-and-reach performance (P = 0.859).
Conclusion: Poor trunk flexibility is associated with greater progression of age-related aortic stiffening in healthy adults. However, we failed to confirm a significant association between 5-year change in aortic stiffness and 5-year change in trunk flexibility. The association between increased age-related increase in aortic stiffness and deterioration in flexibility due to age may require observation for more than 5 years.

alpha-Actinin-3 (ACTN3) R577X polymorphism is associated with muscular strength and power. This study was performed to investigate the association between ACTN3 R577X polymorphisms and flexibility as another component of fitness in 2 cohorts. Cohort 1 consisted of 208 men and 568 women (ages 23-88), while Cohort 2 consisted of 529 men and 728 women (ages 23-87). All participants were recruited from the Tokyo metropolitan area and underwent a battery of tests to assess their grip strength and sit-and-reach flexibility. Genotyping results were analyzed for ACTN3 (rs1815739) polymorphism using the TaqMan approach. In Cohort 1, sit-and-reach in the RR genotype (35.3 +/- 0.7 cm) was significantly lower than those in the RX and XX genotypes (37.2 +/- 0.3 cm) even after adjusting for sex, age, and exercise habit as covariates (P &lt; 0.01). In Cohort 2, sit-and-reach tended to be lower in RR (38.1 +/- 0.6 cm) than in RX and XX (39.1 +/- 0.3 cm), but the differences were not significant (P = 0.114). Analysis in pooled subjects indicated that RR was associated with significantly lower flexibility than RX and XX (P = 0.009). The RR genotype of ACTN3 R577X in the general Japanese population showed lower flexibility compared to the RX and XX genotypes.

我々は,肥満者に対する行動科学的手法を用いた減量プログラム(佐久肥満克服プログラム)を開発し,無作為化比較対照試験および1年間の追跡により,その有効性を明らかにしてきた。本資料論文では,日本運動疫学会プロジェクト研究「介入研究によるエビデンスの『つくる・伝える・使う』の促進に向けた基盤整備」の一環として,減量プログラムのエビデンスを提供し,プログラムの一般化可能性についてRE-AIMの観点から検討を行った。本減量プログラムは,食事や身体活動の改善に関する目標を対象者自身が考え,日常生活において実践できるよう,医師,管理栄養士,健康運動指導士が連携し支援を行うものであった。対象は,人間ドック受診者における肥満者であり,プログラムの到達度は24.1%であった。介入群の対象者では,プログラムにより,体重等の減少やその維持が認められた。本プログラムは特別な施設等を必要とせず比較的容易に実施することが可能であるが,今回総勢19名もの管理栄養士・健康運動指導士が指導に携わり,その多くが研究所のスタッフであったこと,介入に多くの時間を要したことを考えると,通常の保健指導の現場へそのまま適用するのは困難であると考えられる。したがって,今後,今回得られた成果から介入手法の中で効果的であったものを明確にし,それを現場の予算に応じて活用していくことが重要だと考えられる。(著者抄録)

Background: This study aimed to compare relationships between height- or weight-adjusted appendicular skeletal muscle mass (ASM/Ht2 or ASM/Wt) and risk factors for cardiometabolic diseases or osteoporosis in Japanese men and women.
Methods: Subjects were healthy Japanese men (n = 583) and women (n = 1218). The study population included a young group (310 men and 357 women; age, 18-40 years) and a middle-aged and elderly group (273 men and 861 women; age, = 41 years). ASM was measured by dual-energy X-ray absorptiometry. The reference values for class 1 and 2 sarcopenia in each sex were defined as values one and two standard deviations below the sex-specific means of the young group, respectively.
Results: The reference values for class 1 and 2 sarcopenia defined by ASM/Ht(2) were 7.77 and 6.89 kg/m(2) in men and 6. 06 and 5.31 kg/m(2) in women, respectively. The reference values for ASM/Wt were 35.0 and 32.0% in men and 29.6 and 26.4% in women, respectively. In both men and women, ASM/Wt was negatively correlated with higher triglycerides (TG) and positively correlated with serum high-density lipoprotein cholesterol (HDL-C), but these associations were not found in height-adjusted ASM. In women, TG, systolic blood pressure, and diastolic blood pressure in sarcopenia defined by ASM/Wt were significantly higher than those in normal subjects, but these associations were not found in sarcopenia defined by ASM/Ht(2). Whole-body and regional bone mineral density in sarcopenia defined by ASM/Ht(2) were significantly lower than those in normal subjects, but these associations were not found in sarcopenia defined by ASM/Wt.
Conclusions: Weight-adjusted definition was able to identify cardiometabolic risk factors such as TG and HDL-C while height-adjusted definition could identify factors for osteoporosis.

© The Author(s). Background: This study aimed to develop and cross-validate prediction equations for estimating appendicular skeletal muscle mass (ASM) and to examine the relationship between sarcopenia defined by the prediction equations and risk factors for cardiovascular diseases (CVD) or osteoporosis in Japanese men and women. Methods: Subjects were healthy men and women aged 20-90 years, who were randomly allocated to the following two groups: the development group (D group; 257 men, 913 women) and the cross-validation group (V group; 119 men, 112 women). To develop prediction equations, stepwise multiple regression analyses were performed on data obtained from the D group, using ASM measured by dual-energy X-ray absorptiometry (DXA) as a dependent variable and five easily obtainable measures (age, height, weight, waist circumference, and handgrip strength) as independent variables. Results: When the prediction equations for ASM estimation were applied to the V group, a significant correlation was found between DXA-measured ASM and predicted ASM in both men and women (R 2 = 0.81 and R 2 = 0.72). Our prediction equations had higher R 2 values compared to previously developed equations (R 2 = 0.75-0.59 and R 2 = 0.69-0.40) in both men and women. Moreover, sarcopenia defined by predicted ASM was related to risk factors for osteoporosis and CVD, as well as sarcopenia defined by DXA-measured ASM. Conclusions: In this study, novel prediction equations were developed and cross-validated in Japanese men and women. Our analyses validated the clinical significance of these prediction equations and showed that previously reported equations were not applicable in a Japanese population.

[Purpose] This study evaluated whether obesity is a risk factor for low back pain, by using body fat percentage (%FAT) and body mass index (BMI) as indices of obesity among Japanese males. [Subjects and Methods] This study included 1,152 males (average age: 28.0 ± 4.6 years). BMI was calculated from subject’s height and weight, and %FAT was estimated by the thickness of two parts of skin. Low back pain, drinking and smoking were surveyed using a self-administered questionnaire, and maximal oxygen uptake was measured by a submaximal exercise test using a cycle ergometer. [Results] A significant positive dose-response relationship was shown between %FAT and persistent low back pain prevalence. Similarly, a significant positive dose-response relationship was confirmed between BMI and persistent low back pain. [Conclusion] This study suggests that both high %FAT and BMI are risk factors for persistent low back pain.

Background and Objectives: The purpose of the present study was to determine whether depression was associated with metabolic syndrome and unhealthy behaviours in community residents. Methods and Study Design: Using the 2009-2010 baseline data of the Saku Cohort Study, 1,225 men and women who participated in a community health screening were included in the cross-sectional analyses. Depression was assessed using the Zung Self-Rating Depression Scale. Consistent with the Japanese Society of Internal Medicine's definition, we defined metabolic syndrome as abdominal obesity plus two or more of the following: high blood pressure, hyperglycaemia, and dyslipidaemia. We defined 'pre- and metabolic syndrome' as the presence of one or more of the three criteria in addition to abdominal obesity. Results: There was no significant association between depression and metabolic syndrome. In women, the prevalence of pre- and metabolic syndrome was significantly higher in the depression group than that in the non-depression group (17.5% vs 9.5%, p=0.046), whereas no such significant association was observed in men. Logistic regression analysis showed that depression was associated with unhealthy behavioural factors differently in men and women. Conclusions: This study revealed that depression was associated with several unhealthy behavioural factors in both men and women, but depression was associated with pre- and metabolic syndrome only in women. These findings suggest that depression may be a warning sign of metabolic syndrome in women with unhealthy behavioural factors. Psychological factors should be considered in addition to the assessment of physical status.

Objectives: This study aimed to examine the association between a total genotype score (TGS) based on previously published genetic polymorphism candidates and differences in sprint/power performance.
Design: Case-control association study.
Methods: We analysed 21 polymorphisms, which have previously been associated with sprint/power performance and related phenotypes, in 211 Japanese sprint/power track and field athletes (77 regional, 72 national, and 62 international athletes) and 649 Japanese controls using the TaqMan SNP genotyping assay. We calculated the TGS (maximum value of 100 for the theoretically optimal polygenic score) for the 21 polymorphisms.
Results: All groups exhibited similar TGSs (control: 55.9 +/- 7.2, regional: 55.1 +/- 7.1, national: 56.1 +/- 7.4, and international: 56.0 +/- 7.8, p=0.827 by one-way analysis of variance). Nine of the 21 polymorphisms had the same direction of effect (odds ratio &gt;1.0) as in previous studies, while 12 had the opposite direction of effect (odds ratio &lt;1.0). Three polymorphisms (rs699 in AGT, rs41274853 in CNTFR, and rs7832552 in TRHR), which had the same direction of effect as in previous studies, were associated with international sprint/power athlete status (p&lt;0.05). However, after multiple testing corrections, the statistical significance of these polymorphisms was not retained.
Conclusions: These results suggest that TGSs based on the 21 previously published sprint/power performance-associated polymorphisms did not influence the sprint/power athlete status of Japanese track and field athletes. However, our results maintain the possibility that three of these polymorphisms might be associated with sprint/power performance. (C) 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

The purpose of this study was to investigate the effects of the MCT1 T1470A polymorphism (rs1049434) on power-oriented performance and lactate concentration during or after cycling sprints in Japanese wrestlers. Participants (199 wrestlers and 649 controls) were genotyped for the MCT1 T1470A genotype (rs1049434) using the TaqMan (R) Assay. All wrestlers were international (n = 77) or national (n = 122) level athletes. Among them, 46 wrestlers performed 2 anaerobic performance tests, a 30-s Wingate Anaerobic test (WAnT) and a series of 10 maximal effort 10-s sprints on a cycle ergometer. Blood lactate levels were measured before, during, and after the tests. In the A-allele recessive model (AA vs. TA + TT), the frequency of the AA genotype was significantly higher in all wrestlers than in controls (p = 0.037). Wrestlers with AA genotype had lower blood lactate concentrations than those with TA + TT genotype at 10 min after the WAnT and following the 5th and the final set of repeated cycling sprints (p &lt; 0.05). The AA genotype of the MCT1 T1470A polymorphism is over-represented in wrestlers compared with controls and is associated with lower blood lactate concentrations after 30-s WAnT and during intermittent sprint tests in Japanese wrestlers.

Myostatin (MSTN) and alpha-actinin-3 (ACTN3) genes are potentially associated with preservation of muscle mass and oxidative capacity, respectively. To explore the possible role of these genes in exceptional longevity (EL), the allele/genotype frequency distribution of two polymorphisms in MSTN (rs1805086, K153R) and ACTN3 (rs1815739, R577X) was studied in Japanese centenarians of both sexes (n = 742) and healthy controls (n = 814). The rs1805086 R-allele (theoretically associated with muscle mass preservation at the expense of oxidative capacity) was virtually absent in the two groups, where genotype distributions were virtually identical. Likewise, no differences in allele (p = 0.838 (women); p = 0.193 (men); p = 0.587 (both sexes)) or genotype distribution were found between groups for ACTN3 rs1815739 (p = 0.975 (women), p = 0.136 (men), p = 0.752 (both sexes)). Of note, however, the frequency of the rs1805086 R-allele observed here is the lowest been reported to date whereas that of the 'highly oxidative/efficient' rs1815739 XX genotype in Japanese male centenarians (33.3%) or supercentenarians of both sexes (&gt;= 110 years) are the highest (32.6%), for a non-American population. No definite conclusions can be inferred in relation to EL owing to its lack of association with both rs1815739 and rs1805086. However, it cannot be excluded that these gene variants could eventually be related to a "healthy" metabolic phenotype in the Japanese population. Further research might determine if such metabolic profile is among the factors that can potentially predispose these individuals to live longer than Caucasians and what genetic variants might be actually involved.

The aim of this study was to examine a polygenic profile related to endurance performance, based on current knowledge, in the Japanese population. We analyzed 21 genetic polymorphisms that have been reported to be associated with endurance performance and its related phenotypes in 175 endurance runners (60 international-, 94 national-, and 21 regional-level) and 649 controls in the Japanese population. Then, we calculated the total genotype score (TGS) (maximum value of 100 for the theoretically optimum polygenic score) for endurance performance. There was no association between the TGS and endurance athlete status (Control: 49.0 ± 7.6, Regional: 47.3 ± 7.6, National: 49.1 ± 5.7, and International: 48.2 ± 7.0, P = 0.626). These results suggested that TGSs based on the 21 previously published endurance performance-associated polymorphisms do not influence endurance running performance in the Japanese population. Nevertheless, some marginal tendencies have to be noted: the frequencies of the ACTN3 R577X rs1815739 RR+RX genotype and the GNB3 rs5443 CC+CT genotype were higher in international athletes than in controls (85% vs. 73.6%, P = 0.042 and 90% vs. 76%, P = 0.007, respectively), but not significantly different after Bonferroni correction.

Objectives: Previous studies have indicated that the rs2802292 polymorphism in the human forkhead box O3A (FOXO3A) gene might be associated with exceptional longevity (EL, i.e., living 100+ years), although the results are conflicting.
Study design and main outcome measures: Using a case-control design, we investigated the distribution of the rs2802292 polymorphism in two ethnically distinct cohorts of centenarians (cases) and younger adults (controls). The first cohort included Japanese individuals (733 centenarians and 820 controls) and the second was from Northern Italy (79 disease-free centenarians and 316 controls).
Results: No statistically significant association was found between the rs2802292 polymorphism and EL in either cohort (either examined in their entirety or in a sex-based analysis).
Conclusions: In light of our negative findings, further research and resequencing efforts are needed to shed more light on the potential association between EL and FOXO3A polymorphisms. (C) 2016 Published by Elsevier Ireland Ltd.

Aim: Recent meta-analyses of the literature confirmed the association between the RR+RX genotype of the ACTN3 R577X polymorphism and elite sprint/power athletic status in Europeans but not in Asians and Africans, while the association between the R577X genotype and elite endurance athlete status is less convincing. The aim of the present study was to investigate the association between the ACTN3 R577X genotype and elite athlete status in a large Asian (Japanese) cohort of track and field athletes. Methods: One-thousand fifty-seven Japanese track and field athletes (627 sprint/power athletes and 430 endurance athletes) and 810 Japanese controls were genotyped for the ACTN3 R577X polymorphism (rs1815739) by using the TaqMan (R) SNP Genotyping Assay. Results: Elite sprint/power athletes had a higher frequency of the RR+RX genotype than the controls (OR: 1.59, 95% CI: 1.16-2.18; P=.003). A significant linear correlation was found between the RR+RX genotype and athlete status (i.e. regional&lt;national&lt;international) in sprint/power athletes (regional: 71%, national: 81%, international: 84%; P=.001 for trend) and long-distance runners (regional: 65%, national: 72%, international: 82%; P=.030 for trend). Conclusions: The data obtained for this large Asian (Japanese) cohort of track and field athletes served to confirm the association between the RR+RX genotype of the ACTN3 R577X polymorphism and elite sprint/power athlete status and also the association between the ACTN3 RR+RX genotype and long-distance running athletic status.

目的 健康日本21(第二次)の推進のため、国民全体から無作為抽出した集団を対象に、平成25〜26年にかけて電話調査を実施し、健康日本21(第二次)に関する健康意識・認知度を調査した。方法 乱数番号法を用いて、全国の20歳代から70歳以上の10歳年齢階級別に男女各150人、計1,800人より回答を得た。調査項目は1)用語の認知度(「健康日本21」、「健康寿命」、「メタボリックシンドローム(MetS)」、「慢性閉塞性肺疾患(COPD)」、「ロコモティブシンドローム」、「アクティブガイド」、「WHOのたばこ規制枠組み条約」、「スマートライフプロジェクト」)、2)健康意識(「最近1年間の健診受診歴」、「喫煙状況」、「健康のために望ましいと思う1日の野菜摂取量」)とし、調査回答の単純集計および性別・年齢階級別のクロス集計を行った。上記1)に対して、「意味を含めて知っている」と「聞いたことはあるがよく知らない」の回答者の割合を認知度とした。また、平成25、26年の年次比較、および男女・年齢階級間比較にはχ2検定を用いた。結果 平成25年で認知度が高かった上位5項目は、「MetS」(96.2%)、「COPD」(51.1%)、「健康寿命」(34.2%)、「ロコモティブシンドローム」(30.2%)、「WHOたばこ規制枠組み条約」(28.0%)であった。年次比較では「健康寿命」、「ロコモティブシンドローム」、「アクティブガイド」の認知度が平成25年より平成26年で有意に高かった。また、「1日の望ましい野菜摂取量」を350g程度と正答できた割合は、平成25年の41.6%と比べ、平成26年で50.1%と有意に高かった。平成25年で「健康寿命」、「COPD」、「ロコモティブシンドローム」の認知度や「1日の望ましい野菜摂取量」の正答割合は、男性より女性で有意に高かった。また、同年で「MetS」、「COPD」、「健康寿命」、「ロコモティブシンドローム」の認知度や「1日の望ましい野菜摂取量」の正答割合は年齢階級間に有意差があった。結論 「健康寿命」と「ロコモティブシンドローム」の認知度や健康意識に関わる「1日の望ましい野菜摂取量」の正答割合は、平成25年より平成26年で有意に高かった。また、項目ごとに認知度や健康意識の低かった性や年齢階級をターゲットにした介入が必要であると考えられた。(著者抄録)

While heavier weight is known to increase the incidence of dyslipidemia, limited data are available on the relationship between weight gain and its development.
A total of 2647 males were categorized into the following four groups according to the difference between their self-reported weight at 20 years of age and their measured weight in 1994-95: a loss of a parts per thousand yen5% (decrease), loss of &lt; 5% or gain of &lt; 5% (no change), gain of a parts per thousand yen5 to &lt; 15% (increase) and gain of a parts per thousand yen15% (sizable increase). They were followed up until their 2002-03 health examination. Using the 'no change' group as reference, the multivariable-adjusted odds ratio (adjusted for age, body mass index at 20 years of age, physical activity, smoking and alcohol intake) and 95% confidence interval (95% CI) for the incidence of dyslipidemia were determined using logistic regression models.
A total of 1342 participants developed dyslipidemia during the follow-up period. The 'increase' and 'sizable increase' groups had odds ratios for the incidence of dyslipidemia of 1.97 (95% CI, 1.59-2.45) and 2.68 (2.15-3.34), respectively, demonstrating that there was a significant dose-response association between weight gain since 20 years of age and the incidence of dyslipidemia (P &lt; 0.001 for trend).
These results suggest that dyslipidemia could be prevented by avoiding weight gain in adulthood.

Physical activity has multiple health benefits but may also increase the risk of developing musculoskeletal pain (MSP). However, the relationship between physical activity and MSP has not been well characterized. This study examined the dose-response relationship between sports activity and MSP among adolescents. Two school-based serial surveys were conducted 1 year apart in adolescents aged 12 to 18 years in Unnan, Japan. Self-administered questionnaires were completed by 2403 students. Associations between time spent in organized sports activity and MSP were analyzed cross-sectionally (n=2403) and longitudinally (n=374, students free of pain and in seventh or 10th grade at baseline) with repeated-measures Poisson regression and restricted cubic splines, with adjustment for potential confounders. The prevalence of overall pain, defined as having pain recently at least several times a week in at least one part of the body, was 27.4%. In the cross-sectional analysis, sports activity was significantly associated with pain prevalence. Each additional 1 h/wk of sports activity was associated with a 3% higher probability of having pain (prevalence ratio=1.03, 95% confidence interval=1.02-1.04). Similar trends were found across causes (traumatic and nontraumatic pain) and anatomic locations (upper limbs, lower back, and lower limbs). In longitudinal analysis, the risk ratio for developing pain at 1-year follow-up per 1 h/wk increase in baseline sports activity was 1.03 (95% confidence interval = 1.02-1.05). Spline models indicated a linear association (P&lt;0.001) but not a nonlinear association (P &gt;= 0.45). The more the adolescents played sports, the more likely they were to have and develop pain.

The aim of this study was to investigate whether rs41274853 in the 3'-untranslated region of the ciliary neurotrophic factor receptor gene (CNTFR) is associated with elite sprint/power athletic status and assess its functional significance. A total of 211 Japanese sprint/power track and field athletes (62 international, 72 national, and 77 regional athletes) and 814 Japanese controls were genotyped at rs41274853. Luciferase reporter assay was conducted to investigate whether this C-to-T polymorphism affects binding of microRNA miR-675-5p to this region. The TT genotype was significantly more frequent among international sprint/power athletes (19.4 %) than in the controls after Bonferroni correction (7.9 %, P = 0.036, OR = 2.81 [95 % CI: 1.43-5.55]). Furthermore, in non-athletic young/middle-aged men (n = 132), TT genotype carriers exhibited significantly greater leg extension power (26.6 +/- 5.4 vs. 24.0 +/- 5.4 W/kg BW, P = 0.019) and vertical jump performance (50.1 +/- 6.9 vs. 47.9 +/- 7.5 cm, P = 0.047) than the CC + CT genotype carriers. Reporter assays revealed that the miR-675-5p binds to this polymorphic region within the CNTFR mRNA, irrespective of the rs41274853 allele present. Although the functional significance of the rs41274853 polymorphism remains unclear, the CNTFR is one of the candidate genes contributing to sprint/power performance.

目的 本研究は、地方都市在住の成人および高齢者を対象に郵便番号によって評価された客観的な自宅近隣施設環境と加速度センサー付活動量計によって客観的に評価された身体活動量との関係を横断的に検討することを目的とした。方法 本研究は、佐久健康長寿プロジェクトの中間解析であり、佐久市に居住しデータの欠損がない30〜84歳の男女1,274人(男性721人、女性553人)を対象とした。身体活動量に関連する自宅近隣施設環境については、駅、スーパーマーケット・コンビニエンスストア、郵便局・銀行、病院・診療所、役所・公民館、文化施設・児童館、公園、公共・民間スポーツ施設について、佐久市役所の公式ホームページおよびNTTが発行しているタウンページのインターネット版iタウンページから、住所と郵便番号を抽出し、郵便番号別に整理した。対象者の身体活動量は、3次元加速度センサー付活動量計を用いて測定し、1日の平均歩数と1週間の中強度以上(3メッツ以上)の活動量について算出した。そして、施設環境を対象者の自宅住所の郵便番号と関連づけ、身体活動量との関係を検討した。分析は、65歳未満と65歳以上の年齢グループ別に、健康日本21(第二次)で設定されている目標歩数と中強度以上の活動量23メッツ・時/週の2つの身体活動量の目標値をそれぞれ従属変数、自宅近隣施設環境を独立変数、満年齢、性別、Body Mass Indexを調整変数とした多重ロジスティック回帰分析を実施した。結果 身体活動量と自宅近隣施設環境の関連は、65歳未満で、週に23メッツ・時の中強度以上の活動量を満たしていることとスーパーマーケット・コンビニエンスストアの数が多いことが統計学的に有意な関連を示した。65歳以上では、健康日本21(第二次)の目標歩数を満たしていることと郵便局・銀行の数が、中強度以上の活動量の目標値(23メッツ・時/週)を満たしていることとスーパーマーケット・コンビニエンスストアの数が統計学的に有意な正の関連を示した。結論 本研究の結果から、買い物や生活に必要な自宅近隣の施設の充実は、身体活動量の多いことと関連することが示唆された。(著者抄録)

生活習慣病に対する身体活動・運動の有効性は多くのエビデンスによって明らかにされている。高齢者が身体活動・運動を行う際には、事前にメディカルチェックを受け、これまでの運動歴や現在の運動習慣によって、個人の体力に応じた運動・身体活動を選択させることが重要である。ヨガやストレッチングなど低強度の運動による血圧・動脈硬化・糖代謝改善効果や、掃除や家事など高齢者でも続けやすい身体活動から生活習慣病予防・改善を考えることも注目されている。(著者抄録)

Cardiorespiratory fitness is negatively associated with arterial stiffness, although it is unclear whether it is associated with prospective arterial stiffness changes. The authors examined cardiorespiratory fitness and arterial stiffness progression in a 2-year follow-up study of 470 healthy men and women aged 26 to 69 years. Peak oxygen uptake (VO2peak) was measured at baseline using a graded cycle exercise test. Arterial stiffness was assessed using brachialankle pulse wave velocity (baPWV) at baseline and after 2 years. Two-year changes in baPWV were significantly higher in patients in the lowest VO2peak tertile (28.8 +/- 7.6 cm/ s) compared with those in the highest VO2peak tertile (-1.4 +/- 7.5 cm/ s) (P=.024) and were inversely correlated with VO2peak (r=-.112, P=.015). Stepwise multiple regression analysis revealed that age, glucose, baPWV, VO2peak, and sex were independent correlates of 2-year changes in baPWV, suggesting that higher cardiorespiratory fitness is associated with age-related arterial stiffening suppression. J Clin Hypertens (Greenwich). 2016; 18: 292-298. (C) 2015 Wiley Periodicals, Inc.

© 2016, Senpuku et al. Physical fitness is an indicator of systemic well-being in humans. Little is known about the role of physical fitness for maintaining systemic health in the elderly. Here, we study elderly subjects to determine the relationships between physical fitness and CD56 and CD16 surface NK cell markers on peripheral blood lymphocytes, as well as to analyze the relationship between the surface markers and incidence of death. We selected 253 independent elderly subjects (122 female; 131 male) who were 79–80 years old. Subjects having a higher proportion of CD56dimCD16high within CD56+CD16+ cells, or ration of CD56dimCD16high and CD56dimCD16− cells had a significant positive correlation with maximum bilateral knee extensor strength/weight (kg) (r = 0.425; P &lt; 0.0001 or r = 0.323; P &lt; 0.0001). In contrast, an increased proportion of CD56brightCD16− cells within lymphocyte significantly negatively correlated with the maximum bilateral knee extensor strength/weight (kg) (r = −0.290; P = 0.0004); and these subjects had a significantly lower mortality during the 5 years following measurement of death. Therefore, we found that a synergistic effect of the right and left leg muscle strength was associated with proportion of matured NK and NKT cells and induced a low proportion of CD56brightCD16− cells within lymphocyte. Moreover, the low proportion of CD56brightCD16− cells was associated with incidence of death. In conclusion, measurements of physical fitness, the proportion of CD56dimCD16high within CD56+CD16+ cells, the ratio of CD56dimCD56high and CD56dimCD16− cells, and the proportion of CD56brightC16− cells in lymphocytes are important indicators to check elderly health.

Objectives The aim of this study was to examine the association between the number of neighborhood facilities that were assessed according to postal code and objectively measured physical activity by using an accelerometer in community-dwelling Japanese people.Methods The participants included 1,274 Japanese people aged 30-84 years from the Saku cohort study. As neighborhood facilities related to physical activity, we extracted information regarding train stations, supermarkets/convenience stores, postal offices/banks, hospitals/clinics, public offices/community centers, cultural facilities/public children's houses, parks, and sports facilities by using each participant's postal code from the online version of the iTownPages directory published by Nippon Telegraph and Telephone Corporation (NTT) and the official homepage of the Saku City Government Office. We measured each participant's physical activity level using an accelerometer, and calculated the average daily step count and the average weekly period of moderate-to-vigorous intensity (≥3 metabolic equivalents of tasks [METs]) physical activity. The association between two selected physical activity-related variables and the numbers of eight types of neighborhood facilities were analyzed by multivariate logistic regression analysis for people aged 30-64 years and for those aged over 65 years.Results On multivariate logistic regression analysis, meeting the 23 METs h/week of moderate-to-vigorous intensity physical activity was significantly and positively associated with the number of supermarkets/convenience stores in the neighborhood in both age groups. In addition, meeting the desired daily step count outlined in the Japanese National Health Promotion guidelines was positively related to the number of postal offices/banks for people aged over 65 years.Conclusion The results of this study suggest that a sufficient number of neighborhood facilities (i.e., stores, banks, and postal offices) is closely associated with the promotion of physical activity.

Objectives To examine the prevalence of health consciousness regarding "Health Japan 21" (2nd edition) among the Japanese population, we conducted a telephone survey of a sample extracted randomly from the whole nation in 2013 and 2014.Methods We extracted 1800 men and women with 150 persons for each gender and 10-year age group (6 age groups ranging from 20 years to 70 years and older) using Random Digital Dialing sampling. Each participant was asked about 1) recognition of the following items: "Health Japan 21," "healthy life expectancy," "metabolic syndrome (MetS)," "chronic obstructive pulmonary disease (COPD)," "locomotive syndrome," "Active Guide," "WHO Framework Convention on Tobacco Control," and "Smart Life Project" and 2) health consciousness toward the following: "health examination taken within the past one year," "smoking status," and "the amount of vegetables considered desirable to consume per day for health." We performed simple tabulation of the collected answers and cross-tabulation by sex and age groups, respectively. For each question about recognition, we categorized "I know the name and meaning" and "I know the name but not the meaning" as "awareness." We compared data between 2013 and 2014, sexes, and age groups, using chi-squared test.Results In 2013, the top 5 items with high awareness were "MetS" (96.2%), "COPD" (51.1%), "healthy life expectancy" (34.2%), "locomotive syndrome" (30.2%), and "WHO Framework Convention on Tobacco Control" (28.0%). Moreover, awareness of "healthy life expectancy," "locomotive syndrome," and "Active Guide" were significantly higher in 2014 than in 2013. Meanwhile, the proportion of participants who correctly chose "350 grams" as "the desirable amount of vegetables to consume per day" was 41.6% in 2013 and became significantly higher at 50.1% in 2014. In 2013, awareness of "healthy life expectancy," "COPD," and "locomotive syndrome" and the proportion of correct answers for "the desirable amount of vegetables to consume per day" were significantly higher among women than among men. In 2013, there were significant differences among age groups in awareness of "MetS," "COPD," "healthy life expectancy," and "locomotive syndrome" and the proportion of correct answers for "the desirable amount of vegetables to consume per day."Conclusion Awareness of "healthy life expectancy," "locomotive syndrome," and health consciousness of "the desirable amount of vegetables to consume per day" were significantly higher in 2014 than in 2013. There were discrepancies on respective items among both sexes and age groups. Therefore, interventions for groups with lower awareness or health consciousness may be required.

BACKGROUND: In Japan, the incidence of kidney stones has increased markedly in recent decades. Major causes of kidney stones remain unclear, and limited data are available on the relationship between overweight/obesity and the incidence of kidney stones. We therefore evaluated body mass index (BMI) and the incidence of kidney stones in Japanese men. METHODS: Of the workers at a gas company, 5984 males aged 20-40 years underwent a medical examination in 1985 (baseline). This study includes 4074 of the men, who were free of kidney stones at baseline and underwent a second medical examination performed between April 2004 and March 2005. BMI was calculated from measured height and weight in 1985, and men were categorized into tertiles. The development of kidney stones during follow-up was based on self-reports from questionnaires at the second medical examination. RESULTS: The average duration of follow-up was 19 years, with 258 participants developing kidney stones during this period. Using the lowest BMI (1st tertile) group as a reference, the hazard ratios (95% confidence intervals [CIs]) for the 2nd and 3rd BMI tertiles were: 1.26 (95% CI, 0.92-1.73) and 1.44 (95% CI, 1.06-1.96), respectively (P for trend = 0.019). After additionally adjusting for potential confounders, such as age, systolic blood pressure, cardiorespiratory fitness, cigarette smoking, and alcohol consumption, the hazard ratios were 1.28 (95% CI, 0.93-1.76) and 1.41 (95% CI, 1.02-1.97), respectively (P for trend = 0.041). CONCLUSIONS: These results suggest that increased BMI is a risk factor for kidney stones in Japanese men.

There are strong genetic components to cardiorespiratory fitness and its response to exercise training. It would be useful to understand the differences in the genomic profile of highly trained endurance athletes of world class caliber and sedentary controls. An international consortium (GAMES) was established in order to compare elite endurance athletes and ethnicity-matched controls in a case-control study design. Genome-wide association studies were undertaken on two cohorts of elite endurance athletes and controls (GENATHLETE and Japanese endurance runners), from which a panel of 45 promising markers was identified. These markers were tested for replication in seven additional cohorts of endurance athletes and controls: from Australia, Ethiopia, Japan, Kenya, Poland, Russia and Spain. The study is based on a total of 1520 endurance athletes (835 who took part in endurance events in World Championships and/or Olympic Games) and 2760 controls. We hypothesized that world-class athletes are likely to be characterized by an even higher concentration of endurance performance alleles and we performed separate analyses on this subsample. The meta-analysis of all available studies revealed one statistically significant marker (rs558129 at GALNTL6 locus, p = 0.0002), even after correcting for multiple testing. As shown by the low heterogeneity index (I-2 = 0), all eight cohorts showed the same direction of association with rs558129, even though p-values varied across the individual studies. In summary, this study did not identify a panel of genomic variants common to these elite endurance athlete groups. Since GAMES was underpowered to identify alleles with small effect sizes, some of the suggestive leads identified should be explored in expanded comparisons of world-class endurance athletes and sedentary controls and in tightly controlled exercise training studies. Such studies have the potential to illuminate the biology not only of world class endurance performance but also of compromised cardiac functions and cardiometabolic diseases.

Background: Physical inactivity is a health issue that often occurs after serious disaster. Social factors, which can be disrupted by disaster, are important determinants of physical activity levels in everyday living. This study was designed to confirm the association between social factors and physical activity among elderly survivors of the Great East Japan Earthquake.
Methods: From September 2011 to February 2012, 4316 males and females aged 65 or older participated in a health survey of Great East Japan Earthquake survivors. Multiple logistic regression analyses were performed with the dichotomous dependent variable of physical activity (high versus low) and working status, social network, and place of residence (one's own home versus elsewhere) as independent variables.
Results: Participants who had been displaced from their homes were more likely to have low physical activity (odds ratio [OR], 95 % confidence interval [CI] for men: 1.37, 1.12 to 1.68; for women: 1.30, 1.09 to 1.55). Non-working status was significantly associated with low physical activity (men: 2.03, 1.65 to 2.49; women: 1.94, 1.60 to 2.34). Detriments to the social network were significantly associated with low physical activity (men: 1.71, 1.41 to 2.08; women: 1.79, 1.51 to 2.13).
Conclusion: Place of residence and social factors were associated with physical activity levels in elderly survivors of the Great East Japan Earthquake. The findings suggest a need for improvement of social factors to encourage increases in physical activity for elderly persons after disaster.

Aim: The present study investigated whether a slow movement protocol can be applied to resistance training using bodyweight. In addition, the intervention program combined plyometric exercise with resistance exercise to improve physical function overall.
Methods: A total of 39 active elderly adults participated in a 16-week intervention. The program consisted of five resistance exercises and four plyometric exercises using their own bodyweight with a single set for each exercise. Participants were assigned to one of two experimental groups. One group carried out resistance exercise with slow movement and tonic force generation (3-s concentric, 3-s eccentric and 1-s isometric actions with no rest between each repetition). The other group as a movement comparison followed the same regimen, but at normal speed (1-s eccentric and 1-s concentric actions with 1-s rest between each repetition). Muscle size, strength and physical function were measured before and after the intervention period.
Results: After the intervention, strengths of upper and lower limbs, and maximum leg extensor power were significantly improved in both groups. Muscle size did not change in either group. There were no significant differences in any of the parameters between groups.
Conclusions: The intervention program using only own bodyweight that comprised resistance exercise with slow movement and plyometric exercise can improve physical function in the elderly, even with single sets for each exercise. However, there was no enhanced muscle hypertrophic effect. Further attempts, such as increasing performing multiple sets, would be required to induce muscle hypertrophy.

© 2015, Center for Academic Publications Japan. All rights reserved. Prospective cohort studies have shown that people with a larger amount of physical activity (PA) and exercise have lower risks of non-communicable diseases (NCDs). In Japan, the Ministry of Health, Labour and Welfare published in March 2013 the “Active-Guide,” i.e. the Japanese official PA guidelines for health promotion. In this document, the most important message is “+10,” standing for “add 10 min of MVPA per day.” The establishment of the “+10” recommendation is supported by strong scientific evidence. Firstly, a meta-analysis including 26 cohort studies indicated that an increment of 10 min of moderate-to-vigorous PA per day can result in a 3.2% reduction of the average relative risk of NCDs, dementia, joint-musculoskeletal impairment, and mortality. Secondly, the National Health and Nutrition Survey (Japan, 2010) reported that 60.8% of the Japanese population is inclined to add the equivalent of 10 min of PA in their daily life. In line with these results, the “+10” recommendation is viewed as feasible and efficient for the Japanese population. To our knowledge, this implementation of an additional low-dose PA recommendation in a governmental health promotion policy is a world first. We hope that the Japanese PA policy will inspire other national and international public health agencies.

Werner syndrome is a rare autosomal recessive disorder caused by mutations in the human WRN gene and characterized by the early onset of normal aging symptoms. Given that patients with this disease exhibit osteoporosis, the present study aimed to determine whether the WRN gene contributes to the etiology of osteoporosis. A genetic association study of eight non-synonymous polymorphisms in the WRN gene and the incidence of femoral fracture was undertaken in 1,632 consecutive Japanese autopsies in which 140 patients had experienced the fracture during their lifetime. The results were validated in 251 unrelated postmenopausal Japanese women with osteoporosis and 269 non-institutionalized, community-dwelling Japanese adults. A statistically significant association was observed between rs2230009 (c.340G &gt; A)-which results in a Val to Ile substitution-and fracture risk; the incidence of femoral fracture increased dose-dependently with the number of A alleles (p = 0.0120). Femoral neck bone and whole bone densities were lower among postmenopausal women with osteoporosis and community-dwelling adults, respectively, if they were of the AG instead of the GG genotype. The results suggest that Japanese subjects bearing at least one A allele of rs2230009 of the WRN gene are at a significantly higher risk of femoral fracture, possibly due to decreased bone density.

AimTo examine the relationship between calf circumference and muscle mass, and to evaluate the suitability of calf circumference as a surrogate marker of muscle mass for the diagnosis of sarcopenia among middle-aged and older Japanese men and women.
MethodsA total of 526 adults aged 40-89 years participated in the present cross-sectional study. The maximum calf circumference was measured in a standing position. Appendicular skeletal muscle mass was measured using dual-energy X-ray absorptiometry, and the skeletal muscle index was calculated as appendicular skeletal muscle mass divided by the square of the height (kg/m(2)). The cut-off values for sarcopenia were defined as a skeletal muscle index of less than -2 standard deviations of the mean value for Japanese young adults, as defined previously.
ResultsCalf circumference was positively correlated with appendicular skeletal muscle (r=0.81 in men, r=0.73 in women) and skeletal muscle index (r=0.80 in men, r=0.69 in women). In receiver operating characteristic analysis, the optimal calf circumference cut-off values for predicting sarcopenia were 34cm (sensitivity 88%, specificity 91%) in men and 33cm (sensitivity 76%, specificity 73%) in women.
ConclusionsCalf circumference was positively correlated with appendicular skeletal muscle mass and skeletal muscle index, and could be used as a surrogate marker of muscle mass for diagnosing sarcopenia. The suggested cut-off values of calf circumference for predicting low muscle mass are &lt;34cm in men and &lt;33cm in women. Geriatr Gerontol Int 2015; 15: 969-976.

Although palmitoleic acid (C16:1) is associated with arrhythmias, and increases in an age-dependent matter, the effects of L-carnitine, which is essential for the transport of long-chain fatty acids into the mitochondria, are unclear. It has been postulated that L-carnitine may attenuate palmitate (C16:0)induced mitochondrial dysfunction and the apoptosis of cardiomyocytes. The aim of this study was to elucidate the activity of L-carnitine in the prevention of the palmitoleic acid-induced mitochondrial membrane permeability transition and cytochrome c release using isolated cardiac mitochondria from rats. Palmitoleoyl-CoA-induced mitochondrial respiration was not accelerated by L-carnitine treatment, and this respiration was slightly inhibited by oligomycin, which is an inhibitor of ATP synthase. Despite pretreatment with L-carnitine, the mitochondrial membrane potential decreased and mitochondrial swelling was induced by palmitoleoyl-CoA. In the presence of a combination of L-carnitine and tiron, a free radical scavenger, there was attenuated mitochondrial swelling and cytochrome c release following palmitoleoyl-CoA treatment. We concluded that palmitoleic acid, but not palmitate, induces the cardiac mitochondrial membrane permeability transition despite the presence of L-carnitine. (C) 2015 Elsevier Inc. All rights reserved.

BackgroundThe United States and Japan have similar standards of living, healthcare systems, and industrializations but exhibit markedly divergent life expectancies both at birth and at later ages (50 or 65years old). Arterial stiffness has been widely regarded as a barometer of biological or physiological aging and could provide insight into the inter-country differences.
ObjectivesTo determine whether the increases in arterial stiffness across the adult age range are greater in U.S. than Japanese adults.
DesignCross-sectional analyses.
SettingLaboratory-based study.
ParticipantsHealthy, nonsmoking Japanese (n=400) and U.S. (n=400) adults without cardiovascular and other chronic diseases.
MeasurementsIndices of arterial stiffness, including carotid-femoral (cfPWV) and brachial-ankle pulse wave velocity (baPWV) were measured, along with a variety of ancillary measures. The recruitment method, measurement technique, and protocol were standardized and identical between U.S. and Japanese facilities.
ResultscfPWV and baPWV increased progressively with advancing age in all subgroups (stratified according to sex and country). The rates of age-related increases in arterial stiffness were not different between U.S. and Japanese men, but age-associated increases in cfPWV were significantly greater in U.S. than Japanese women, widening the intercountry differences at older age ranges.
ConclusionJapanese women had smaller increases in central arterial stiffness with advancing age than U.S. women.

Background: Promotion of physical activity (PA) is a key strategy to prevent non-communicable diseases. However, evidence on the effectiveness of community-wide interventions (CWIs) for promoting PA is limited.
Purpose: To evaluate the effectiveness of a 3-year CWI for promoting PA in middle-aged and older adults compared with usual public health services. This study is an extension to an original 1-year investigation study.
Design: Cluster randomized controlled trial with community as unit of randomization and individual as unit of analysis.
Setting/participants: 12 communities in Unnan, Japan were randomly allocated to the intervention (9) or the control (3). Additionally intervention communities were randomly allocated to aerobic activity promotion (Group A), flexibility and muscle-strengthening activities promotion (Group FM), or aerobic, flexibility, and muscle-strengthening activities promotion (Group AFM), each consisting of three communities. Randomly-sampled 4414 residents aged 40 to 79 years responded to the baseline survey (74 %), and were analyzed in 2013-2014.
Intervention: A 3-year CWI based on social marketing, to promote PA from 2009 to 2012.
Main outcome measures: The primary outcome was a change in regular aerobic, flexibility, and/or musclestrengthening activities, defined by (1) engaging in 150 mins/week or more of walking, (2) engaging in daily flexibility activity, or (3) engaging 2 or more days/week in muscle-strengthening activities, evaluated at the individual level. Secondary outcomes were changes in specific types of PA and musculoskeletal pain. Outcomes were measured at baseline and at 1 and 3 years (2009, 2010, and 2012).
Results: The CWI did not significantly increase the proportion of adults who reached recommended levels of aerobic, flexibility, and/or muscle-strengthening activities (adjusted change difference = 1.6 % [95 % CI: -3.5, 6.6]). In the subgroup analysis, compared to the controls, adults doing flexibility activity daily significantly increased in Group FM (6.3 % [95 % CI: 1.9, 10.7]). In Group A and AFM for PA outcomes and in all groups for pain outcomes, there was no significant change compared to controls.
Conclusions: The CWI did not achieve significant increase in the proportion of adults who reached recommended PA levels. However, it might be effective in promoting flexibility activity in middle-aged and older Japanese.

サルコペニアや認知症、2型糖尿病や高血圧のような老年疾患の予防・改善に、身体活動や運動が有効であることはよく知られている。最近では、これら疾患に対する高齢者を対象としたランダム化比較試験や食事・栄養との併用効果に関する研究が報告され、身体活動・運動は高齢者の健康寿命の延伸を考えるうえで欠かすことができないものとなっている。今後、高齢化により老年疾患の罹患者数は増加することが予想され、身体活動・運動の役割はさらに大きくなると考えられる。これまでは有酸素運動やレジスタンス運動といった、いわゆる"運動"により疾病予防・改善をめざすことが推奨されていたが、最近では日々身体を動かす場面を増やすこと、つまり日常生活での"身体活動"を増加させることの重要性が明らかとなってきた。高齢者にとって、どのような身体活動・運動が取り組みやすく、かつ効果的であるのかを今後も考えていく必要がある。(著者抄録)

There are several gene variants that are candidates to influence functional capacity in long-lived individuals. As such, their potential association with exceptional longevity (EL, i.e., reaching 100+ years) deserves analysis. Among them are rs7832552 in the thyrotropin-releasing hormone receptor (TRHR) gene, rs1800795 in the interleukin-6 (IL6) gene and rs6552828 in the coenzyme A synthetase long-chain 1 (ACSL1) gene. To gain insight into their functionality (which is yet unknown), here we determined for the first time luciferase gene reporter activity at the muscle tissue level in rs7832552 and rs6552828. We then compared allele/genotype frequencies of the 3 abovementioned variants among centenarians [n = 138, age range 100-111 years (114 women)] and healthy controls [n = 334, 20-50 years (141 women)] of the same ethnic and geographic origin (Spain). We also studied healthy centenarians [n = 79, 100-104 years (40 women)] and controls [n = 316, 27-81 years (156 women)] from Italy, and centenarians [n = 742, 100-116 years (623 women)] and healthy controls [n = 499, 23-59 years (356 women)] from Japan. The THRH rs7832552 T-allele and ACSL1 rs6552828 A-allele up-regulated luciferase activity compared to the C and G-allele, respectively (P = 0.001). Yet we found no significant association of EL with rs7832552, rs1800795 or rs6552828 in any of the 3 cohorts. Further research is needed with larger cohorts of centenarians of different origin as well as with younger old people.

This study aimed to compare the accuracy for predicting body composition using single-frequent segmental bioelectrical impedance analysis (BIA) between pre- and postmenopausal women. A total f 559 Japanese women aged 30-88 yr were divided into 4 groups by questionnaire: natural menopause, pathological menopause, regular menstruation, or irregular menstruation. The measurement values by dual-energy X-ray absorptiometry were used as a reference of the body composition. In terms of the results, regardless of the menopausal status, BIA slightly but significantly overestimated the percentage of body fat (standard error of estimate: 5.3%-6.7%) and the leg lean soft tissue mass (LSTM; 5.1%-6.1%), and underestimated the LSTM in the whole body (6.2%-7.6%) and arm (2.8%-3.7%). The absolute values of the predictive error for leg LSTM were significantly higher in postmenopausal groups than in the premenopausal ones. The corresponding values for the whole body and arm LSTM, and the percentage of body fat were higher in premenopausal groups than in postmenopausal ones. In conclusion, the predictive accuracy of BIA for postmenopausal women is not inferior to that for premenopausal ones, unless we target the leg LSTM.

Background: Extended sitting time at work is viewed as a crucial public health issue. Encouraging workers to stand during their office hours via the installation of standing desks maybe one effective option to combat this. Here, we investigate whether the installation of high desks in the workplace can induce positive changes in the amount of physical activity (PA) and thereby lead to subsequent improvements in anthropometric parameters.
Methods: Thirty-two white-collar workers (22 men and 10 women, mean age 44.2) were randomly divided into two groups. A randomised crossover trial was performed for 13 weeks. During the experimental period, subjects completed their office work in a standing position using stationary high desks (standing work, SW) for 10 hours per week or more (SW period). The subjects were asked to maintain their normal sitting working habits during the control period (CONT period). The primary outcome was PA, which was assessed objectively using a triaxial accelerometer during weekdays and weekends. The secondary outcomes were anthropometric measurements. For each group and each parameter, the mean values during each period were recorded and were compared by paired t test.
Results: The daily total PA (10.2 +/- 2.4 vs. 9.7 +/- 2.3 METs . h/day, P = 0.043), MVPA (4.2 +/- 2.2 vs. 3.7 +/- 1.8 METs . h/day, P = 0.025), time spent in moderate PA (58.2 +/- 20.7 vs. 53.4 +/- 17.0 min/day, P = 0.019) and time spent in MVPA (62.8 +/- 25.1 vs. 57.0 +/- 20.3 min/day, P = 0.019) were significantly higher during the SW period compared to the CONT period. A weekdays verses weekends subanalysis revealed that these parameters were significantly higher during the SW period compared to the CONT period during weekdays only. No significant differences were noted before and after SW periods for most of the anthropometric measures, except waist circumference (83.7 +/- 7.9 vs. 83.0 +/- 7.9 cm, respectively, P = 0.007).
Conclusions: Standing work, via the installation of high desks, significantly increases moderate to vigorous physical activity, especially on weekdays.

子どもの身体活動を促進するうえで,現存するエビデンスをまとめ,国際比較を実施し,エビデンスに基づいた身体活動や健康面の施策を促すための情報を研究者だけでなく教員,指導者,政策立案者および一般大衆が共有することは,極めて重要なことと考えられる。"Active Healthy Kids ReportCard"は,各国の子どもの身体活動の現状および,身体活動に影響する要因を示すものとして,主に9つの指標によって構造化されている。2005年に,初版の"Active Healthy Kids Canada Report Card"が発表されて以来,Active Healthy Kids Global Alliance(www.activehealthykids.org)を形成するさまざまな国民所得水準の15か国において,"Active Healthy Kids Report Card"が報告されている。きたる2016年の第6回The International Congress on Physical Activity and Public Healthバンコク大会に向け,更に地理的および経済的に異なる国を加えた40か国を超える国が参加する予定である。"Active Healthy Kids JAPAN Report Card"についても,現在ワーキンググループで検討中である。本稿はこれまで報告されている15か国の"Active Healthy Kids Report Card"および国際比較の結果について概説した。(著者抄録)

Background: The independent and combined associations of muscle strength and obesity on the prevalence of type 2 diabetes in Japanese men remain unclear.
Methods: Hand grip strength was cross-sectionally evaluated between 2011 and 2013 to assess muscle strength in 5039 male workers aged 40 to 64 years. Weight and height were measured, and overweight/obesity was defined as a body mass index &gt;= 25 kg/m(2). The prevalence of type 2 diabetes, defined as fasting plasma glucose &gt;= 126 mg/dL and/or hemoglobin A1c &gt;= 6.5% and/or self-reported physician-diagnosed diabetes, was evaluated. Odds ratios (OR) and 95% confidence intervals (95% CI) for the prevalence of type 2 diabetes were obtained using a logistic regression model.
Results: In total, 611 participants had type 2 diabetes, and 1763 participants were overweight/obese. After adjustment for covariates, we found an inverse association between muscle strength and the prevalence of type 2 diabetes (P for trend &lt;0.01). In addition, when the analyses were stratified by obesity status, the multivariable-adjusted OR per 2-standard-deviation increase in muscle strength was 0.64 (95% CI, 0.49-0.83) in the overweight/obese group, compared to a weaker relationship in the normal-weight group (OR 0.79 per 2-standard-deviation increase; 95% CI, 0.60-1.06).
Conclusions: Dynapenia, an age-related decrease in muscle strength, is associated with increased prevalence of type 2 diabetes, and this relationship is stronger in overweight/obese middle-aged Japanese men than in normal-weight men.

There has been a considerable increase in the number of studies reporting associations between DNA sequence variation in specific genes and metabolic syndrome (MetS). A low level of cardiorespiratory fitness is also a strong determining factor in the development of MetS. This cross-sectional study was performed to investigate the influence of the interaction between obesity genes and cardiorespiratory fitness on the risk of MetS. Healthy Japanese men (n = 287) participated in this study. All subjects were divided into four groups, fitness level (high and low fitness groups), and age (younger, age &lt
40 years and middle-aged/older, age ≥ 40 years). The peroxisome proliferator-activated receptor gamma 2 (PPARγ2), the uncoupling protein-2 (UCP2), and the fatty acid binding protein 2 (FABP2) genotypes were analyzed by using real-time polymerase chain reaction (PCR) with Taq-Man probes. Two-way analysis of covariance (ANCOVA) with adjustment for age as a covariate indicated that fitness, the CC genotype of C1431T in the PPARγ2, and the ValVal genotype of Ala55Val in the UCP2 genes interacted to produce a significant effect on MetS risk in Japanese adult men. We concluded that the CC genotype of C1431T in the PPARγ2 and the ValVal genotype of Ala55Val in the UCP2 genes together with low cardiorespiratory fitness may increase the risk of MetS in younger men (age &lt
40 years), even with adjustment for age.

Irisin might play an important role in reducing the risk of obesity, insulin resistance, or several related diseases, and high irisin levels may contribute to successful aging. Thus, the irisin precursor (FNDC5) gene is a candidate to influence exceptional longevity (EL), i.e., being a centenarian. It has been recently shown that two single-nucleotide polymorphisms (SNPs) in the FNDC5 gene, rs16835198 and rs726344, are associated with in vivo insulin sensitivity in adults. We determined luciferase gene reporter activity in the two above-mentioned SNPs and studied genotype distributions among centenarians (n=175, 144 women) and healthy controls (n= 347, 142 women) from Spain. We also studied an Italian [79 healthy centenarians (40 women) and 316 healthy controls (156 women)] and a Japanese cohort [742 centenarians (623 women) and 499 healthy controls (356 women)]. The rs726344 SNP had functional significance, as shown by differences in luciferase activity between the constructs of this SNP (all P &lt;= 0.05), with the variant A-allele having higher luciferase activity compared with the G-allele (P=0.04). For the rs16835198 SNP, the variant T-allele tended to show higher luciferase activity compared with the G-allele (P=0.07). However, we found no differences between genotype/allele frequencies of the two SNPs in centenarians versus controls in any cohort, and no significant association (using logistic regression adjusted by sex) between the two SNPs and EL. Further research is needed with different cohorts as well as with additional variants in the FNDC5 gene or in other genes involved in irisin signaling.

Background: Both little and excessive physical activity (PA) may relate to chronic musculoskeletal pain. The primary objective of this study was to characterize the relationship of PA levels with chronic low back pain (CLBP) and chronic knee pain (CKP).
Methods: We evaluated 4559 adults aged 40-79 years in a community-based cross-sectional survey conducted in 2009 in Shimane, Japan. We used self-administered questionnaires to assess sociodemographics and health status: PA was assessed by the International Physical Activity Questionnaire, and CLBP and CKP were assessed by a modified version of the Knee Pain Screening Tool. We examined relationships of PA with prevalence of CLBP and CKP using Poisson regression, controlling for potential confounders.
Results: CLBP and CKP were both prevalent (14.1% and 10.7%, respectively) and associated with history of injury, medication use, and consultation with physicians. PA was not significantly related to CLBP or CKP (P &gt; 0.05) before or after adjustment for potential confounders. For example, compared with adults reporting moderate PA (8.25-23.0 MET-hours/week), prevalence ratios for CKP adjusted for sex, age, education years, self-rated health, depressive symptom, smoking, chronic disease history, and body-mass index were 1.12 (95% confidential interval [CI] 0.84-1.50) among those with the lowest PA and 1.26 (95% CI 0.93-1.70) among those with the highest PA (P quadratic = 0.08). The prevalence ratios were further attenuated toward the null after additional adjustment for history of injury, medication use, and consultation (P quadratic = 0.17).
Conclusions: This cross-sectional study showed that there were no significant linear or quadratic relationships of self-reported PA with CLBP and CKP. Future longitudinal study with objective measurements is needed.

目的 国民健康・栄養調査における歩数の平均値は、健康日本21における身体活動・運動分野の評価に用いられるとともに、国民の身体活動や運動に関する代表的なデータとして利用されている。本研究は、国民健康・栄養調査における歩数のデータの特性を明らかにすることを目的とした。方法 2008年から2010年の計3年分の国民健康・栄養調査のデータのうち、1日の歩数および歩数計装着状況のデータがある21,914人を対象として分析を行った。栄養摂取状況調査票の身体状況調査項目における歩数計の装着状況として終日歩数計を装着したと回答した群を「終日装着群」とし、「非終日装着群」との平均値、中央値、外れ値、度数分布の比較を行った。結果 2008年、2009年、2010年における「非終日装着群」の割合は、すべての測定年において全体の約8%であった。各年の平均歩数は、「終日装着群」が「非終日装着群」より1,076から1,472歩高い値を示していた。また、両群ともに外れ値が存在し、度数分布については両群とも歩数の多い方に裾を引いていることが確認された。それに伴い、平均値は中央値よりも約600歩多い値を示していた。結論 国民健康・栄養調査の歩数のデータには歩数計を終日装着していない約8%の者が含まれ、データが正規分布を示さないことから、国民の身体活動や運動に関する代表値として利用する際にはデータの特性を考慮する必要があると考えられる。(著者抄録)

Focal adhesion is critical for cell survival. The focal adhesion kinase (FAK, or PTK2) is an important component of the human interactome and thus is a potential longevity-related protein. Here we studied the association between two PTK2 gene single-nucleotide polymorphisms (SNPs) (rs7843014, rs7460) and exceptional longevity (EL). In addition to gaining insight into their functionality by determining luciferase gene reporter activity, we studied the genotype/allele frequency of these two SNPs among three different cohorts: (1) Spanish centenarians (n=175, 100-111 years, 144 women) and healthy controls (n=355, 20-50 years, 284 women); (2) Italian centenarians (n=79, 100-104 years, 40 women) and controls (n=316, 29-50 years, 156 women); and (3) Japanese centenarians (n=742, 100-116 years, 623 women) and healthy controls (n=499, 23-59 years, 356 women). Both SNPs had functional significance, with the A allele up-regulating luciferase activity compared to the other allele (rs7460 T allele and rs7843014 C allele, respectively). The A allele of both SNPs was negatively associated with EL in the Spanish cohort (rs7460, odds ratio [OR] adjusted by sex=0.40, 95% confidence intervals [CI] 0.3, 0.6, p&lt;0.001); rs7843014, OR=0.37, 95% CI 0.3, 0.5, p&lt;0.001). The OR of being a centenarian if having the rs7460-TT genotype was 6.68 (95% CI 4.1, 10.8, p&lt;0.001). The rs7843014 CC genotype was also positively associated with EL (OR=7.58, 95% CI 4.6, 12.3, p&lt;0.001]. No association was, however, found for the Italian or Japanese cohorts. Thus, two genotypes of the FAK gene, rs7460 TT and rs7843014 CC, are possibly associated with lower gene expression and might favor the likelihood of reaching EL in the Spanish population. Further research is needed to unveil the mechanisms by which FAK expression could perhaps influence the rate of aging.

The largest percentage of mortality from tobacco smoking is cardiovascular-related. It is not known whether regular participation in exercise mitigates the adverse influence of smoking on vasculature. Accordingly, the authors determined whether regular aerobic exercise is associated with reduced arterial stiffness in men who smoke cigarettes. Using a cross-sectional study design, 78 young men were studied, including sedentary nonsmokers (n=20), sedentary smokers (n=12), physically active nonsmokers (n=21), and physically active smokers (n=25). Arterial stiffness was assessed by brachial-ankle pulse wave velocity (baPWV). There were no group differences in height, body fat, and systolic and diastolic blood pressure. As expected, both physically active groups demonstrated greater maximal oxygen consumption and lower heart rate at rest than their sedentary peers. The sedentary smokers demonstrated greater baPWV than the sedentary nonsmokers (11.8 +/- 1 m/s vs 10.6 +/- 1 m/s, P=.036). baPWV values were not different between the physically active nonsmokers and the physically active smokers (10.8 +/- 1 m/s vs 10.7 +/- 1 m/s). Chronic smoking is associated with arterial stiffening in sedentary men but a significant smoking-induced increase in arterial stiffness was not observed in physically active adults. These results are consistent with the idea that regular participation in physical activity may mitigate the adverse effects of smoking on the vasculature. (C) 2014 Wiley Periodicals, Inc.

Purpose: To investigate the link between peak oxygen uptake and regional body composition by dual energy X-ray absorptiometry (DEXA) in Japanese subjects.
Methods: A total of 93 men (42.2 +/- 12.3 years old) and 106 women (43.5 +/- 12.3 years old) were enrolled in this cross-sectional investigation study. Peak oxygen uptake was measured by the breath-by-breath method. Regional body composition i.e., body fat mass, lean body mass, and body fat percentage was evaluated using DEXA. In addition, metabolic risk parameters were also evaluated.
Results: Peak oxygen uptake was 37.6 +/- 8.7 mL/kg/min in men and 31.1 +/- 6.4 mL/kg/min in women, and decreased with age in both genders. Peak oxygen uptake was significantly correlated with total body fat percentage (men: r = -0.684, p &lt; 0.0001; women: r = -0.681, p &lt; 0.0001). These associations remained even after adjusting for age and total lean body mass. However, peak work rate was positively and significantly correlated with leg lean body mass.
Conclusion: Peak oxygen uptake was closely correlated with total body fat percentage in both genders. Aerobic exercise as well as leg resistance training might be useful for improving peak oxygen uptake in Japanese subjects. Copyright (C) 2014, Shanghai University of Sport. Production and hosting by Elsevier B.V. All rights reserved.

The aim of this study was to evaluate the link between circulating leptin levels and physical activity and/or physical fitness in apparently healthy Japanese.
A total of 85 men and 111 women who were not taking any medication were enrolled in this cross-sectional study. Circulating leptin levels, physical activity measured by tri-axial accelerometers and peak oxygen uptake were evaluated. We also assessed anthropometric data, blood pressure, blood examinations and energy intake.
Circulating leptin levels were 3.2 +/- A 2.3 ng/mL in men and 5.9 +/- A 3.8 ng/mL in women. Circulating leptin levels were significantly and positively correlated with body weight, body mass index, abdominal circumference, insulin and the homeostasis model assessment index, and significantly and negatively correlated with peak oxygen uptake in both sexes. Stepwise multiple regression showed that peak oxygen uptake in men and physical activity evaluated by in women were determinant factors for circulating leptin levels after adjusting for confounding factors.

BACKGROUND: The Wii Fit series (Nintendo Inc., Japan) provides active video games (AVGs) to help adults to maintain a sufficient level of daily physical activity (PA). The second generation of home AVG consoles is now emerging with new game modalities (including a portable mini screen in the case of the new Wii U). The present study was performed to investigate the intensity and enjoyment of Wii Fit U games among adults. FINDINGS: Metabolic equivalent (METs, i.e., intensity) of the Wii Fit U activities were evaluated using metabolic chambers in 16 sedentary adults (8 women and 8 men). A short version of the physical activity enjoyment scale was completed for each activity. Wii Fit U activities were distributed over a range from 2.2  ±  0.4 METs (Hula dance) to 4.7  ±  1.2 (Hip-hop dance). Seven activities were classified as light-intensity PA (<3 METs) and 11 activities as moderate-intensity PA (3 - 6 METs). The new portable mini screen game modality does not induce higher METs. Men exercised at higher intensities than women. There was no correlation between enjoyment and MET values in women or men. CONCLUSIONS: More and more moderate-intensity activities are available through video gaming, but the average intensity (3.2  ±  0.6) is still low. Users should be aware that AVGs alone cannot fulfill the recommendations for PA, and the video games industry still must innovate further to enhance gaming intensity and make the tool more attractive to health and fitness professionals.

The aim of this study was to investigate the link between circulating adiponectin levels and peak oxygen uptake and/or physical activity in Japanese.
A total of 528 subjects (188 men and 340 women) were enrolled in this cross-sectional study. Circulating adiponectin levels, physical activity measured by tri-axial accelerometers, peak oxygen uptake and metabolic risk parameters were evaluated. We also assessed anthropometric factors, blood pressure, blood examinations and energy intake.
Circulating adiponectin levels were 6.7 +/- A 3.0 mu g/mL in men and 11.0 +/- A 4.9 mu g/mL in women. Circulating adiponectin levels were positively correlated with physical fitness after adjusting for age, physical activity evaluated by I pound [metabolic equivalents x h per week (METs h/w)], cigarette smoking habit and energy intake in both sexes. However, these associations were attenuated further after adjusting for body mass index including other confounding factors, especially in men. However, circulating adiponectin levels were not associated with physical activity in either sex.
Circulating adiponectin levels were associated with peak oxygen uptake rather than physical activity.

beta 3-Adrenergic receptor (ADRB3) Trp64Arg polymorphism is associated with atherogenic risk factors that include weight gain, insulin resistance, and diabetes. Habitual exercise brings higher cardiorespiratory fitness and results in the amelioration of atherosclerotic risk factors. However, the effects of cardiorespiratory fitness level and ADRB3 Trp64Arg polymorphism on the risk of cardiovascular disease remain unclear. A cross-sectional investigation of 877 Japanese men and women (18-75 years old) was performed to clarify the effects of cardiorespiratory fitness on the relationship between ADRB3 Trp64Arg polymorphism and risk of cardiovascular disease.
Common carotid intima-media thickness (ccIMT) and blood lipid profiles were assessed as surrogate markers of atherosclerosis. We measured peak oxygen uptake (O-2peak) during incremental cycle ergometer exercise testing. Subjects were divided into groups with high (High-Fit) and low (Low-Fit) levels of cardiorespiratory fitness based on the median value of O-2peak for sex and decade.
Levels of body fat, triglycerides, and plasma glucose were lower and high-density lipoprotein cholesterol levels and O-2peak were higher in High-Fit subjects than Low-Fit subjects. ADRB3 Trp64Arg polymorphism did not significantly affect ccIMT or blood lipid profiles. In Low-Fit subjects, ccIMT was higher in individuals with the Arg/Arg genotype compared to the Trp/Trp and Trp/Arg genotypes (each P &lt; 0.0001); however, ADRB3 polymorphism had no effect in High-Fit subjects.
Higher levels of cardiorespiratory fitness may attenuate the risk of atherosclerosis associated with ADRB3 Trp64Arg polymorphism.

To investigate the link between serum vaspin levels and physical activity and/or physical fitness in Japanese.
A total of 156 subjects (81 men and 75 women) was enrolled in this cross-sectional study. Serum vaspin levels, physical activity by uniaxial accelerometers, peak oxygen uptake, and metabolic risk parameters were evaluated. We also assessed anthropometric and body composition parameters.
Serum vaspin levels were over the level of 10 ng/mL in 15 subjects (9.6 %: Vaspin High group). In Vaspin Low group (&lt; 5 ng/mL: 74 men and 67 women), serum vaspin levels were 0.12 +/- A 0.18 ng/mL in men and 0.39 +/- A 0.70 ng/mL in women. Peak oxygen uptake was significantly and positively correlated with serum vaspin levels even after adjusting for age, physical activity evaluated by I [metabolic pound equivalents x h per week (METsa &lt;...h/w)], BMI, and other confounding factors in men. In turn, physical activity was significantly and positively correlated with serum vaspin levels even after adjusting for confounding factors in women.
Serum vaspin levels were closely associated with physical fitness in men and physical activity in women independent of body composition in this Japanese cohort.

The ApoE gene is associated with the risk of Alzheimer or cardiovascular disease but its influence on exceptional longevity (EL) is uncertain. Our primary purpose was to determine, using a case-control design, if the ApoE gene is associated with EL. We compared ApoE allele/genotype frequencies among the following cohorts: cases (centenarians, most with 1+ major disease condition; n=163, 100-111 years) and healthy controls (n=1039, 20-85 years) from Spain; disease-free cases (centenarians; n=79, 100-104 years) and healthy controls (n=597, age 27-81 years) from Italy; and cases (centenarians and semi-supercentenarians, most with 1+ major disease condition; n=729, 100-116 years) and healthy controls (n=498, 23-59 years) from Japan. Ourmain findings were twofold. First, the epsilon 4-allele was negatively associated with EL in the three cohorts, with the following odds ratio (OR) values (adjusted by sex) having been found: 0.55 (95% confidence interval (CI): 0.33, 0.94), P = 0.030 (Spain); 0.41 (95% CI: 0.18, 0.99), P = 0.05 (Italy); and 0.35 (95% CI: 0.26, 0.57), P &lt; 0.001 (Japan). Second, although no association was found in the Spanish cohort (OR = 1.42 (95% CI: 0.89, 2.26), P = 0.145), the epsilon 2-allele was positively associated with EL in the Italian (OR = 2.14 (95% CI: 1.18, 3.45), P = 0.01) and Japanese subjects (OR = 1.81 (95% CI: 1.25, 2.63), P = 0.002). Notwithstanding the limitations of case-control designs, our data suggest that the ApoE might be a candidate to influence EL. The epsilon 4-allele appears to decrease the likelihood of reaching EL among individuals of different ethnic/geographic origins. An additional, novel finding of our study was that the epsilon 2-allele might favor EL, at least in the Italian and Japanese cohorts. (C) 2014 Elsevier Inc. All rights reserved.

The rs1333049 (G/C) polymorphism located on chromosome 9p21.3 is a candidate to influence extreme longevity owing to its association with age-related diseases, notably coronary artery disease (CAD). We compared allele/genotype distributions of rs1333049 in cases (centenarians) and controls (younger adults, without (healthy) or with CAD) in two independent cohorts: Spanish (centenarians: n = 152, 128 women, 100-111 years; healthy controls: n = 343, 212 women, age &lt; 50 years; CAD controls: n = 98, 32 women, age a parts per thousand currency sign65 years) and Japanese (centenarians: n = 742, 623 women, 100-115 years; healthy controls: n = 920, 511 women, &lt; 60 years; CAD controls: n = 395, 45 women, age a parts per thousand currency sign65 years). The frequency of the "risk" C-allele tended to be lower in Spanish centenarians (47.0 %) than in their healthy (52.9 %, P = 0.088) or CAD controls (55.1 %, P = 0.078), and significant differences were found in genotype distributions (P = 0.034 and P = 0.045), with a higher frequency of the GG genotype in cases than in both healthy and CAD controls as well as a lower proportion of the CG genotype compared with healthy controls. In the Japanese cohort, the main finding was that the frequency of the C-allele did not differ between centenarians (46.4 %) and healthy controls (47.3 %, P = 0.602), but it was significantly lower in the former than in CAD controls (57.2 %, P &lt; 0.001). Although more research is needed, the present and recent pioneer findings (Rejuvenation Res 13:23-26, 2010) suggest that the rs1333049 polymorphism could be among the genetic contributors to exceptional longevity in Southern European populations, albeit this association does not exist in the healthy (CAD-free) Japanese population.

Physical activity (PA) is associated with reductions in the risk of all-cause mortality and in the prevalence of cardiovascular disease and stroke. Nevertheless, a large proportion of the general population may not be sufficiently active. PA level has been reported to be influenced by genetic factors, and we investigated whether Q223R polymorphism in the leptin receptor (LEPR) gene was associated with PA level. A total of 556 Japanese adults aged 24-65 years old participated in this cross-sectional study. The duration and intensity of PA were objectively evaluated by triaxial accelerometry. Q223R polymorphism was determined by the TaqMan method. The distribution of Q223R polymorphism was: QQ 0.7%, QR 22.6%, and RR 76.6%. The relation between the LEPR genotype and PA level was analyzed by ANCOVA with age and sex as covariates in the Q dominant genetic model. There were significant differences between LEPR genotypes and the time spent in light PA or inactive time. The subjects with RR genotype showed significantly shorter time spent in light PA (RR genotype: 559.4 +/- 102.9 min/day, QQ/QR genotype: 579.9 +/- 103.1 min/day) and longer inactive time (RR genotype: 815.5 +/- 107.5 min/day, QQ/QR genotype: 792.3 +/- 107.7 min/day) than the subjects with QQ/QR genotype (P &lt; 0.05). There were no such differences in the time spent in moderate or vigorous PA. These results suggest that the variety of PA level, especially spontaneous PA in humans, is partly caused by diversity in the LEPR gene. (C) 2014 The Authors. Published by Elsevier Inc.

Menaquinone-4 (MK-4) administered at a pharmacological dosage of 45 mg/day has been used for the treatment of osteoporosis in Japan. However, it is not known whether a lower dose of MK-4 supplementation is beneficial for bone health in healthy postmenopausal women. The aim of this study was to examine the long-term effects of 1.5-mg daily supplementation of MK-4 on the various markers of bone turnover and bone mineral density (BMD). The study was performed as a randomized, double-blind, placebo-controlled trial. The participants (aged 50-65 years) were randomly assigned to one of two groups according to the MK-4 dose received: the placebo-control group (n = 24) and the 1.5-mg MK-4 group (n = 24). The baseline concentrations of undercarboxylated osteocalcin (ucOC) were high in both groups (&gt; 5.1 ng/ml). After 6 and 12 months, the serum ucOC concentrations were significantly lower in the MK-4 group than in the control group. In the control group, there was no significant change in serum pentosidine concentrations. However, in the MK-4 group, the concentration of pentosidine at 6 and 12 months was significantly lower than that at baseline. The forearm BMD was significantly lower after 12 months than at 6 months in the control group. However, there was no significant decrease in BMD in the MK-4 group during the study period. These results suggest that low-dose MK-4 supplementation for 6-12 months improved bone quality in the postmenopausal Japanese women by decreasing the serum ucOC and pentosidine concentrations, without any substantial adverse effects.

Purpose Weight retention during the postpartum period is critical for the later development of obesity in women. Traditional physical activity is frequently discontinued because of incompatibility with mothers' agenda (i.e., baby care). In the present study, active video games (AVG) are proposed for postpartum women to improve their body composition. Methods Thirty-four postpartum women (body mass index = 24.5 +/- 3.4 kg center dot m(-2)) were randomized to an AVG group or a control group. Subjects assigned to the AVG group were given a Wii Nintendo console with the game Wii Fit Plus for 40 d. The two groups were tested for weight, body mass index, body fat mass, waist and hip circumferences, and other anthropometric parameters. Physical fitness, energy expenditure, energy intake, and adverse events were also investigated. Results The AVG group lost more weight than the control group (-2.2 +/- 0.9 vs. -0.5 +/- 0.7 kg, P &lt; 0.001). They also exhibited more important reductions of BMI, waist and hip circumferences, and body fat (P &lt; 0.05). During the 40-d period, subjects expended an estimated 4682 +/- 2874 kcal just by playing AVG. Daily energy intake was reduced by 206 +/- 559 kcal. There were significant positive correlations between playing frequency, total playing time, total energy expenditure during the 40-d period, and decrease in daily energy intake respectively, and weight loss (P &lt; 0.05). Playing time data suggested no conflict with baby care activities. Conclusions AVGs could represent an interesting spare physical activity for postpartum women. In the present study, these games promoted physical activity, induced a reduction of energy intake, and subsequently minimized weight retention.

Although intense exercise may induce temporary immune depression, it is unclear whether exercise stimulates tumor necrosis factor-alpha (TNF-α) production in response to flagella protein flagellin (FG), which binds to toll-like receptor 5 (TLR5) and induces the production of pro-inflammatory cytokines. Male C3H/HeN mice were administered FG (1. mg/kg, i.v.) after exhaustive exercise (EX), and the plasma TNF-α concentrations were examined. The production of TNF-α and the TLR5 expression in both RAW264 and Caco2 cells were measured under FG conditions in vitro. Although the plasma TNF-α concentrations were observed to significantly increase in both the EX and non-EX (N-EX) mice (p&lt; 0.01, respectively) following FG injection, the TNF-α levels in the EX mice were significantly higher than those observed in the N-EX mice (p&lt; 0.01). Epinephrine (Ep) treatment accelerated the FG-induced TNF-α production and TLR5 expression on the Caco2, but not RAW264 cells. Interestingly, a high Ep-induced TLR5 expression was observed on the Caco2 cell surface, which was inhibited by an inhibitor of phosphoinositide3-kinase (PI3K), Ly294002, as well as a β-adrenergic blocker, propranolol. In addition, the EX-induced TNF-α production observed in response to FG was also attenuated by pretreatment with propranolol. Our findings suggest that exhaustive exercise upregulates the production of TNF-α in response to FG via a high expression of TLR5 on the intestinal cell surface following the stimulation of β-adrenergic receptors with exercise. © 2014 Elsevier B.V.

Purpose: Weight retention during the postpartum period is critical for the later development of obesity in women. Traditional physical activity is frequently discontinued because of incompatibility with mothers' agenda (i.e., baby care). In the present study, active video games (AVG) are proposed for postpartum women to improve their body composition. Methods: Thirty-four postpartum women (body mass index = 24.5 ± 3.4 kg·m) were randomized to an AVG group or a control group. Subjects assigned to the AVG group were given a Wii Nintendo console with the game Wii Fit Plus for 40 d. The two groups were tested for weight, body mass index, body fat mass, waist and hip circumferences, and other anthropometric parameters. Physical fitness, energy expenditure, energy intake, and adverse events were also investigated. Results: The AVG group lost more weight than the control group (-2.2 ± 0.9 vs. -0.5 ± 0.7 kg, P &lt
0.001). They also exhibited more important reductions of BMI, waist and hip circumferences, and body fat (P &lt
0.05). During the 40-d period, subjects expended an estimated 4682 ± 2874 kcal just by playing AVG. Daily energy intake was reduced by 206 ± 559 kcal. There were significant positive correlations between playing frequency, total playing time, total energy expenditure during the 40-d period, and decrease in daily energy intake respectively, and weight loss (P &lt
0.05). Playing time data suggested no conflict with baby care activities. Conclusions: AVGs could represent an interesting spare physical activity for postpartum women. In the present study, these games promoted physical activity, induced a reduction of energy intake, and subsequently minimized weight retention. © 2014 by the American College of Sports Medicine.

本研究は、仮設住宅に居住している東日本大震災被災者の食物摂取状況を把握することを目的とした。対象者は、18歳以上の岩手県釜石市H地区の仮設住宅居住者72名(男性22名、女性50名)であった。調査は2011年10月に実施した。1日の食物摂取状況は24時間思い出し法(24HR)を用いて評価した。また、対象者には、東日本大震災被災者健康調査の食事に関する9項目の質問票(FFQ-H)への回答を依頼した。FFQ-Hの質問項目は、数日間を振り返った1日あたりの食事回数と、8つの食品群(主食、肉、魚介類、卵、豆類、野菜、果物、乳製品)の1日あたりの摂取回数(0、1、2、3、4回以上)とした。24HRによって評価した1日あたり栄養素および食物摂取状況の中央値[25-75パーセンタイル]は、エネルギー量1903kcal[1493-2238]、総たんぱく質70.7g[47.4-84.7]、ビタミンB1 0.8mg[0.6-1.4]、ビタミンB21.3mg[0.9-1.9]、ビタミンC 86mg[50-144]、食塩相当量12.1g[8.2-14.3]、野菜類220g[158-329]、果物122g[0-161]であった。エネルギー、栄養素、群別食品の摂取状況を2009年国民健康・栄養調査の性・年齢階級別摂取量の結果と比較すると、72名中、ビタミンC48名、野菜53名、果物42名で低値であった。24HRとFFQ-Hによる食物摂取回数間の相関係数は0.03〜0.43の範囲であった。本研究の対象者である岩手県釜石市H地区の仮設住宅居住者は、2009年国民健康・栄養調査の結果と比較して、ビタミンC、野菜、果物の摂取量が少ないことが示唆された。(著者抄録)

Objective: To evaluate the association between adiponectin complexes (high-molecular-weight [HMW], middle-molecular-weight [MMW], and low-molecular-weight [LMW] adiponectin) and diabetes.
Design and Methods: We conducted a case-control study, based on a cohort in Saku, Japan. Among 2565 participants, 300 participants with diabetes and 300 matched controls (430 men and 170 women) were analyzed.
Results: After adjusting for age, physical activity, hypertension, family history, alcohol use, smoking, and menopausal status, total, HMW, and LMW, but not MMW adiponectin levels were inversely associated with diabetes: total adiponectin, odds ratio comparing the highest with the lowest quartiles, 0.46 (95% confidence interval, 0.25-0.82; P for trend = 0.046); HMW, 0.40 (95%CI, 0.22-0.72; P = 0.046); MMW, 1.04 (95%CI, 0.60-1.77; P = 0.81); and LMW, 0.51 (95%CI, 0.29-0.89; P = 0.01). The associations between total and HMW adiponectin and diabetes attenuated after adjustment for BMI (P = 0.15 and 0.13, respectively), but LMW remained (P = 0.04). When stratified by sex, LMW adiponectin levels were associated with diabetes in men only. None of the associations were significant after adjustment for HOMA-IR.
Conclusions: Decreased LMW, total, and HMW adiponectin levels are associated with diabetes. These associations may be secondary to adiposity or insulin resistance.

The ACTN3 R577X genotype has been found to associate with sprint/power phenotypes in all elite athlete cohorts investigated. This association has not been extensively studied in elite Asian athletes. The present study was undertaken to investigate the association between the ACTN3 R577X genotype and elite Japanese track and field athlete status. 299 elite Japanese track and field athletes (134 sprint/power athletes; 165 endurance/middle-power athletes) and 649 Japanese controls were genotyped for the ACTN3 R577X polymorphism. All athletes were of national or international level. Sprint/power athletes showed a higher frequency of RR+RX genotype than controls (111/134 [82.8%] vs. 478/649 [73.7%], P=0.025 under the R-dominant model), while there was no significant difference between endurance/middle-power athletes and controls (126/165 [76.4%] vs. 478/649 [73.7%], P=0.48 under the R-dominant model). Sprinters with the RR+RX genotype had significantly faster personal best times for the 100m than those with XX genotype (10.42 +/- 0.05s vs. 10.64 +/- 0.09s, P=0.042); no such association was found in the 400m sprinters (47.02 +/- 0.36s vs. 47.56 +/- 0.99s, P=0.62). ACTN3 R577X genotype is associated with sprint/power performance in elite Japanese track and field athletes, especially short sprint performance.

OBJECTIVES: This study aimed to examine the association between meeting the reference value for physical activity (PA) defined in the &quot;Physical activity reference for health promotion 2013&quot; recommendations or incremental increases in PA (add 10-minute per day) and the prevalence of metabolic syndrome (MS).METHODS: A total of 906 adults aged 23-64 years participated in this cross-sectional study. The amount of moderate to vigorous PA was measured with a tri-axial accelerometer. The participants were classified into 2 groups-those with a PA level greater than or equal to the reference value of 23 metabolic equivalents (METs)-hours/week versus those with a PA level less than the reference value. Pre-MS and MS were determined based on the diagnostic criteria used in Japan. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for the prevalence of pre-MS and MS by adherence with the PA reference value were analyzed using a multivariable logistic regression model. Furthermore, adjusted ORs were calculated for each 3.5 METs-hours/week increase in PA, which is comparable to 10-minute increments of PA such as walking.RESULTS: The prevalence rates of pre-MS and MS were 10.3% (n=93) and 4.4% (n=40), respectively. The adjusted OR (95% CI) for the prevalence of pre-MS/MS among the participants meeting the PA reference compared with those not meeting the reference was 0.49 (0.33-0.74). Each 3.5 METs-hours/week increase in PA was associated with a lower adjusted OR for the prevalence of pre-MS/MS (OR 0.92, 95% CI 0.87-0.98).CONCLUSION: Our results suggest that meeting the reference value for PA (as defined in the &quot;Physical activity reference for health promotion 2013&quot; recommendations) and an increase in PA (add 10-minute) are both associated with a lower prevalence of pre-MS/MS.

OBJECTIVES: The mean number of steps measured in the National Health and Nutrition Survey is employed for the assessment of physical activity/exercise in &quot;Health Japan 21,&quot; and is used to represent the amount of physical activity/exercise that citizens engage in. In this study, we clarified the characteristics of the data on the number of steps, drawn from the National Health and Nutrition Survey.METHODS: Among the data from the National Health and Nutrition Surveys conducted from 2008 to 2010, data from 21,914 participants on daily number of steps and pedometer attachment were analyzed. On a nutritional intake questionnaire, subjects who responded on the physical status item that they had attached the pedometer all day long were assigned to the &quot;Whole-day-attached&quot; group. Their means, medians, outliers, and frequency distribution were then compared with those in a &quot;Non- whole-day-attached&quot; group.RESULTS: Subjects assigned to the &quot;Non- whole-day-attached&quot; group accounted for about 8% of cases in 2008, 2009, and 2010. In all three years, the mean number of steps in the &quot;Whole-day-attached&quot; group was 1,076 to 1,472 higher than that in the &quot;Non-whole-day-attached&quot; group. In both groups, outliers were present, and the frequency distribution showed a broad range on the side indicating a higher number of steps. Accordingly, the mean value was higher than the median value by approximately 600 steps.CONCLUSION: As data on the number of steps measured in the National Health and Nutrition Survey includes individuals not attaching the pedometer all day (approximately 8% of cases), the data are not normally distributed. Therefore, when utilizing these data as representative of citizens&#039; physical activity/exercise, their characteristics should be taken into consideration.

BACKGROUND: Several active video game (AVG) intervention studies failed in showing an increase in physical activity by using accelerometry measurements.
OBJECTIVE: To test the validity of accelerometry for monitoring AVG playing intensity.
METHOD: Twenty-two adults performed 80 activities included in the Wii Sports and Wii Fit Plus series. The energy expenditure (EE) and subsequent MET values were measured by indirect calorimetry using metabolic chambers. Subjects wore an accelerometer-based monitor displaying MET values. For each activity, METs values obtained from indirect calorimetry and accelerometry were compared. Each activity was classified as light or moderate to vigorous physical activity (LPA: &lt; 3METs or MVPA: &gt;= 3METs) for the two methods.
RESULTS: AVG intensities have been slightly but significantly underestimated by the acceleromater-based monitor compared to the indirect calorimetry (2.5 +/- 1.0 instead of 2.7 +/- 0.9 METs). Fourty percent of activities have been significantly misestimated, and 20% have been misclassified.
CONCLUSION: Those results point out the potential bias of accelerometry measurements for evaluating AVG intensities. Because average AVG intensity lays at the boundary between LPA and MVPA classes, misclassifications can frequently occur. Accelerometry data should be interpreted with caution in intervention studies using AVG.

This study investigated the longitudinal changes in the physical activity of the Great East Japan Earthquake victims living in temporary housing. Thirty-nine residents (10 men and 29 women) living in temporary housing in Kamaishi City, Iwate Prefecture, participated in a health survey in 2012. Among these residents, 31 who also participated in a health survey in 2011 were included in a longitudinal study of physical activity. The physical activity for two weeks after the health survey was measured using a tri-accelerometer. During the one-year period from 2011 to 2012, the median daily step counts changed from 4,959 (interquartile range: 2,910-6,029) steps/day to 4,618 (interquartile range: 3,007-7,123) steps/day. The step counts increased for 18 people (56%). The amount of moderate to vigorous physical activity changed from 13.3 (interquartile range: 7.7-22.4) METs h/week to 16.1 (interquartile range: 6.3-25.2) METs h/week. An increase in daily step counts occurred for 14 out of 21 subjects who were &lt;65 years old (67%) and only 3 out of 10 subjects who were ≥65 years old (30%). It was suggested that physical activity levels increased because the interquartile range of step counts moved in the direction of an increase and the median amount of moderate to vigorous physical activity increased. However, increasing support for physical activity in the future is required because the physical activity levels of the Great East Japan Earthquake victims who were living in temporary housing were still low compared to the national and regional averages.

Background: It is unclear whether light physical activity is beneficially associated with insulin resistance, similar to moderate and/or vigorous physical activity. This cross-sectional study was performed to determine the relationship between the amount of light physical activity, as determined with a triaxial accelerometer, and insulin resistance. Methods: A total of 807 healthy men and women participated in this study. Physical activity was measured using a triaxial accelerometer worn for 28 days and summarized as light intensity (1.1-2.9 METs) or moderate to vigorous intensity (≥ 3.0 METs). Insulin resistance was evaluated by HOMA-R (FPG [mg/dL] × IRI [μU/mL]/405). Results: The daily time spent in light physical activity was inversely associated with HOMA-R (r = -0.173, P &lt
0.05). After adjustment for confounders, the association between light physical activity and HOMA-R remained statistically significant (β = -0.119, P &lt
.05). Light physical activity remained significantly associated with HOMA-R following further adjustment for moderate to vigorous intensity activity (β = -0.125, P &lt
.05). Similar results were observed when light physical activity was modeled as quartiles, especially in elderly women. Conclusions: These cross-sectional data suggest that light-intensity physical activity is beneficially associated with insulin resistance in elderly Japanese women. © 2014 Human Kinetics, Inc..

Background: In "Physical Activity Reference for Health Promotion 2013" the Japan Ministry of Health, Labour and Welfare publication gives reference values for cardiorespiratory fitness (CRF) required for good health. We examined the associations between the CRF reference values and incidence of type 2 diabetes.
Methods: This prospective cohort study enrolled 4633 nondiabetic Japanese men aged 20 to 39 years at baseline. CRF was measured using the cycle ergometer test, and maximal oxygen uptake was estimated. On the basis of the CRF reference value, participants were classified into 2 groups: those with values less than the reference value (under-RV) and those with values equal to or greater than reference value (over-RV). Hazard ratios (HRs) and 95% CIs for incident type 2 diabetes were estimated using a Cox proportional hazards model.
Results: A total of 266 participants developed type 2 diabetes during the 14 years of follow-up. As compared with the under-RV group, the over-RV group had a significantly lower multivariable-adjusted HR for type 2 diabetes (HR 0.67; 95% CI, 0.51-0.89). In receiver operating characteristic analysis, the optimal CRF cut-off value for predicting incident type 2 diabetes was 10.8 metabolic equivalents (sensitivity, 0.64; specificity, 0.64), which was close to the CRF reference value of 11.0 metabolic equivalents.
Conclusions: The reference CRF value appears to be reasonably valid for prevention of type 2 diabetes, especially among Japanese men younger than 40 years. Development of type 2 diabetes can be prevented by maintaining a CRF level above the reference value.

The objective of the present study was to investigate whether a previously reported apparent negative relationship between fat mass and daily physical activity in Japanese adult women would also be observed in Japanese adult men. The subjects were grouped into quartiles of BMI and body fat percentage (%BF). The number of steps walked each day and the duration of light- to vigorous-intensity physical activity were assessed by an accelerometer over the same period of time as for the doubly labelled water experiment. The results showed that BMI negatively correlated with the number of steps and time spent in moderate-intensity physical activity, whereas %BF showed a negative relationship with physical activity-related energy expenditure (PAEE)/body weight (BW) and physical activity level. The analysis of data using %BF quartiles revealed that PAEE/BW decreased from the second quartile in which the BMI was &lt;25kg/m(2). These observations are similar to those reported in our previous study in Japanese adult women. These cross-sectional studies cannot prove causality, and that obesity causes physical inactivity may be the case. However, the results of the present study provide information regarding which physical activity variables should be used in longitudinal studies.

BACKGROUND:It is unclear whether light physical activity is beneficially associated with insulin resistance, similar to moderate and/or vigorous physical activity. This cross-sectional study was performed to determine the relationship between the amount of light physical activity, as determined with a triaxial accelerometer, and insulin resistance.;METHODS:A total of 807 healthy men and women participated in this study. Physical activity was measured using a triaxial accelerometer worn for 28 days and summarized as light intensity (1.1-2.9 METs) or moderate to vigorous intensity (≥ 3.0 METs). Insulin resistance was evaluated by HOMA_R (FPG [mg/dL] × IRI [μU/mL]/405).;RESULTS:The daily time spent in light physical activity was inversely associated with HOMA_R (r = -0.173, P &lt; 0.05). After adjustment for confounders, the association between light physical activity and HOMA_R remained statistically significant (β = -0.119, P &lt; .05). Light physical activity remained significantly associated with HOMA_R following further adjustment for moderate to vigorous intensity activity (β = -0.125, P &lt; .05). Similar results were observed when light physical activity was modeled as quartiles,

BACKGROUND:In &quot;Physical Activity Reference for Health Promotion 2013&quot; the Japan Ministry of Health, Labour and Welfare publication gives reference values for cardiorespiratory fitness (CRF) required for good health. We examined the associations between the CRF reference values and incidence of type 2 diabetes.;METHODS:This prospective cohort study enrolled 4633 nondiabetic Japanese men aged 20 to 39 years at baseline. CRF was measured using the cycle ergometer test, and maximal oxygen uptake was estimated. On the basis of the CRF reference value, participants were classified into 2 groups: those with values less than the reference value (under-RV) and those with values equal to or greater than reference value (over-RV). Hazard ratios (HRs) and 95% CIs for incident type 2 diabetes were estimated using a Cox proportional hazards model.;RESULTS:A total of 266 participants developed type 2 diabetes during the 14 years of follow-up. As compared with the under-RV group, the over-RV group had a significantly lower multivariable-adjusted HR for type 2 diabetes (HR 0.67; 95% CI, 0.51-0.89). In receiver operating characteristic analysis, the optimal CRF cut-off value for predicting incident

The purpose of the present study was to identify mitochondrial DNA (mtDNA) polymorphisms and rare variants that associate with elite Japanese athletic status. Subjects comprised 185 elite Japanese athletes who had represented Japan at international competitions (that is, 100 endurance/middle-power athletes: EMA; 85 sprint/power athletes: SPA) and 672 Japanese controls (CON). The entire mtDNA sequences (16 569 bp) were analyzed by direct sequencing. Nucleotide variants were detected at 1488 sites in the 857 entire mtDNA sequences. A total of 311 variants were polymorphisms (minor allele frequency &gt;= 1% in CON), and the frequencies of these polymorphisms were compared among the three groups. The EMA displayed excess of seven polymorphisms, including subhaplogroup D4e2- and D4g-specific polymorphisms, compared with CON (P &lt; 0.05), whereas SPA displayed excess of three polymorphisms and dearth of nine polymorphisms, including haplogroup G-and subhaplogroup G2a-specific polymorphisms, compared with CON (P &lt; 0.05). The frequencies of 10 polymorphisms, including haplogroup G-and subhaplogroup G2a-specific polymorphisms, were different between EMA and SPA (P &lt; 0.05): although none of these polymorphisms differed significantly between groups after correcting for multiple comparison (false discovery rate q-value &gt;= 0.05). The number of rare variants in the 12S ribosomal RNA and NADH dehydrogenase subunit I genes were also higher in SPA than in CON (P &lt; 0.05). Analysis of the entire mtDNA of elite Japanese athletes revealed several haplogroupand subhaplogroup-specific polymorphisms to be potentially associated with elite Japanese athletic status.

Objectives: Age-related arterial stiffening and reduction of arterial elasticity are attenuated in individuals with high levels of cardiorespiratory fitness. Viscosity is another mechanical characteristic of the arterial wall; however, the effects of age and cardiorespiratory fitness have not been determined. We examined the associations among age, cardiorespiratory fitness and carotid arterial wall viscosity.
Methods: A total of 111 healthy men, aged 25-39 years (young) and 40-64 years (middle-aged), were divided into either cardiorespiratory fit or unfit groups on the basis of peak oxygen uptake. The common carotid artery was measured noninvasively by tonometry and automatic tracking of B-mode images to obtain instantaneous pressure and diameter hysteresis loops, and we calculated the effective compliance, isobaric compliance and viscosity index.
Results: In the middle-aged men, the viscosity index was larger in the unfit group than in the fit group (2533 vs. 2018 mmHg.s/mm, respectively: P&lt;0.05), but this was not the case in the young men. In addition, effective and isobaric compliance were increased, and viscosity index was increased with advancing age, but these parameters were unaffected by cardiorespiratory fitness level.
Conclusion: These results suggest that the wall viscosity in the central artery is increased with advancing age and that the age-associated increase in wall viscosity may be attenuated in cardiorespiratory fit men.

Objective: To investigate the link between serum interleukin-18 (IL-18) levels and physical activity in Japanese men.
Methods: A total of 81 men (45.7617.6 years old) was enrolled in this cross-sectional investigation study. We assessed anthropometric and body composition parameters. Serum IL-18 levels, physical activity by uniaxial accelerometers, peak oxygen uptake and metabolic risk parameters were also evaluated.
Results: Serum IL-18 levels were 179.4 +/- 84.7 pg/mL. Physical activity evaluated by Sigma[metabolic equivalents x h per week (METs.h/w)] was significantly and negatively correlated with serum IL-18 levels (r = -0.252, p = 0.0235). These associations remained even after adjusting for age, peak oxygen uptake and other confounding factors.
Conclusion: Serum IL-18 levels were closely associated with physical activity independent of peak oxygen uptake in Japanese men.

Objective: Lower birth weight is associated with higher insulin resistance in later life. The aim of this study was to determine whether cardiorespiratory fitness modifies the association of birth weight with insulin resistance in adults.
Methods: The subjects were 379 Japanese individuals (137 males, 242 females) aged 20-64 years born after 1943. Insulin resistance was assessed using a homeostasis model assessment of insulin resistance (HOMA-IR), which is calculated from fasting blood glucose and insulin levels. Cardiorespiratory fitness (maximal oxygen uptake, VO(2)max) was assessed by a maximal graded exercise test on a cycle ergometer. Birth weight was reported according to the Maternal and Child Health Handbook records or the subject's or his/her mother's memory.
Results: The multiple linear regression analysis revealed that birth weight was inversely associated with HOMA-IR (beta = -0.141, p = 0.003), even after adjustment for gender, age, current body mass index, mean blood pressure, triglycerides, HDL cholesterol, and smoking status. Further adjustments for VO(2)max made little difference in the relationship between birth weight and HOMA-IR (beta = -0.148, p = 0.001), although VO(2)max (beta = -0.376, p&lt;0.001) was a stronger predictor of HOMA-IR than birth weight.
Conclusions: The results showed that the association of lower birth weight with higher insulin resistance was little modified by cardiorespiratory fitness in adult life. However, cardiorespiratory fitness was found to be a stronger predictor of insulin resistance than was birth weight, suggesting that increasing cardiorespiratory fitness may have a much more important role in preventing insulin resistance than an individual's low birth weight.

Background: During the year after the Great East Japan Earthquake on March 11, 2011, the health conditions and lifestyles of survivors were extensively surveyed. We examined the relationship between living conditions and dietary pattern among survivors.
Methods: A total of 10 466 survivors aged 18 years or older (25% of the population of that age in the area) participated in a survey of Iwate Prefecture. The average frequency of daily consumption of 8 food groups was determined by questionnaire. After excluding staple foods, which were consumed 3 times a day by 5% of participants, factor analysis was performed on 7 food groups among 9789 people (3795 men, 5994 women).
Results: Factor analysis identified 2 dietary patterns-prudent and meat. The prudent dietary pattern is characterized by high intakes of fish and shellfish, soybean products, vegetables, fruit, and dairy products and was more evident among older participants and women. The meat dietary pattern is characterized by high intakes of meat and eggs and was more evident among younger participants and men. Age-adjusted multiple logistic regression analyses showed that male and female current smokers and men and women living in difficult conditions were likely to have a lower prudent dietary pattern score; male current smokers and male daily alcohol drinkers were likely to have a higher meat dietary pattern score.
Conclusions: During the year after the earthquake, the prudent dietary pattern was associated with better living conditions among survivors, whereas the meat dietary pattern was not.

Background: Diabetes is an important risk factor for cardiovascular disease, certain types of cancer, and death, and self-reports are one of the most convenient methods for ascertaining diabetes status. We evaluated the validity of diabetes self-reports among Japanese who participated in a health checkup.
Methods: Self-reported diabetes was cross-sectionally compared with confirmed diabetes among 2535 participants aged 28 to 85 years in the Saku cohort study. Confirmed diabetes was defined as the presence of at least 1 of the following: fasting plasma glucose (FPG) level of 126 mg/dL or higher, 2-hour post-load glucose (2-hPG) level of 200 mg/dL or higher after a 75-gram oral glucose tolerance test, glycated hemoglobin (HbA1c) level of 6.5% or higher, or treatment with hypoglycemic medication(s).
Results: Of the 251 participants with self-reported diabetes, 121 were taking hypoglycemic medication(s) and an additional 69 were classified as having diabetes. Of the 2284 participants who did not self-report diabetes, 80 were classified as having diabetes. These data yielded a sensitivity of 70.4%, a specificity of 97.3%, a positive predictive value of 75.7%, and a negative predictive value of 96.5%. The frequency of participants with undiagnosed diabetes was 3.0%. Of these, 64.2% had FPG within the normal range and were diagnosed by 2-hPG and/or HbA1c.
Conclusions: Our findings provide additional support for the use of self-reported diabetes as a measure of diabetes in epidemiologic studies performed in similar settings in Japan if biomarker-based diagnosis is difficult.

We investigated the effect of macrophage differentiation on the chemotactic activity to invade local damaged myoblasts using in vitro models of muscle injury. We found that: 1) the chemotactic activity of macrophages toward areas of damaged myoblasts might be induced more by live myoblasts than dead ones, 2) the chemotactic activity of macrophages is not due to velocity, but depends on the directionality toward damaged myoblast cells, and 3) macrophage differentiation strongly influence the chemotactic activity toward damaged myoblast cells through the expression of CCR2 and/or F-actin. (c) 2013 Elsevier B.V. All rights reserved.

PURPOSE: Polymorphic variation in the angiotensin-converting enzyme (ACE) and α-actinin-3 (ACTN3) genes has been reported to be associated with endurance and/or power-related human performance. Our aim was to investigate whether polymorphisms in ACE and ACTN3 are associated with elite swimmer status in Caucasian and East Asian populations. METHODS: ACE I/D and ACTN3 R577X genotyping was carried out for 200 elite Caucasian swimmers from European, Commonwealth, Russian, and American cohorts (short and middle distance, ≤400 m, n = 130; long distance, >400 m, n = 70) and 326 elite Japanese and Taiwanese swimmers (short distance, ≤100 m, n = 166; middle distance, 200-400 m, n = 160). Genetic associations were evaluated by logistic regression and other tests accommodating multiple testing adjustment. RESULTS: ACE I/D was associated with swimmer status in Caucasians, with the D allele being overrepresented in short-and-middle-distance swimmers under both additive and I-allele-dominant models (permutation test P = 0.003 and P = 0.0005, respectively). ACE I/D was also associated with swimmer status in East Asians. In this group, however, the I allele was overrepresented in the short-distance swimmer group (permutation test P = 0.041 and P = 0.0098 under the additive and the D-allele-dominant models, respectively). ACTN3 R577X was not significantly associated with swimmer status in either Caucasians or East Asians. CONCLUSIONS: ACE I/D associations were observed in these elite swimmer cohorts, with different risk alleles responsible for the associations in swimmers of different ethnicities. The functional ACTN3 R577X polymorphism did not show any significant association with elite swimmer status, despite numerous previous reports of associations with "power/sprint" performance in other sports.

Background Regular aerobic exercise prevents and reverses arterial stiffening, but the association between resistance training and arterial stiffness is unclear.
Aim This study was performed to conduct a systematic review and meta-analysis of randomised controlled clinical trials (RCTs) assessing the associations between resistance training and changes in arterial stiffness.
Methods MEDLINE and SPORTDiscus databases were searched from January 1980 through to April 2011. RCTs evaluating the ability of resistance training to increase arterial stiffness in comparison with a control group were included in the meta-analysis. Two independent reviewers extracted data and assessed the quality of the included studies. Data from 185 reports of eight RCTs (193 participants) were included. Pooled mean differences in arterial stiffness indices (carotid arterial beta stiffness and pulse wave velocity (PWV)) between intervention and control groups were calculated using a random-effects model.
Results The overall association of resistance training versus control with relative changes in carotid beta index or PWV (eight studies; 193 participants) was 10.7% (95% CI 3.4% to 18.0%; I-2, 89%; heterogeneity, p&lt;0.001). Five studies indicated that resistance training in young subjects (n=115) was significantly associated with an increase in stiffness index of 14.3% (95% CI 8.5% to 20.1%; I-2, 71%; heterogeneity, p&lt;0.001) compared with controls. However, three studies showed that resistance training in middle-aged subjects (n=78) was not associated with changes in arterial stiffness. In addition, although high-intensity resistance training (n=87) was significantly associated with an increase in stiffness of 11.6%, moderate-intensity resistance training (n=106) showed no such association.
Conclusion High-intensity resistance training is associated with increased arterial stiffness in young subjects with low baseline levels of arterial stiffness.

Preproghrelin gene single-nucleotide polymorphisms are possible predisposing factors to obesity and other metabolic syndromes. To study the correlation between genotypes and obesity, we recruited 117 obese Japanese women (BMI, 25.0-41.1; average, 31.1). Minor homozygotes for five preproghrelin gene polymorphisms, namely, -1500C &gt; G (rs3755777), -1062G &gt; C (rs26311), -994C &gt; T (rs26312) (promoter region), Leu72Met (rs696217) (exon 2), and +3056T &gt; C (rs2075356) (intron 2), had high values of total and visceral fat areas, waist circumference, and BMI, indicating significant correlation of the polymorphisms with obesity and fat metabolism. Here, we studied the relationship between the genotypes and dietary tendency. Self-administered Diet History Questionnaire showed that total food intake, sugar, and dairy product intake were low in +3056C/C women. Their energy, protein, fat, and meat intake was also low. Energy balance calculation showed considerably reduced fat and protein consumption. Dietary habits were surveyed using Sakata's Questionnaire on Eating Behavior. Of the genotypes, -1062C/C women showed low scores for "motivation for eating" and "eating because of stress or something else." Thus, surprisingly, it was revealed that minor homozygotes for preproghrelin gene polymorphisms were light eaters, did not prefer fat or protein, and apparently had a poor appetite, although they were predisposed to obesity. (C) 2012 Elsevier Ltd. All rights reserved.

Background: A reduction in adiposity may be associated with an improvement in insulin sensitivity and β-cell function as well as cardiovascular disease (CVD) risk factors; however, few studies have investigated these associations in a longitudinal setting. Methods: To investigate these associations over a 1-year period, we conducted an observational analysis of 196 Japanese subjects with obesity in the Saku Control Obesity Program. We investigated the relations between changes in adiposity (body mass index [BMI], waist circumference, subcutaneous fat area [SFAT], and visceral fat area [VFAT]) and changes in HbA1c, fasting plasma glucose (FPG), insulin sensitivity index (ISI), the homeostasis model assessment β cell function (HOMA-β), lipids, and blood pressure. Results: All adiposity changes were positively associated with HbA1c and FPG changes. Reductions in BMI and VFAT were associated with HOMA-β reduction. Reductions in all adiposity measures were associated with an improvement in the ISI. Changes in most adiposity measures were positively associated with changes in blood pressure and lipid levels, except for LDL. Conclusion: The present findings provide additional supportive evidence indicating that a reduction in adiposity may lead to an improvement in insulin sensitivity and the reduction of CVD risk factors in obese individuals. © 2013 Goto et al.

Fujie S, Iemitsu M, Murakami H, Sanada K, Kawano H, Gando Y, Kawakami R, Miyachi M. Higher cardiorespiratory fitness attenuates arterial stiffening associated with the Ala54Thr polymorphism in FABP2. Physiol Genomics 45: 237-242, 2013. First published January 29, 2013; doi:10.1152/physiolgenomics.00089.2012.-Fatty acid binding protein 2 (FABP2) Ala54Thr polymorphism is a candidate gene associated with the risk of cardiovascular disease. Habitual exercise brings higher cardiorespiratory fitness and results in the improvement of cardiovascular disease risk. However, the effect of cardiorespiratory fitness level and FABP2 Ala54Thr polymorphism on the risk of cardiovascular diseases remains unclear. In the present study, a cross-sectional investigation of 837 Japanese men and women was performed to clarify the effects of cardiorespiratory fitness on the relationship between risk of cardiovascular disease and FABP2 Ala54Thr gene polymorphism. The study subjects were divided into high-cardiorespiratory fitness (High-Fit) and low-cardiorespiratory fitness (Low-Fit) groups based on the median value of peak oxygen uptake in each sex and decade. The FABP2 Ala54Thr polymorphism did not significantly affect carotid beta-stiffness or blood pressure. In the Low-Fit group, carotid beta-stiffness, systolic blood pressure, and diastolic blood pressure were higher for individuals with the Ala/Ala genotype compared with those with the Ala/Thr or Thr/Thr genotype, whereas no differences were observed in the High-Fit group. Additionally, serum triglyceride and plasma glucose levels were lower and serum high-density lipoprotein cholesterol levels were higher in the High-Fit group compared with the Low-Fit group; the FABP2 Ala54Thr polymorphism did not significantly affect these parameters. These results suggest that the higher cardiorespiratory fitness may attenuate the changes in central arterial stiffness and blood pressure that are associated with the FABP2 genotype.

This study was performed to assess the validity and reproducibility of a questionnaire on physical activity status used for health surveying among victims of the Great East Japan Earthquake. Seventy-four residents (21 men and 53 women) living in temporary housing in Kamaishi City, Iwate Prefecture, participated in this study. The physical activity status questionnaire was composed of 4 questions regarding the frequency of performing domestic and occupational physical activities, the frequency of leaving their residence, walking duration per day, and sedentary time. The physical activity level for 2 weeks was measured using a tri-accelerometer to validate the responses to the questionnaire. Test-retest reproducibility was examined at 2-week intervals. The physical activity levels were 4,521 +/- 2,266 steps/day for men and 4,533 +/- 2,070 steps/day for women. There was a significant difference in step count between those responding differently to the 3 options in the questionnaire regarding average walking duration per day: those who reported walking for &gt; or = 60 min, 30-60 min, or &lt; or = 30 min had step counts of 5,343 +/- 1,757, 4,760 +/- 1,752, and 3,063 +/- 1,772 steps/day, respectively (P &lt; 0.05). When the response options for 3 questions (excluding those for sedentary time) were given scores (a higher score for a higher physical activity level), there were significant correlations between question score and step count (r = 0.486, P &lt; 0.05) and the amount of moderate to vigorous physical activity (r = 0.342, P &lt; 0.05). The test-retest trial showed a moderate degree of reproducibility, with weighted K coefficients of 0.41-0.65. Three questions on physical activity levels may allow assessment of an individual&#039;s physical activity level, with a moderate degree of reproducibility.

The authors investigated the effects of low-intensity resistance training on muscle size and strength in older men and women. Thirty-five participants (age 59-76 yr) were randomly assigned to 2 groups and performed low-intensity (50% of 1-repetition maximum) knee-extension and -flexion exercises with either slow movement and tonic force generation (LST; 3-s eccentric, 3-s concentric, and 1-s isometric actions with no rest between repetitions) or normal speed (LN; 1-s concentric and 1-s eccentric actions with 1-s rests between repetitions) twice a week for 12 wk (2-wk preparation and 10-wk intervention). The LST significantly increased thigh-muscle thickness, as well as isometric knee-extension and -flexion strength. The LN significantly improved strength, but its hypertrophic effect was limited. These results indicate that even for older individuals, the LST can be an effective method for gaining muscle mass and strength.

Several studies have shown that low cardiorespiratory fitness (CRF) or heavy alcohol consumption is risks of total or certain types of cancer death. However, the combined influence of CRF and drinking habits on total cancer mortality is not clear. The purpose of this study was to investigate the joint effect of CRF and drinking habits on total cancer mortality among Japanese men. We evaluated the CRF and drinking habits on risk of total cancer mortality in 8,760 Japanese men (age: 19-59 yr) who were given a submaximal exercise test, a medical examination test, and questionnaires on their health habits. CRF was measured using a cycle ergometer test, and the men were classified into two categories by CRF levels based on the reference value of CRF (R-CRF) in "Physical Activity Reference for Health Promotion 2013" (Under R-CRF and Over R-CRF). Also, the men were assigned to Non Drinking, Moderate Drinking, and Heavy Drinking categories. There were 178 cancer deaths during the 20-yr follow-up period. Relative risk and 95% confidence intervals for total cancer mortality were obtained using the Cox proportional hazards model while adjusting for age, body mass index, systolic blood pressure, and smoking habits. Using the Under R-CRF &amp
Heavy Drinking group as reference, the relative risk and 95% confidence intervals were 0.37 (0.16-0.85) for the Over R-CRF &amp
Non Drinking group. This result suggests that Japanese male with a high CRF and a low drinking habit have a lower risk of total cancer mortality.

Conclusion: Haplogroup D4b, especially subhaplogroup D4b2, may be one of the modifiers associated with the phenotypic expression of hereditary hearing loss (HL). Objectives: The present study investigated the association between suspected hereditary HL and 12 major mtDNA haplogroups in a Japanese population. Besides the mutations of mitochondrial DNA, many modifiers including environmental factors and genetic polymorphisms are involved in HL. Methods: The subjects comprised 373 unrelated Japanese patients with suspected hereditary HL and 480 controls. Twenty of the 373 patients were excluded from the study because the m. 1555A&gt;G or the m. 3243A&gt;G mutation had been detected in them. The mitochondrial haplotypes were classified into 12 major Japanese haplogroups (i.e. F, B, A, N9a, N9b, M7a, M7b, G1, G2, D4a, D4b, and D5). The frequency of each haplogroup in patients with HL was compared with that of the controls using the chi-squared test. Results: The frequency of the HL patients carrying the mitochondrial haplogroup D4b was significantly higher than that of the controls (37/353 [10.5%] vs 31/480 [6.5%]; OR 1.70 [95% CI 1.03-2.79, p = 0.036]) and evidence for enhancement was found in subhaplogroup D4b2 (32/353 [9.1%] vs 24/480 [5%], OR 1.89 [95% CI 1.09-3.28, p = 0.021]).

BACKGROUND/OBJECTIVES: Little information is available regarding the interactions of sarcopenia and metabolic syndrome (MetS) in the risks of these age-associated diseases in women. The present cross-sectional study was performed to investigate whether the coexistence of sarcopenia and MetS further increases the risks of lifestyle-related diseases in Japanese women.
SUBJECTS/METHODS: Healthy Japanese women (n = 533) aged 30-84 participated in this study. MetS was defined as higher body mass index, fasting plasma glucose, systolic or diastolic blood pressure and blood lipid abnormalities. Appendicular muscle mass and bone mineral density (BMD) were measured using dual-energy X-ray absorptiometry. The criterion of low muscle mass and strength defined median skeletal muscle index (appendicular muscle mass/height(2), kg/m(2)) and handgrip strength.
RESULTS: Two-way ANCOVA with adjustment for age, body fat percentage and whole-body lean tissue mass indicated that sarcopenia and MetS interacted to produce a significant effect on HbA1c, systolic blood pressure, triglycerides and brachial-ankle pulse wave velocity in Japanese women. The systolic blood pressure, triglycerides and brachial-ankle pulse wave velocity were significantly higher in women with coexisting sarcopenia and MetS than in healthy controls or in those with sarcopenia or MetS alone. The HbA1c in the coexisting sarcopenia and MetS group was higher than in healthy controls and sarcopenia subjects.
CONCLUSIONS: The coexistence of sarcopenia and MetS further increases the risks of cardiovascular diseases, such as type 2 diabetes mellitus, hypertension, arterial stiffness and hyperlipidemia even adjustment of age and body composition in adult Japanese women.

Background: Sex hormone-binding globulin (SHBG) levels and sex hormones have been implicated in the pathogenesis of type 2 diabetes and cardiovascular diseases. As fatty liver has been suggested to be a major determinant of SHBG levels, we examined whether the associations of SHBG and testosterone with diabetes were independent of fatty liver.
Methods: We conducted a case-control study that included 300 diabetes cases (215 men and 85 women) and 300 matched controls from the Saku cohort study. Diabetes was defined by either fasting plasma glucose levels &gt;= 126 mg/dL, 2-h post-load glucose levels &gt;= 200 mg/dL after a 75 g oral glucose tolerance test, or diabetes diagnosed by physicians. We fitted conditional logistic regression models to examine the associations between SHBG and total testosterone levels with diabetes by sex. To evaluate the impact of fatty liver, we used the fatty liver index (FLI), a validated measure derived from serum triglyceride levels, body mass index (BMI), waist circumference, and gamma-glutamyltransferase levels.
Results: After adjusting for age, family history of diabetes, smoking, physical activity, BMI, and FLI, SHBG levels were inversely associated with diabetes among women (odds ratio [OR] comparing the highest with the lowest quartiles, 0.13 [95% confidence interval {CI}, 0.02-0.96]), but not among men. Similar patterns were observed in a subgroup analysis restricted to postmenopausal women"(OR, 0.12 [95% CI, 0.01-1.17]). In contrast, testosterone levels were inversely associated with diabetes among men (OR, 0.45 [95% CI, 0.23-0.89]), but not among women.
Conclusions: Our findings suggest that SHBG in women and testosterone in men may be inversely associated with diabetes.

Background: Dietary glycemic index or load is thought to play an important role in glucose metabolism. However, few studies have investigated the relation between glycemic index (GI) or load (GL) and glycemia in Asian populations. In this cross-sectional analysis of a randomized controlled trial, the Saku Control Obesity Program, we examined the relation between the baseline GI or GL and glycemia (HbA1c and fasting plasma glucose [FPG] levels), insulin resistance (HOMA-IR), beta-cell function (HOMA-beta), and other metabolic risk factors (lipid levels, diastolic and systolic blood pressure, and adiposity measures).
Methods: The participants were 227 obese Japanese women and men. We used multiple linear regression models and logistic regression models to adjust for potential confounding factors such as age, sex, visceral fat area, total energy intake, and physical activity levels.
Results: After adjustments for potential confounding factors, GI was not associated with HbA1c, but GL was positively associated with HbA1c. For increasing quartiles of GI, the adjusted mean HbA1c were 6.3%, 6.7%, 6.4%, and 6.4% (P for trend = 0.991). For increasing quartiles of GL, the adjusted mean HbA1c were 6.2%, 6.2%, 6.6%, and 6.5% (P for trend = 0.044). In addition, among participants with HbA1c &gt;= 7.0%, 20 out of 28 (71%) had a high GL (&gt;= median); the adjusted odds ratio for HbA1c &gt;= 7.0% among participants with higher GL was 3.1 (95% confidence interval [CI] = 1.2 to 8.1) compared to the participants with a lower GL (&lt;median). Further, among 16 participants with FPG &gt;= 150 mg/dL, 13 participants (81.3%) had a higher GL; the adjusted odds ratio for FPG &gt;= 150 mg/dL among participants with a higher GL was 8.5 (95% confidence interval = 1.7 to 43.4) compared to those with a lower GL. In contrast, GI and GL were not associated with metabolic risk factors other than glycemia.
Conclusions: Our findings suggest that participants with poor glycemic control tend to have a higher GL in an obese Japanese population.

The present study was undertaken to examine the effect of mitochondrial haplogroups on aerobic and anaerobic performance phenotypes such as maximum oxygen consumption, muscle power, and muscle mass. We recruited 474 healthy Japanese individuals and measured their physical performance phenotypes such as peak oxygen uptake, muscle power, and muscle mass. The genotypes for 186 polymorphisms in the mitochondrial DNA were determined, and the haplotypes were classified into 2 macrohaplogroups (i.e., N and M) and 12 haplogroups (i.e., F, B, A, N9a, N9b, M7a, M7b, G1, G2, D4a, D4b, and D5). When we compared the 2 major Japanese macrohaplogroups, leg extension power (P = 0.0395), leg extension power based on body weight (P = 0.0343), and vertical jump performance (P = 0.0485) were significantly higher in subjects with mitochondrial macrohaplogroup N than in those with macrohaplogroup M. However, peak oxygen uptake was similar between the 2 groups. When we analyzed the 12 haplogroups, all of the measured parameters were similar among them. In conclusion, mitochondrial macrohaplogroup N may be one of the determinant factors of anaerobic physical performance phenotype such as muscle power.

Aim: Sarcopenia is the significant degenerative loss of skeletal muscle mass and strength associated with aging, and it is one of the components of frailty. We previously reported an association between the 29C&gt;T polymorphism in the transforming growth factor-β1 gene (rs1800470) and the prevalence of vertebral fractures in subjects with postmenopausal osteoporosis. The association was not attributable to bone mineral density, which suggests that polymorphism influences some aspects of bone quality that affects strength and/or frailty rather than bone strength itself. Thus, we examined the relationship between genetic polymorphism and lean body mass in a Japanese population. Methods: A total of 479 adults comprising 143 men and 336 women, age 23 to 85years, participated in the present study. Fat-free mass was measured by dual energy X-ray absorptiometry, and the relative skeletal muscle index was calculated as the ratio of appendicular (sum of arms and legs) fat-free mass to the square of height. Results: Total, leg, and appendicular fat-free mass as well as the relative skeletal muscle index were significantly lower in male subjects with CT/TT genotypes compared to those with CC genotype. Female subjects did not show any genotype-dependent differences when analyzed as a group, but when those without menstruation (postmenopausal women) were analyzed, arm fat-free mass was significantly lower in the CT/TT genotypes than in the CC genotype. Conclusions: T allele of the 29C&gt;T polymorphism in the transforming growth factor-β1 gene might be a risk factor of sarcopenia in a Japanese population. © 2011 Japan Geriatrics Society.

Objectives We evaluated anthropometric parameters and physical fitness in elderly Japanese. Methods A total of 2,106 elderly Japanese (749 men and 1,357 women), aged 60-79 years, were enrolled in a crosssectional investigation study. Anthropometric parameters and physical fitness, i.e., muscle strength and flexibility, were measured. Of the 2,106 subjects, 569 subjects (302 men and 267 women) were further evaluated for aerobic exercise level, using the ventilatory threshold (VT). Results Muscle strength in subjects in their 70s was significantly lower than that in subjects in their 60s in both sexes. Two hundred and twenty-nine men (30.6%) and 540 women (39.8%) were taking no medications. In men, anthropometric parameters were significantly lower and muscle strength, flexibility, and work rate at VT were significantly higher in subjects without medications than these values in subjects with medications. In women, body weight, body mass index (BMI), and abdominal circumference were significantly lower, and muscle strength was significantly higher in subjects without medications than these values in subjects with medications. Conclusion This mean value may provide a useful database for evaluating anthropometric parameters and physical fitness in elderly Japanese subjects. © The Japanese Society for Hygiene 2011.

The present study elucidated the effects of habitual rowing exercise on arterial stiffness and plasma levels of the vasoconstrictor endothelin-1 and the vasodilator nitric oxide (NO) in older men. Eleven rowers (68.0 +/- 1.6 years) and 11 sedentary control older men (64.9 +/- 1.1 years) were studied. Peak oxygen uptake (36.0 +/- 1.7 vs. 27.7 +/- 1.9 ml . kg(-1) . min(-1)), leg press power (1346 +/- 99 vs. 1077 +/- 68 W), and HDL-cholesterol (75 +/- 5 vs. 58 +/- 3 mg . ml(-1)) were higher and triglyceride (78 +/- 9 vs. 120 +/- 14 mg . ml(-1)) was lower in rowers than in control participants (all P &lt; 0.05). Arterial stiffness indices (carotid beta-stiffness and cardio-ankle vascular index) and plasma endothelin-1 and NOx (nitrite+nitrate) levels did not differ between the two groups. These results suggest that habitual rowing exercise in older men is associated with high muscle power and aerobic capacity, and favourable blood lipid profile without affecting arterial stiffness or plasma levels of endotheline-1 and NO.

This study evaluated effects of a behavioral approach which placed emphasis on tailored behavior counseling, diet, weight loss and weight maintenance. A one-year randomized controlled trial was conducted among 235 overweight/obese adults in Japan. The intervention group (n=119) received individual-based counseling using a behavioral approach and the changes made in the diet and physical activity were dependent on each participant as much as possible. One year later, the intervention group lost significantly more weight than the control group (-5.0 kg vs. 0.1 kg for men and -3.9 kg vs. -0.2 kg for women). Compared to the control group, the male intervention group reduced overall energy, cereals and dairy products consumption significantly, while increasing green and yellow vegetable intake, and the female intervention group significantly reduced intake of dairy products. Regarding behaviors, both male and female intervention groups increased the number of walking steps and women improved their irregular eating habits compared to those in the control groups. Behavior changes were related to weight loss; participants who maintained the action/maintenance stage or moved to later stages lost significantly more weight than participants who remained in the pre-contemplation/contemplation/preparation stages or regressed to earlier stages. After one-year follow-up, the intervention group maintained significantly lower weights, lower energy intakes and improvements in irregular eating habits. Our behavioral approach led to diet and behavior modification, weight loss and maintenance. Because modified variables differed between men and women, gender-specific approaches may be necessary.

Purpose. To examine behavioral factors related to successful weight maintenance. Methods. Subjects were 90 middle-aged participants who attended a weight loss program and were followed for one year. The subjects were classified into either successful weight maintainers (maintained a weight loss of 5 or more from their initial weight for one year) (SWM) or unsuccessful weight maintainers (USWM), and weight control practice, stress, obstacles, support, and self-efficacy during the program and follow-up period were compared. Results. SWM had mean loss of 12 from their initial weight during the program. They showed a greater improvement in their regularity of eating, walked more, and felt less stress regarding their increased physical activity than the USWM. During the follow-up period, significantly more SWM participants had self-efficacy (for measuring weight, practicing dietary objective, and assessing the practice and keeping records), actually kept records and measured weight more than the USWM participants. In contrast, more USWM participants felt stress about measuring weight. Conclusion. In addition to a substantial initial weight loss due to an increased amount of physical activity, having a higher self-efficacy and consistently keeping records of one's activities, as well as regularly weighing themselves, may be important for successful weight maintenance. © 2012 Makiko Nakade et al.

Elevated fasting plasma homocysteine (Hcy) level is a vascular disease risk factor. Plasma Hcy is affected by 5,10-methylenetetrahydofolate reductase (MTHFR) genotype and dietary folate intake. This cross-sectional study in 434 Japanese adults examined the associations among objectively measured physical activity (PA), plasma Hcy adjusting for dietary folate intake, and MTHFR C677T genotype. Daily PA was measured by triaxial accelerometry and all subjects completed a questionnaire about their dietary habits. Plasma Hcy and MTHFR C677T genotype were determined. Plasma Hcy in subjects with the TT genotype was significantly higher than in those with CC or CT genotype (p &lt; 0.001). Plasma Hcy was significantly different between a parts per thousand yen200 (7.6 +/- A 0.2 nmol/mL) and &lt; 200 A mu g/day (8.3 +/- A 0.3 nmol/mL) folate intake groups (p = 0.003). There were no differences in plasma Hcy adjusting for age, sex, and folate intake between groups according to PA category in all subjects. However, there were significant interactions between time spent in light PA (p = 0.003), vigorous PA (p = 0.001), or inactivity (p = 0.004), and MTHFR genotype. In only the TT genotype, shorter time spent in light PA was associated with higher plasma Hcy than a longer time spent in light PA (11.5 +/- A 3.3 nmol/mL vs. 8.5 +/- A 3.3 nmol/mL, p &lt; 0.001), and longer time spent in vigorous PA and inactivity were associated with higher plasma Hcy (11.8 +/- A 3.3 nmol/mL vs. 8.4 +/- A 3.2 nmol/mL, 11.6 +/- A 3.3 nmol/mL vs. 8.4 +/- A 3.3 nmol/mL, respectively, p &lt; 0.001). In conclusion, light and vigorous PA were associated with plasma Hcy only in the TT genotype, but there were no such associations in all genotypes.

Methods: 1109 Japanese men were categorized by their exercise habits. Clinical data, number of MetS risk factors, and differences in lifestyle-related behaviors of the non-training group (n = 233) and the detraining group (n = 483) were compared with those of the training group (n = 87). Results: Waist circumference and body mass index were significantly higher in the non-training group and the detraining group than in the training group, and also higher in the detraining group than in the non-training group. High-density lipoprotein cholesterol (HDL-C) was lower and low-density lipoprotein cholesterol (LDL-C) was higher in the non-training group and the detraining group than in the training group. Both the non-training group and the detraining group had more MetS risk factors than the training group. The odds ratio for smoking was higher in the detraining group than in the training group. Conclusions: Detraining results in similar degrees of obesity, low HDL-C, high LDL-C, and high MetS risk as non-training. To prevent lifestyle-related diseases, it is particularly important not only to encourage adults to become physically active, but also discourage active young people from discontinuing physical exercise.

The objective of the present study was to investigate the relationship between the indices of body size such as BMI, fat-free mass index (FFMI, FFM/height(2)), fat mass index (FMI, FM/height(2)), and body fat percentage (%BF), and physical activities assessed by the doubly-labelled water (DLW) method and an accelerometer in free-living Japanese adult women. We conducted a cross-sectional study in 100 female subjects ranging in age from 31 to 69 years. Subjects were classified in quartiles of BMI, FFMI, FMI and %BF. Daily walking steps and the duration of light to vigorous physical activity were simultaneously assessed by an accelerometer for the same period as the DLW experiment. Only physical activity-related energy expenditure (PAEE)/FFM and PAEE/body weight (BW) decreased in the highest quartile of BMI. Physical activity level, PAEE/FFM and PAEE/BW decreased in the highest quartile of FMI and %BF, whereas they were not different among quartiles of FFMI. Daily walking steps and the duration of moderate-and vigorous-intensity physical activities decreased or tended to decrease in the highest quartile of FMI and %BF, but did not differ among quartiles of FFMI and BMI. These results clearly showed that Japanese adult women with higher fat deposition obviously had a low level of physical activities assessed by both the DLW method and accelerometry, but those with larger BMI had lower PAEE/FFM and PAEE/BW only. Our data suggest that the relationship between obesity and daily physical activities should be discussed using not only BMI but also FMI or %BF.

The link between cigarette smoking and ventilatory threshold (VT) was investigated. We used data for 407 men and 418 women not taking medication. Habits of cigarette smoking were obtained through interviews by well-trained staff. The influence of cigarette smoking on oxygen uptake, work rate, and heart rate at VT was evaluated. Oxygen uptake at VT in women and work rate at VT in men with cigarette smoking were significantly lower than in subjects without cigarette smoking after adjusting for age. The differences of parameters at VT did not reach significant levels after adjusting for age and exercise habits in both sexes. However, in women without exercise habits, there was significant difference of oxygen uptake at VT between women with and without cigarette smoking after adjusting for age [cigarette smoking (+): 11.5 ± 1.8 ml/ kg/min, cigarette smoking (-): 12.4 ± 2.1 ml/kg/min, p = 0.0006]. The number of cigarettes smoked per day and the Brinkman Index were not clearly correlated with oxygen uptake at VT. A combination of promoting exercise habits and prohibiting cigarette smoking might be recommended for improving the aerobic exercise level, especially in women. © 2010 The Japanese Society for Hygiene.

The peroxisome proliferator-activated receptor gamma 2 (PPARγ2) genotypes are related to obesity and the metabolic syndrome (MetS). A low level of cardiorespiratory fitness is also a strong determining factor in the development of MetS. This cross-sectional study was performed to investigate the influence of the interaction between the PPARγ2 genotype and cardiorespiratory fitness on the risk of MetS. Healthy Japanese men (n = 211) and women (n = 505) participated in this study. All subjects were divided into 8 groups according to sex, fitness level (high and low fitness groups), and age (younger, age &lt; 40 yr; middle-aged/older, age ≥ 40 yr). The PPARγ2 genotypes (Pro12Ala and C1431T) were analyzed by real-time PCR with Taq-Man probes. Two-way ANCOVA with adjustment for age as a covariate indicated that fitness and the CC genotype of C1431T in the PPARγ2 gene interacted to produce a significant effect on MetS risk in younger men and that the risk of MetS in the CC genotype group with low cardiorespiratory fitness was significantly higher than that in the corresponding CT+TT genotypes or in the high fitness groups. There was no significant interaction between fitness and genotype in determining MetS risk in middle-aged/older men or in women in any group. With regard to the Pro12Ala genotype of the PPARγ2 gene, there were no significant differences in fitness or genotype effects nor were there any interactions between measurement variables. We concluded that the CC genotype of C1431T in the PPARγ2 gene together with low cardiorespiratory fitness may increase the risk of MetS in younger men (age &lt; 40 yr), even with adjustment for age. Copyright © 2011 the American Physiological Society.

Aim: Cardiorespiratory fitness (CRF) is independently associated with a reduced risk of cardiovascular disease. Carotid arterial remodeling, which is derived from the interplay between carotid luminal dilation and wall thickening, is also an independent predictor of cardiovascular events. We hypothesized that high CRF may be associated with reduced age-related carotid arterial remodeling. This cross-sectional study was performed to determine the relationships between CRF and age-related luminal dilation and wall thickening.
Methods: A total of 771 adults (180 men and 591 women), under age 40 (young), 40-59 (middle-aged), and over age 60 (older) participated in this study. Subjects in each age category were divided into either high (fit) or low (unfit) CRF groups based on (V) over dotO(2peak). Carotid artery intima-media thickness (IMT) and lumen diameter were measured on ultrasound images. Carotid wall mass was calculated as rho L(pi Re-2-Ri(2)).
Results: Two-way ANOVA indicated a significant interaction (p&lt;0.01) between age and CRF in determining IMT, lumen diameter, and wall mass. In older subjects, IMT, lumen diameter, and wall mass were significantly lower (p&lt;0.05) in the fit than in the unfit group (IMT, 0.69 +/- 0.01 vs. 0.74 +/- 0.01 mm; lumen diameter, 5.99 +/- 0.06 vs. 6.28 +/- 0.06 mm; wall mass, 7.41 +/- 0.25 vs. 8.71 +/- 0.25 mm(3)). Multiple regression analysis indicated that the value of (V) over dotO(2peak) was independently correlated with carotid IMT, lumen diameter and wall mass.
Conclusion: The present study indicated that a high level of CRF is associated with reduced age-related wall thickening and luminal dilation in the carotid artery.

High-intensity resistance training increases muscle size, but reduces arterial compliance. Muscular blood flow reduction (BFR) during low-intensity training has been shown to elicit muscle hypertrophy. However, the effect on arterial compliance is unknown. We examined the effects of walk training with BFR on carotid arterial compliance and muscle size in the elderly adults. Both BFR-walk training (BFR-W, n = 13, 66 +/- 1 year) and control-walk training (CON-W, n = 10, 68 +/- 1 year) groups performed 20 minutes treadmill walking at an exercise intensity of 45% of heart rate reserve, 4 days/week for 10 weeks. The BFR-W group wore pressure cuffs on both legs during training. Maximum knee joint strength (similar to 15%) and MRI-measured thigh muscle cross-sectional area (3%) increased in the BFR-W, but not in the CON-W. Carotid arterial compliance improved in both BFR-W (50%) and CON-W (59%) groups. Walk training with blood flow reduction can improve thigh muscle size/strength as well as carotid arterial compliance, unlike high-intensity training, in the elderly.

Objective: To evaluate exercise intervention efficacy for the prevention and treatment of sarcopenia in the elderly. Methods: We conducted a systematic literature search of randomized controlled trials in the Physical Activity Guidelines Advisory Committee Report (before 2007), Pubmed, the Cochrane database, and Igaku Chuo Zasshi (January 2006 to August 2009) Data Extraction: Two authors independently extracted relevant data. A total of 951 articles were found by search engines, and 9 studies were finally selected after a review by 2 experts. The content of these studies, especially duration, sets, periods, frequency, and intensity of exercise intervention were extracted and summarized in a results table. Five of 6 articles concluded that high-intensity resistance training significantly increased soft lean tissue and muscle mass. The remaining 3 articles indicated that moderate-intensity resistance training did not affect soft lean tissue or muscle mass. Conclusion: This systematic review suggested that high-intensity resistance training with sufficient periods, frequency, repetitions, and sets is effective to counteract the loss of muscle mass associated with advancing age.

サルコペニアの代替指標である骨格筋量に対する運動介入研究を検索し、サルコペニアの予防・改善のための適切な運動方法について検討した。一次検索により951本の論文が抽出され、うち選定された9論文を対象とした。5本は高強度筋力トレーニングが高齢者の骨格筋量を増加させるとしたものであった。3本は低・中強度筋力トレーニングは骨格筋に影響しないというものであった。骨格筋量を増加させるためには、最大挙上重量(1RM)の80%以上の強度で、1セット当たりの挙上回数が8〜12回の運動を2〜3セット、週3回、3ヵ月以上行う高強度筋力トレーニングを行う必要があることが示唆された

Objective: The aim of this study was to evaluate aerobic exercise levels, expressed in terms of ventilatory threshold (VT), in a Japanese population and explore the relationship between VT and exercise habits in this population. Methods: This was a cross-sectional study in which data collected from 547 men and 524 women aged 20-69 years and not on medications, were used to assess exercise habits and parameters at VT, namely, oxygen uptake, work rate, and heart rate. Results: Age-related changes in parameters at VT were noted. Of the participants, 205 men (37.5%) and 142 women (27.1%) had exercise habits. Oxygen uptake and work rate at VT in subjects with exercise habits were significantly higher than those without exercise habits after age had been adjusted for in both sexes. Anthropometric parameters were significantly correlated with oxygen uptake at VT, and the highest correlation coefficient rate was found between oxygen uptake at VT and body fat percentage (men r = -0.589, women r = -0.631). Conclusion: The mean values determined here may provide a useful database for evaluating VT in Japanese adult subjects. © 2010 The Japanese Society for Hygiene.

Greater venous compliance is associated with attenuation of the tolerance response to orthostatic stress and reduced incidence of venous diseases. Resistance training induces tolerance to orthostatic challenge and the growth of capillaries, which may lead to negative and positive effects on venous compliance, respectively. It has not been confirmed, however, whether habitual resistance training positively or negatively affects venous compliance. We compared the forearm venous compliance in resistance-trained men with age-matched controls. Eleven resistance-trained middle-aged men (37.7 +/- A 1.5 years) and 12 age-matched sedentary controls (36.7 +/- A 1.6 years) were studied. Forearm venous compliance was measured in subjects in the supine position by inflating a venous collecting cuff placed around the upper arm to 60 mmHg for 8 min and then decreasing cuff pressure to 0 mmHg at a rate of 1 mmHg/s. Forearm venous compliance was determined using the first derivative of the pressure-volume relation during cuff pressure reduction (compliance = beta(1) + 2 beta(2) x cuff pressure). Forearm venous compliance at 20 mmHg cuff pressure was 16% greater in the resistance-trained group than in the age-matched sedentary controls (0.097 +/- A 0.005 vs. 0.083 +/- A 0.004 ml/dl/mmHg, P &lt; 0.05). Forearm venous compliance was positively related to forearm venous volume (r = 0.643, P = 0.0009), but not forearm muscle mass (r = 0.391, P = 0.0648). In conclusion, the present study suggests that (1) the resistance-trained men have greater forearm venous compliance than age-matched controls, and (2) the higher forearm venous compliance in the resistance-trained men may be explained by greater forearm venous capacitance.

In this study of Japanese men and women, we determine reference values for sarcopenia and test the hypothesis that sarcopenia is associated with risk factors for cardiovascular disease, independent of waist circumference. A total of 1,488 Japanese men and women aged 18-85 years participated in this study. Appendicular muscle mass (AMM) was measured by dual-energy X-ray absorptiometry. Reference values for classes 1 and 2 sarcopenia (skeletal muscle index: AMM/height(2), kg m(-2)) in each sex were defined as values one and two standard deviations below the sex-specific means of reference values obtained in this study from young adults aged 18-40 years. The reference values for class 1 and class 2 sarcopenia were 7.77 and 6.87 kg m(-2) in men and 6.12 and 5.46 kg m(-2) in women. In subjects both with class 1 and class 2 sarcopenia, body mass index and % body fat were significantly lower than in normal subjects. Despite whole-blood glycohaemoglobin A1c in men with class 1 sarcopenia was significantly higher than in normal subjects, and brachial-ankle pulse wave velocity in women both with class 1 and class 2 sarcopenia were significantly higher than in normal subjects, using one-way ANCOVA with adjustment for the covariate of waist circumference. Although sarcopenia is associated with thin body mass, it is associated with more glycation of serum proteins in men and with greater arterial stiffness in women, independent of waist circumference.

Habitual moderate-to-vigorous-intensity physical activity attenuates arterial stiffening. However, it is unclear whether light physical activity also attenuates arterial stiffening. It is also unclear whether light physical activity has the same effects in fit and unfit individuals. This cross-sectional study was performed to determine the relationships between amount of light physical activity determined with a triaxial accelerometer and arterial stiffness. A total of 538 healthy men and women participated in this study. Subjects in each age category were divided into either high-light or low-light physical activity groups based on daily time spent in light physical activity. Arterial stiffness was measured by carotid-femoral pulse wave velocity. Two-way ANOVA indicated a significant interaction between age and time spent in light physical activity in determining carotid-femoral pulse wave velocity (P&lt;0.05). In the older group, carotid femoral pulse wave velocity was higher in the low-light physical activity level group than in the high-light physical activity level group (945 +/- 19 versus 882 +/- 16 cm/s; P&lt;0.01). The difference remained significant after normalizing carotid-femoral pulse wave velocity for amounts of moderate and vigorous physical activity. The carotid-femoral pulse wave velocity (r=-0.47; P&lt;0.01) was correlated with daily time spent in light physical activity in older unfit subjects. No relationship was observed in older fit subjects. These results suggested that longer time spent in light physical activity is associated with attenuation of arterial stiffening, especially in unfit older people. (Hypertension. 2010;56:540-546.)

Iemitsu M, Murakami H, Sanada K, Yamamoto K, Kawano H, Gando Y, Miyachi M. Lack of carotid stiffening associated with MTHFR 677TT genotype in cardiorespiratory fit adults. Physiol Genomics 42: 259-265, 2010. First published April 20, 2010; doi: 10.1152/physiolgenomics.00039.2010.-The TT genotype of C677T polymorphism in 5,10-methylenetetrahydrofolate reductase (MTHFR) induces elevation of homocysteine level and leads to atherosclerosis and arterial stiffening. Furthermore, cardiorespiratory fitness level is also associated with arterial stiffness. In the present study, a cross-sectional investigation of 763 Japanese men and women (18-70 yr old) was performed to clarify the effects of cardiorespiratory fitness on the relationship between arterial stiffness and MTHFR C677T gene polymorphism. Arterial stiffness was assessed by carotid beta-stiffness with ultrasonography and tonometry. The study subjects were divided into high-cardiorespiratory fitness (High-Fit) and low-cardiorespiratory fitness (Low-Fit) groups based on the median value of peak oxygen uptake in each sex and decade. The plasma homocysteine level was higher in the TT genotype of MTHFR C677T polymorphism compared with CC and CT genotype individuals. MTHFR C677T polymorphism showed no effect on carotid beta-stiffness, but there was a significant interaction effect between fitness and MTHFR C677T polymorphism on carotid beta-stiffness (P = 0.0017). In the Low-Fit subjects, carotid beta-stiffness was significantly higher in individuals with the TT genotype than the CC and CT genotypes. However, there were no such differences in High-Fit subjects. In addition, beta-stiffness and plasma homocysteine levels were positively correlated in Low-Fit subjects with the TT genotype (r = 0.71, P &lt; 0.0001), but no such correlations were observed in High-Fit subjects. In CC and CT genotype individuals, there were also no such correlations in either fitness level. These results suggest that the higher cardiorespiratory fitness may attenuate central artery stiffening associated with MTHFR C677T polymorphism.

MIYACHI, M., K. YAMAMOTO, K. OHKAWARA, and S. TANAKA. METs in Adults While Playing Active Video Games: A Metabolic Chamber Study. Med. Sci. Sports Exerc., Vol. 42, No. 6, pp. 1149-1153, 2010. Purpose: Active video game systems controlled through arm gestures and motions (Nintendo Wii Sports) and video games controlled through force plate (Wii Fit Plus) are becoming increasingly popular. This study was performed to determine the energy expenditure (EE) during Wii Fit Plus and Wii Sports game activities. Methods: Twelve adult men and women performed all the activities of Wii Sports (five activities: golf, bowling, tennis, baseball, and boxing) and Wii Fit Plus (63 activities classified as yoga, resistance, balance, and aerobic exercises). Each activity was continued for at least 8 min to obtain a steady-state EE. Because EE was assessed in an open-circuit indirect metabolic chamber consisting of an airtight room (20,000 or 15,000 L), subjects were freed of apparatus to collect expired gas while playing the games. MET value was calculated from resting EE and steady-state EE during activity. Results: The mean MET values of all 68 activities were distributed over a wide range from 1.3 METs (Lotus Focus) to 5.6 METs (single-arm stand). The mean MET values in yoga, balance, resistance, and aerobic exercise of Wii Fit Plus and Wii Sports were 2.1, 2.0, 3.2, 3.4, and 3.0 METs, respectively. Forty-six activities (67%) were classified as light intensity (&lt;3 METs), and 22 activities (33%) were classified as moderate intensity (3.0-6.0 METs). There were no vigorous-intensity activities (&gt;6.0 METs). Conclusions: Time spent playing one-third of the activities supplied by motion-and gesture-controlled video games can count toward the daily amount of exercise required according to the guidelines provided by the American College of Sports Medicine and the American Heart Association, which focus on 30 min of moderate-intensity daily physical activity 5 d.wk(-1).

The present study investigated the use of the accelerometer-determined physical activity (PA) variables as the objective PA variables for estimating V̇O2max in Japanese adult men. One hundred and twenty-seven Japanese adult men aged from 20 to 69 years were recruited as subjects of the present study. Maximal oxygen uptake (V̇O2max) was measured with a maximal incremental test on a bicycle ergometer. Daily step counts (SC) and the amount spent in moderate to vigorous PA (MVPA) and vigorous PA (VPA) were measured using accelerometer-based activity monitors worn at the waist for seven consecutive days. The non-exercise models were derived using hierarchical linear regression analysis, and cross-validated using two separate cross-validation procedures. SC, MVPA, and VPA were significantly related to V̇O2max (partial correlation coefficient r = 0.58, r = 0.42, and r = 0.51, respectively) after adjusting for age. Two models were developed by multiple regression to estimate V̇O2max using data of age, SC, VPA, and either BMI (the coefficient of determination (R2) = 0.71, standard error of estimate (SEE) = 4.2 ml kg-1 min-1), or waist circumference (R2 = 0.74, SEE = 3.9 ml kg-1 min -1). All regression models demonstrated a high level of cross-validity supported by the minor shrinkage of R2 and increment of SEE in the PRESS procedure, and by small constant errors for subgroups of age, SC, and V̇O2max: This study demonstrated that combining SC with VPA, but not with MVPA, was useful in predicting V̇O2max variance and improved the ability of the regression models to accurately predict V̇O2max. © Springer-Verlag 2010.

Arterial stiffening, hypertension and left ventricular (LV) remodelling are associated with increased risk of cardiovascular disease. Cardiorespiratory fitness is associated with cardiovascular function and reduced risk of cardiovascular disease. This cross-sectional study was carried out to determine the relationships between cardiorespiratory fitness, arterial stiffness, blood pressure (BP) and LV remodelling in women. On the basis of peak oxygen uptake, a total of 159 premenopausal (young) and postmenopausal (older) women were categorized into either low (unfit) or high (fit) cardiorespiratory fitness groups. The arterial stiffness and LV remodelling were measured by brachial-ankle pulse wave velocity (baPWV) and carotid augmentation index (AI) and LV relative wall thickness (RWT). Two-way analysis of variance indicated a significant interaction between age and cardiorespiratory fitness in baPWV, carotid AI, BP and RWT. In the older group, arterial stiffness (baPWV; 1401 +/- 231 vs 1250 +/- 125cms(-1), P&lt;0.01, AI; 32.9 +/- 9.9 vs 24.8 +/- 10.1%, P&lt;0.01), systolic blood pressure (SBP) (130 +/- 22 vs 117 +/- 15mmHg, P&lt;0.01) and RWT (0.47 +/- 0.08 vs 0.42 +/- 0.04, P&lt;0.05) in fit women were lower than in unfit women. In older women, RWT was significantly related to baPWV (r = 0.46, P&lt;0.01), carotid AI (r = 0.29, P&lt;0.05), SBP (r = 0.57, P&lt;0.01). (V) over dot(2peak) (r = -0.32, P&lt;0.05). In young women, they were not significant correlations, except for a weak correlation between RWT and SBP (r = 0.21, P&lt;0.05). These results suggest that higher cardiorespiratory fitness is associated with lower arterial stiffness, BP and RWT in older women. Journal of Human Hypertension (2010) 24, 197-206; doi:10.1038/jhh.2009.57; published online 16 July 2009

This study aimed to determine the validity of a standard questionnaire to assess amount of physical activity (PA) and cardiorespiratory fitness (VO2peak). A total of 483 men and women, aged 20 to 69 years, participated. The standard questionnaire included 3 items about exercise, PA, and walking speed. All questions were designed to require an answer of Yes or No. Subjects were classified into one of four groups regarding the number of Yes answers to the three questions, giving activity levels of 0 to 3. The amount of PA was measured objectively with a tn-axial accelerometer which could also calculate daily step counts, and the amounts of PA under 3 metabolic equivalents (METs) and at 3 METs or more. VO2peak. was measured by incremental cycle exercise tests with indirect calorimetry. The daily step counts, the amount of PA at 3 METs or more, and the VO2peak. were significantly higher in subjects who answered Yes to each question than in those who answered No. Sensitivity and specificity of each question were 62-73% and 45-71% for the amount of PA established with the &quot;Exercise and Physical Activity Reference for Health Promotion 2006 (EPAR2006)&quot;. The sum of sensitivity and specificity was the highest when the cutoff value was activity level 2 (sensitivity 73%, specificity 68%). Sensitivity and specificity for VO2max established by EPAR2006 were lower than those for the amount of PA. These results suggest that only answering simple questions with a standard questionnaire is sufficient for estimation of PA levels for specific medical checkups and health guidance, even though the accuracy is somewhat limited.

The purpose of this study was to develop prediction models of sarcopenia in 1,894 Japanese men and women aged 18-85 years. Reference values for sarcopenia (skeletal muscle index, SMI; appendicular muscle mass/height , kg/m2) in each sex were defined as values two standard deviations (2SD) below the gender-specific means of this study reference data for young adults aged 18-40 years. Reference values for predisposition to sarcopenia (PSa) in each gender were also defined as values one standard deviations (1SD) below. The subjects aged 41 years or older were randomly separated into 2 groups, a model development group and a validation group. Appendicular muscle mass was measured by DXA. The reference values of sarcopenia were 6.87 kg/m2 and 5.46 kg/nf, and those of PSa were 7.77 kg/m2 and 6.12 kg/m8. The subjects with sarcopenia and PSa aged 41 years or older were 1.7% and 28.8% in men and 2.7% and 20.7% in women. The whole body bone mineral density of PSa was significantly lower than in normal subjects. The handgrip strength of PSa was significantly lower than in normal subjects. Stepwise regression analysis indicated that the body mass index (BMI), waist circumference and age were independently associated with SMI in men; and BMI, handgrip strength and waist circumference were independently associated with SMI in women. The SMI prediction equations were applied to the validation group, and strong correlations were also observed between the DXA-measured and predicted SMI in men and women. This study proposed the reference values of sarcopenia in Japanese men and women. The prediction models of SMI using anthropometric measurement are valid for alternative DXA-measured SMI in Japanese adults.

PURPOSE: To investigate the use of the accelerometer-determined physical activity (PA) intensity variables as the objective PA variables for estimating V̇O2max in Japanese adult women. METHODS: The subjects of this study were 148 Japanese women aged 20 to 69 yr. Maximal oxygen uptake (V̇O2max) was measured with a maximal incremental test on a bicycle ergometer. Daily step counts (SC) and the amount spent in moderate to vigorous PA (MVPA) and vigorous PA (VPA) were measured using accelerometer-based activity monitors for 7 consecutive days. Using data of age, SC, MVPA, or VPA, and either body mass index (BMI) or waist circumference (WC), the nonexercise V̇O2max prediction models were derived as BMI models, WC models, BMI models, and WC models, and cross-validated by using two separate cross-validation procedures. RESULTS: SC, MVPA, and VPA were significantly related to V̇O2max (r = 0.43, r = 0.52, and r = 0.58, respectively). The multiple correlation coefficients for the BMI and WC models were 0.83 and 0.85, respectively, and for the BMI and WC models, they were 0.85 and 0.86, respectively. The SEE was 3.3 and 3.1 mL•kg•min for the BMI and WC models, respectively, and it was 3.1 and 3.0 mL•kg•min for the BMI and WC models, respectively. All regression models demonstrated a high level of cross-validity supported by the minor shrinkage of the coefficient of determination and the increment of SEE in the predicted residual sum of squares procedure, and by small constant errors for the subgroups of age, SC, and V̇O2max between 25 and 35 mL•kg•min. CONCLUSIONS: This study demonstrated that multiple regression models using data of MVPA or VPA were useful in predicting V̇O2max for Japanese adult women. Copyright © 2009 by the American College of Sports Medicine.

Objective Changes in metabolic syndrome and its components with lifestyle modification were evaluated in Japanese men.
Methods We used data for 160 Japanese men (45.6 +/- 8.8 years) with a 1-year follow up. Anthropometric, blood examination and blood pressure measurements were evaluated. Metabolic syndrome was defined by using a criterion in Japan. All subjects were given instructions by well-trained medical staff on how to change their lifestyle.
Results With a 1-year follow-up, anthropometric parameters, blood pressure (BP), triglyceride and HDL cholesterol were significantly improved and the prevalence of metabolic syndrome was significantly reduced. The number of subjects with abdominal obesity at baseline and at follow-up was higher (81 men) than that of subjects with other components at baseline and at follow-up. Parameters at baseline were significantly correlated with changes in parameters for one year. With lifestyle modification, the level of 163 mmHg in systolic BP (SBP), 115 mmHg in diastolic BP (DBP), 226 mg/dL in triglyceride and 33 mg/dL in HDL cholesterol at baseline was estimated to improve to the level without medications with a 1-year follow up.
Conclusion Lifestyle modification is useful for improving metabolic syndrome and its components. However, items of metabolic syndrome were improved, even when the abdominal circumference was greater than the normal value for Japanese men.

保健指導における運動中止者の阻害要因について、全国の保健指導プログラムの企画・実施者の成果報告分析および運動指導を含む保健指導プログラム参加者を対象とした調査結果から検討した。その結果、運動効果が実感できない、運動に対する自己効力感(セルフエフィカシー)をもてない、家族・職場上司・地域などの理解や支援がないの3要因をプログラムから排除することが重要であった。以上より、保健指導における脱落を抑制し継続を促すためには、脱落せず最後までプログラムに参加できれば効果が実感でき、自信も湧いてきて、周囲の理解も高まっていくとの考えから脱落を予防するためのチェックシートおよび運動継続を促す循環モデルを呈示した。

Reduced response to reactive hyperemia (RH) in the extremities reflects impaired endothelium-dependent vasodilation of the microvasculature. The aims of the present study were to determine whether resistance training and a combination of aerobic and resistance training increase the endothelial vasodilation of the forearm assessed by RH. A total of 39 young men were assigned to either high-intensity resistance training (HIR; six types of exercises, 80% 1RM x 10 repetitions x 3 sets, n = 14) or moderate-intensity resistance training (MIR; six types of exercises, 50% 1RM x 16 repetitions x 3 sets, n = 14) or a combination of high-intensity resistance training and moderate-intensity endurance training (COMBO; HIR and 60% maximal heart rate x 30 min, n = 11) groups. We measured forearm blood flow response to RH before and after 4 months of exercise intervention. All training groups increased maximal strength in all muscle groups tested (all P &lt; 0.05). After 4 months of training, the forearm blood flow during RH increased significantly in the MIR and COMBO groups, from 57 +/- 4 to 66 +/- 7 ml/min per 100 ml tissue and from 59 +/- 6 to 74 +/- 8 ml/min per 100 ml tissue, respectively (both P &lt; 0.05). There was no change in the response to RH in the HIR groups. In conclusion, the findings in this study demonstrate that combined resistance and aerobic training may affect the vasoreactivity response to RH in the forearm, but not resistance training alone.

Tanimoto M, Arakawa H, Sanada K, Miyachi M, and Ishii N. Changes in muscle activation and force generation patterns during cycling movements because of low-intensity squat training with slow movement and tonic force generation. J Strength Cond Res 23( 8): 2367-2376, 2009-Our previous studies showed that relatively low-load (similar to 50-60% 1 repetition maximum [1RM]) resistance training with slow movement and tonic force generation (LST) significantly increased muscle size and strength. However, LST is a very specific movement that differs from natural movements associated with sport activities and activities of daily life, and therefore, it might have some unfavorable effects on dynamic sport movement. We investigated the effects of LST on muscle activity and force generation patterns during cycling movement as a representative dynamic sports movement. Twenty-four healthy young men who were not in the habit of bicycle riding and did not have a history of regular resistance training were randomly assigned to the LST (similar to 60% 1RM load, 3-second lifting, and 3-second lowering movement without a relaxing phase: n = 8), a high-intensity exercise at normal speed (HM) group (85% 1RM load, 1-second lifting, 1-second lowering, and 1-second relaxed movement: n = 8), or sedentary control (CON, n = 8) group. Subjects in the training groups performed vertical squats by the assigned method. Exercise sessions consisted of 3 sets and were performed twice a week for 13 weeks. Pre- and posttraining muscle activation and force generation patterns during the cycling movements were evaluated by the coefficient of variation (CV) of the rectified electromyographic (EMG) wave from the vastus lateralis and CV of pedaling force. Both the CV of the rectified EMG and of pedaling force decreased significantly in the LST group (221 and 218%, p &lt; 0.05, respectively), whereas there were no significant changes in either the HN or the CON group. This decrease in CV in the LST group could mean that muscle activity and force generation during cycling movement have become more tonic. This result following LST may have an unfavorable effect on cycling movement and other dynamic sports movements.

Yamamoto K, Kawano H, Gando Y, Iemitsu M, Murakami H, Sanada K, Tanimoto M, Ohmori Y, Higuchi M, Tabata I, Miyachi M. Poor trunk flexibility is associated with arterial stiffening. Am J Physiol Heart Circ Physiol 297: H1314-H1318, 2009. First published August 7, 2009; doi: 10.1152/ajpheart.00061.2009.-Flexibility is one of the components of physical fitness as well as cardiorespiratory fitness and muscular strength and endurance. Flexibility has long been considered a major component in the preventive treatment of musculotendinous strains. The present study investigated a new aspect of flexibility. Using a cross-sectional study design, we tested the hypothesis that a less flexible body would have arterial stiffening. A total of 526 adults, 20 to 39 yr of age (young), 40 to 59 yr of age (middle-aged), and 60 to 83 yr of age ( older), participated in this study. Subjects in each age category were divided into either poor- or high-flexibility groups on the basis of a sit-and-reach test. Arterial stiffness was assessed by brachial-ankle pulse wave velocity (baPWV). Two-way ANOVA indicated a significant interaction between age and flexibility in determining baPWV (P &lt; 0.01). In middle-aged and older subjects, baPWV was higher in poor- flexibility than in high-flexibility groups (middle-aged, 1,260 +/- 141 vs. 1,200 +/- 124 cm/s, P &lt; 0.01; and older, 1,485 +/- 224 vs. 1,384 +/- 199 cm/s, P &lt; 0.01). In young subjects, there was no significant difference between the two flexibility groups. A stepwise multiple-regression analysis (n = 316) revealed that among the components of fitness (cardiorespiratory fitness, muscular strength, and flexibility) and age, all components and age were independent correlates of baPWV. These findings suggest that flexibility may be a predictor of arterial stiffening, independent of other components of fitness.

The aim of this study was to explore muscle strength and its relation to exercise habits in Japanese. We used data from 3,018 men and 6,881 women aged 20-69 years and not using medications in a cross-sectional study. Exercise habits and muscle strength, i.e. grip strength and leg strength, were measured. Age-related changes in muscle strength were noted. Exercise habits were found in 984 men (32.6%) and 1,664 women (24.2%). For subjects of both sexes over 50 years, grip strength was significantly decreased with age. However, the ratio of leg strength to body weight significantly decreased with age as early as 30 years in men and 40 years in women. Grip strength, leg strength and the ratio of leg strength to body weight in subjects with exercise habits were significantly higher than those without exercise habits after adjusting for age in both sexes. This standard mean value may provide a useful database for evaluating muscle strength in Japanese adult subjects. Copyright © 2009 by Okayama University Medical School.

Metabolic syndrome is associated with reductions in basal limb blood flow. Resistance training increasing muscle mass and strength increases basal limb blood flow. Low-intensity resistance exercise with slow movement and tonic force generation (LST) has been proposed as one of the effective methods of resistance training increasing muscle mass and strength. The hypothesis that LST training increases basal femoral blood flow as well as traditional high-intensity resistance training at normal speed (HN) was examined. Thirty-six healthy young men without a history of regular resistance training were randomly assigned to the LST [similar to 55-60% one repetition maximum (1RM) load, 3 s lifting and 3 s lowering with no relaxation phase, n = 12], HN (similar to 85-90% 1RM, 1 s lifting and 1 s lowering with 1 s relaxation, n = 12) or sedentary control (CON, n = 12) groups. Participants in the training groups underwent two whole-body training sessions per week for 13 weeks. Basal femoral blood flow increased significantly by +18% in LST and +35% in HN (both P &lt; 0.05), while there was no such change in CON. There were no significant differences between these increases induced by LST and HN, although the increase in LST corresponded to about half that in HN. In conclusion, not only resistance training in HN but in LST as well, were effective for increasing basal limb blood flow, and that this effect was evident even in healthy young men.

Objective: To evaluate the possibility that measurement of the magnitude and distribution of fundamental somatic heat-producing units using dual-energy X-ray absorptiometry (DXA) can be used to estimate resting energy expenditure (REE) in both young and elderly women with different aerobic fitness levels.
Subjects and methods: Peak oxygen uptake (VO(2) peak) and REE(m) were directly measured in 116 young (age: 22.3 +/- 2.1 years) and 72 elderly (63.3 +/- 6.4 years) women. The subjects were divided into four groups according to categories of age and VO(2) peak; young: high fitness (YH, n = 58); low fitness (YL, n = 58); elderly: high fitness (EH, n = 37) and low fitness (EL, n = 35). Using DXA, systemic and regional body compositions were measured, and REE(e) was estimated from the sum of tissue organ weights multiplied by corresponding metabolic rate.
Results: Although there were remarkable differences in systemic and regional body compositions, no significant differences were observed between REE(m) and REE(e) in the four groups. REE(e) significantly correlated with REE(m) in elderly as well as young women; the slopes and intercepts of the two regression lines were statistically not different between the elderly and young groups (elderly: y = 0.60x+472, r = 0.667; young: y = 0.78x+250, r = 0.798; P &lt; 0.001, respectively). A Bland-Altman analysis did not indicate bias in calculation of REE for all the subjects.
Conclusion: These results suggest that REE can be estimated from tissue organ components in women regardless of age and aerobic fitness.

Objective: To investigate the relationships between regional skeletal muscle mass (SM mass) and bone mineral indices and to examine whether bone mineral content (BMC) normalized to SM mass shows a similar decrease with age in young through old age.
Subjects/Methods: One hundred and thirty-eight young and postmenopausal women aged 20-76 years participated in this study and were divided into three groups: 61 young women, 49 middle-aged postmenopausal women and 28 older postmenopausal women. Muscle thickness (MTH) was determined by ultrasound, and regional SM mass (arm, trunk and leg) was estimated based on nine sites of MTH. Whole-body and regional lean soft tissue mass (LSTM), bone mineral density (BMD) and BMC (whole body, arms, legs and lumbar spine) were measured using dual-energy X-ray absorptiometry.
Results: Ultrasound spectroscopy indicated that SM mass is significantly correlated with site-matched regional bone mineral indices and these relationships correspond to LSTM. The BMC and BMD in older women were significantly lower than those in middle-aged women. When BMC was normalized to site-matched regional SM mass, BMC normalized to SM mass in arm and trunk region were significantly different with age; however, whole-body and leg BMC normalized to SM mass showed no significant difference between middle-aged and older postmenopausal women.
Conclusions: The age-related differences in BMC were found to be independent of the ageing of SM mass in the arm and trunk region. However, differences in BMC measures of the leg and whole body were found to correspond to age-related decline of SM mass in postmenopausal women.

Background/Objective: The most significant complication and leading cause of death for people with spinal cord injury (SCI) is coronary artery disease (CAD). It has been confirmed that aortic pulse wave velocity (PVW) is an emerging CAD predictor among able-bodied individuals. No prior study has described PWV values among people with SCI. The objective of this study was to compare aortic (the common carotid to femoral artery) PVW, arm (the brachial to radial artery) PWV, and leg (the femoral to posterior tibial artery) PVW in people with SCI (SCI group) to able-bodied controls (non-SCI group). Methods: Participants included 12 men with SCI and 9 non-SCI controls matched for age, sex, height, and weight. Participants with a history of CAD or current metabolic syndrome were excluded. Aortic, arm, and leg PWV was measured using the echo Doppler method. Results: Aortic PVW (mean ± SID) in the SCI group (1,274 ± 369 cm/s) was significantly higher (P &lt
0.05) than in the non-SCI group (948 ± 110 cm/s). There were no significant between-group differences in mean arm PWV (SCI: 1,152 ± 193 cm/s, non-SCI: 1,237 ± 193 cm/s) or mean leg PWV (SCI: 1,096 ± 173 cm/s, non-SCI: 994 ± 178 cm/s) values. Conclusions: Aortic PWV was higher among the SCI group compared with the non-SCI group. The higher mean aortic PWV values among the SCI group compared with the non-SCI group indicated a higher risk of CAD among people with SCI in the absence of metabolic syndrome. © 2009 by the American Paraplegia Society.

The purpose of the study was to develop a new non-exercise VO(2max) prediction model using a physical activity (PA) variable determined by pedometer-determined step counts (SC, steps day(-1)) in Japanese women aged 20-69 years old. Eighty-seven and 102 subjects were used to develop the prediction model, and to validate the new model, respectively. VO(2max) was measured using a maximal incremental test on a bicycle ergometer. SC was significantly related to VO(2max) (partial correlation coefficient r = 0.40, P &lt; 0.001) after adjusting for BMI (kg m(-2)) and age (years). When the new prediction equation developed by multiple regression to estimate VO(2max) from age, BMI, and SC (R = 0.71, SEE = 5.3 ml kg(-1) min(-1), P &lt; 0.001) was applied to the Validation group, predicted VO(2max) correlated well with measured VO(2max) (r = 0.81, P &lt; 0.001), suggesting that SC is a useful PA variable for non-exercise prediction of VO(2max) in Japanese women.

It has been reported that treatment with a pharmacological dose (45 mg/ d) of menaquinone-4 (MK-4) prevents bone loss in postmenopausal women. However, it is not known whether supplementation with low dose MK-4 has beneficial effects on bone metabolism in healthy women. The aim of this study is to examine the effects of the supplementation of 1.5 mg/d MK-4 for 4 wk on bone and lipid metabolism in healthy postmenopausal Japanese women. The study was performed as a randomized double blind placebo-controlled trial. The participants aged 53-65 y were randomly assigned to 2 groups and supplemented with 1.5 mg/d of MK-4 or a placebo for 4 wk (n=20 for each group). The most marked effects of MK-4 intake were observed on serum osteocalcin (OC) concentrations. Serum undercarboxylated OC (ucOC) concentration decreased, and the γ-carboxylated OC (GlaOC) and GlaOC/GlaOC+ucOC ratio that indicates the degree of OC γ-carboxylation increased significantly at 2 and 4 wk compared with that at baseline in the MK-4 group. The serum ucOC and GlaOC concentrations in the MK-4 group were significantly different from those in the placebo group at 2 wk. These results suggest that supplementation with 1.5 mg/d MK-4 accelerated the degree of OC γ-carboxylation. The concentrations of serum lipids and other indices were not different between the groups at either intervention period. Thus, the additional intake of MK-4 might be beneficial in the maintenance of bone health in post-menopausal Japanese women.

The aim of this cross-sectional study was to compare body composition and risk factors of lifestyle-related diseases between young and older male rowers and sedentary controls. Healthy males aged 19-73 years participated in the study, and were divided into four groups: 26 young rowers, 24 senior rowers, 23 young sedentary controls, and 22 senior sedentary controls. Total and regional lean soft tissue, fat mass, and bone mineral density were measured using dual-energy X-ray absorptiometry. The HDL-cholesterol of senior rowers (67.4 +/- 13.4 mg . dl(-1)) was significantly (P &lt; 0.05) higher than that of senior sedentary controls (59.2 +/- 11.9 mg . dl(-1)), while HDL-cholesterol was similar in senior rowers and young rowers (66.1 +/- 10.8 mg . dl(-1)). Arm, leg, and trunk lean soft tissue mass were significantly higher in senior rowers (5.6 +/- 0.6 kg, 18.2 +/- 1.8 kg, and 27.3 +/- 3.2 kg respectively) than in senior sedentary controls (5.1 +/- 0.4 kg, 16.3 +/- 1.4 kg, and 24.6 +/- 1.7 kg respectively; P &lt; 0.05). Bone mineral density was also significantly higher in senior rowers than in senior sedentary controls (ribs, lumbar spine, and pelvic segments; P &lt; 0.05). We conclude that age-related increases in the risk of lifestyle-related diseases, such as osteoporosis and sarcopenia, are attenuated in male rowers. These results suggest that regular rowing exercise may have a positive influence in the prevention of lifestyle-related diseases in older Japanese people.

Tanimoto, M, Sanada, K, Yamamoto, K, Kawano, H, Gando, Y, Tabata, I, Ishii, N, and Miyachi, M. Effects of whole-body low-intensity resistance training with slow movement and tonic force generation on muscular size and strength in young men. J Strength Cond Res 22(6): 1926-1938, 2008-Our previous study showed that relatively low-intensity (similar to 50% one-repetition maximum [1RM]) resistance training (knee extension) with slow movement and tonic force generation (LST) caused as significant an increase in muscular size and strength as high-intensity (similar to 80% 1RM) resistance training with normal speed (HN). However, that study examined only local effects of one type of exercise (knee extension) on knee extensor muscles. The present study was performed to examine whether a whole-body LST resistance training regimen is as effective on muscular hypertrophy and strength gain as HN resistance training. Thirty-six healthy young men without experience of regular resistance training were assigned into three groups (each n = 12) and performed whole-body resistance training regimens comprising five types of exercise (vertical squat, chest press, latissimus dorsi pull-down, abdominal bend, and back extension: three sets each) with LST (similar to 55-60% 1RM, 3 seconds for eccentric and concentric actions, and no relaxing phase); HN (similar to 80-90% 1RM, 1 second for concentric and eccentric actions, 1 second for relaxing); and a sedentary control group (CON). The mean repetition maximum was eight-repetition maximum in LST and HN. The training session was performed twice a week for 13 weeks. The LST training caused significant (p &lt; 0.05) increases in whole-body muscle thickness (6.8 +/- 3.4% in a sum of six sites) and 1RM strength (33.0 +/- 8.8% in a sum of five exercises) comparable with those induced by HN training (9.1 +/- 4.2%, 41.2 +/- 7.6% in each measurement item). There were no such changes in the CON group. The results suggest that a whole-body LST resistance training regimen is as effective for muscular hypertrophy and strength gain as HN resistance training.

Background: Since it is essential to maintain a high level of cardiorespiratory fitness to prevent life-style related disease, the Ministry of Health, Labour and Welfare of Japan in 2006 proposed to determine the maximal oxygen uptake (Vo(2)max: mL . kg(-1) . min(-1)) reference values to prevent lifestyle related diseases (LSRD). Since muscle mass is one of the determinant factors of Vo(2)max, it could be used as the reference parameter for preventing LSRD. The aim of this study was to determine and quantify the muscle mass required to maintain the Vo2max reference values in Japanese women.
Methods: A total of 403 Japanese women aged 20-69 years were randomly allocated to either a validation or a cross-validation group. In the validation group, a multiple regression equation, which used a set of age and the percentage of muscle mass (%MM, percentage of appendicular lean soft tissue mass to body weight), as independent variables, was derived to estimate the Vo(2)max. After the equation was cross-validated, data from the two groups were pooled together to establish the final equation. The required %MM for each subject was recalculated by substituting the Vo(2)max reference values and her age in the final equation.
Results: The mean value of required %MM was identified as (28.5 +/- 0.35%). Thus, the present study proposed the required muscle mass (28.5% per body weight) in Japanese women to maintain the Vo(2)max reference values determined by the Japanese Ministry of Health Labour and Welfare.
Conclusion: The estimated required %MM (28.5% per body weight) can be used as one of the reference parameters of fitness level in Japanese women.

The present study was performed to test the hypothesis that the blood pressure (BP) response to resistance exercise in middle-aged men with stiffening arteries is greater than that in young men with compliant arteries. The BP responses to acute dynamic resistance exercise (leg press) at individual relative (low, moderate and high) and absolute intensities were investigated in both young and middle-aged men. A total of 21 sedentary healthy normotensive men, 21-25 years of age (young) and 41-59 years of age (middle-aged), were included in the study. At rest, the arterial compliance (simultaneous ultrasound and applanation tonometry) and muscle strength (leg press) were lower, and indices of arterial stiffness and BP were higher in the middle-aged men than in the young men (p &lt; 0.05). There were no significant differences in height, body mass, or heart rate between the two groups. During exercise, the systolic BP of the middle-aged men at 80% one-repetition maximum (1RM) was significantly lower than that of the young men for the last half of the exercise period (p &lt; 0.05). The amounts of change in systolic and diastolic BP from baseline to the end of resistance exercise were lower in the middle-aged men than in the young men at individual relative intensities (p &lt; 0.05) and at individual absolute intensity. In contrast to our hypothesis, these findings indicated that the BP response during dynamic resistance exercise using large muscle groups may be attenuated in middle-aged men relative to young men.

Resistance training is a popular mode of exercise, but may result in stiffening of the central arteries. Changes in carotid artery diameter were determined using the cold pressor test (CPT), which results in production of nitric oxide via sympathetic activation and is one of the novel methods available for assessing endothelial function in the carotid artery. To investigate the effect of resistance training on endothelial function, we designed a cross-sectional study of carotid arterial vasoreactivity to CPT in men participating in regular resistance training with increased carotid arterial stiffness compared with age-matched control subjects. Twelve resistance-trained middle-aged men (age 38.7 +/- 1.7 years) and 17 age-matched control subjects (age 36.8 +/- 1.2 years) were studied. The direction and magnitude of changes in carotid artery diameter were measured by B-mode ultrasonography during sympathetic stress induced by submersion of the foot in ice slush for 90 s. Carotid arterial beta-stiffness index, and systolic and mean arterial blood pressure were higher (7.7 +/- 0.7 versus 6.0 +/- 0.4 arbitrary units, 116 +/- 2 versus 131 +/- 4 mmHg and 86 +/- 2 versus 95 +/- 2 mmHg, respectively, all P &lt; 0.05) in the resistance training group compared with control subjects. There were, however, no significant differences in the amount or percentage change in carotid artery diameter in CPT between the two groups (resistance training group, 0.33 +/- 0.07 mm and 5.2 +/- 1.1%; control group, 0.37 +/- 0.06 mm and 5.8 +/- 0.9%, respectively). These findings suggest that while carotid arterial stiffening and higher blood pressure are observed in regular resistance-trained men, these are not associated with abnormalities in carotid arterial vasoreactivity to sympathetic stimulus, which implies intact endothelial function.

Objective: It has been suggested that exercise has preferential effects on visceral fat reduction. However, the dose-response effect remains unclear because of limited evidence from individual studies. The purpose of this study was to systematically review the current literature to establish whether reduction of visceral fat by aerobic exercise has a dose-response relationship.
Methods: A database search was performed (PubMed, 1966-2006) with appropriate keywords to identify studies exploring the effects of aerobic exercise as a weight loss intervention on visceral fat reduction. Visceral fat reduction was expressed as the percentage of visceral fat change per week (% Delta VF/w). The energy expenditure by aerobic exercise was expressed as Sigma(metabolic equivalents x h per week (METs center dot h/w)).
Results: Nine randomized control trials and seven non-randomized control trials were selected. In most of the studies, the subjects performed aerobic exercise generating 10 METs center dot h/w or more. Among all the selected groups (582 subjects), visceral fat decreased significantly (P &lt; 0.05) in 17 groups during the intervention, but not in the other 4 groups. There was no significant relationship between METs center dot h/w from aerobic exercise and %Delta VF/w in all the selected groups. However, when subjects with metabolic-related disorders were not included (425 subjects), METs center dot h/w from aerobic exercise had a significant relationship with %Delta VF/w (r= -0.75). Moreover, visceral fat reduction was significantly related to weight reduction during aerobic exercise intervention, although a significant visceral fat reduction may occur without significant weight loss.
Conclusion: These results suggest that at least 10 METs center dot h/w in aerobic exercise, such as brisk walking, light jogging or stationary ergometer usage, is required for visceral fat reduction, and that there is a dose-response relationship between aerobic exercise and visceral fat reduction in obese subjects without metabolic-related disorders.

It has been demonstrated in a previous study that resting energy expenditure (REE) is associated with adiponectin levels in the blood. However, body composition was not taken into consideration in that study. The purpose of the present study was to again investigate the relationship between blood adipocytokines and REE, adjusted by body composition, in both young and elderly women. REE and blood adipocytokines were measured in 115 young (age: 22.3 +/- 2.1 y, BMI: 21.3 +/- 1.9 kg/ml) and 71 elderly (63.4 +/- 6.5 y, 22.9 +/- 2.3 kg/m(2)) women. Dual energy X-ray absorptiometry was used to measure percent body fat. Fat mass and fat free mass (FFM) were calculated. REE (kcal/d and kcal/kg BW/d) was lower in elderly women than in young women, but no significant difference was observed in REE, expressed as kcal/kg FFM/d, between the two groups. Although elderly women had a higher percent body fat and higher serum leptin concentrations than young women, plasma adiponectin concentrations did not differ between young and elderly women. In elderly women, REE (kcal/d) was significantly and inversely correlated with plasma adiponectin concentration (r = -0.386, p&lt;0.001), but REE expressed per kilogram of BW or FFM was not significantly correlated. Furthermore, no significant correlation was observed between REE (kcal/d) and concentrations of plasma adiponectin or serum leptin, after adjusting for potential confounders such as body composition and hormones, in either age group. These results suggest that adipocytokines do not influence REE in adult women.

We evaluated the linkage between oxygen uptake at the ventilatory threshold (VT) and muscle strength in subjects with and without metabolic syndrome. We used data of 226 Japanese men with metabolic syndrome and 265 Japanese men without the syndrome. Metabolic syndrome has recently been defined by a new criterion in Japan. Oxygen uptake at VT and muscle strength, i.e. grip strength and leg strength were measured. Oxygen uptake at VT and muscle strength/body weight were found to be significantly lower in subjects with metabolic syndrome than in those without the syndrome. However, the differences did not reach significant levels after adjusting for leg strength/body weight or oxygen uptake at VT. A combination of aerobic exercise and resistance training might be considered for preventing and improving metabolic syndrome.

Objective: We compared the levels of ventilatory threshold (VT) and exercise habits in subjects with metabolic syndrome with those in age, sex-matched subjects without metabolic syndrome.
Methods: We used data of 155 Japanese men (47.1 +/- 9.2 years) with metabolic syndrome; the diagnosis was given by the definition and the diagnostic standard for metabolic syndrome in Japan. The influence of metabolic syndrome on oxygen uptake, work rate and heart rate at VT, and exercise habits were evaluated.
Results: Oxygen uptake and work rate at VT in subjects with metabolic syndrome were significantly lower than those in subjects without metabolic syndrome even after adjusting for body mass index (BMI). The number of subjects with exercise habits was significantly lower in metabolic syndrome. The subjects with exercise habits were significantly older than that in subjects without exercise habits. Furthermore, oxygen uptake and work rate at VT were significantly higher in subjects with exercise habits than those in subjects without exercise habits.
Conclusion: Lower level of VT was characteristic in subjects with metabolic syndrome. Promotion of exercise habits is necessary for preventing and improving metabolic syndrome in Japanese men. (C) 2006 Elsevier Ireland Ltd. All rights reserved.

We compared muscle strength between Japanese men with and without metabolic syndrome. We used data for 323 Japanese men with metabolic syndrome and 893 Japanese men without the syndrome. Metabolic syndrome was defined by a new criterion in Japan, and the parameters for muscle strength, i.e. grip strength, leg strength were measured. Leg strength was found to be significantly higher in subjects with metabolic syndrome than in those without, while muscle strength per body weight was significantly lower in subjects with the syndrome. Lower muscle strength per body weight may be one of the characteristic features in subjects with metabolic syndrome.

Ventilatory threshold (VT) is an important predictor of cardiorespiratory fitness, such as peak oxygen uptake (&lt;(V)over dot &gt;(O2peak)) and is a valuable index of aerobic exercise intensity. However, little is known about the role of skeletal muscle ( SM) mass in the ageassociated decline of VT. Therefore, the present study was performed to investigate the effects of age on cardiopulmonary fitness normalised for regional SM mass in 1,463 Japanese men and women, and to determine the relevance of VT normalised to SM mass based on age and gender. Total, trunk and thigh SM mass were measured using an ultrasound method, while &lt;(V)over dot &gt;(O2pea)k and VT were determined during treadmill walking. &lt;(V)over dot &gt;(O2peak) was estimated using the predicted maximum heart rate ( HR) and the HR-&lt;(V)over dot &gt;(O2) relationship for sub- maximal treadmill walking. There were significant negative correlations between VT normalised for body mass and age in men and women ( P &lt; 0.001). Age- associated declines were also observed in VT normalised for body mass in both men and women; however, VT normalised for SM mass was not significantly different with age. Significant correlations were also observed between thigh SM mass and VT in both men and women. These results suggest that thigh SM mass is closely associated with &lt;(V)over dot &gt;(O2peak) and/ or VT in both men and women, and the decrease in VT with age is predominantly due to an age- related decline of SM mass. Moreover, this study provides normative cardiorespiratory fitness data regarding VT normalised SM mass in healthy men and women aged 20 - 80 years.

It has frequently been demonstrated that prior high-intensity exercise facilitates pulmonary oxygen uptake (VO2) response at the onset of subsequent identical exercise. To clarify the roles of central O-2 delivery and/or peripheral O2 extraction in determining this phenomenon, we investigated the relative contributions of cardiac output (CO) and arteriovenous O-2 content difference (a-(v) over bar DO2) to the VO2 transient during repeated bouts of high-intensity knee extension (KE) exercise. Nine healthy subjects volunteered to participate in this study. The protocol consisted of two consecutive 6-min KE exercise bouts in a supine position (work rate 70-75% of peak power) separated by 6 min of rest. Throughout the protocol, continuous-wave Doppler ultrasound was used to measure beat-by-beat CO (i.e., via simultaneous measurement of stroke volume and the diameter of the arterial aorta). The phase II VO2 response was significantly faster and the slow component (phase III) was significantly attenuated during the second KE bout compared to the first. This was a result of increased CO during the first 30 s of exercise: CO contributing to 100 and 56% of the VO2 speeding at 10 and 30 s, respectively. After this, the contribution of (a-(v) over bar DO2) became increasingly more predominant: being responsible to an estimated 64% of the VO2 speeding at 90 s, which rose to 100% by 180 s. This suggests that, while both CO and a-(v) over bar DO2 clearly interact to determine the VO2 response, the speeding of VO2 kinetics by prior high-intensity KE exercise is predominantly attributable to increases in a-(v) over bar DO2.

Objectives: We investigated the correlation between changes in body weight and body composition parameters. Methods: We used the data of 2635 Japanese (40.2±12.2 years) at baseline and at 1-year follow-up from a database of 13522 subjects, which is available at the Okayama Southern Institute of Health in Okayama prefecture, Japan. Body weight, waist circumference at the umbilical level, hip circumference, and body fat percentage were used in the analyses. Results: Body composition parameters were significantly reduced after 1 year. Changes in body weight significantly correlated with changes in waist circumference, changes in hip circumference, and changes in body fat percentage. A decrease in body weight of 3 kg corresponded to a 3.45 cm decrease in waist circumference in men and a 2.83 cm decrease in that in women. Conclusion: A decrease in body weight of 3 kg corresponded to an almost 3 cm decrease in waist circumference at the umbilical level in Japanese men and women.

The purpose of the present study was to examine the effect of unilateral lower limb suspension (ULLS) deconditioning on oxygen uptake kinetics. Eight healthy males underwent ULLS for 20 days and performed a series of 6-min square-wave transitions from rest to 60-W single-leg cycling exercises just before and after ULLS. To characterize the kinetics of the oxygen uptake response, a single exponential model was applied to the data until the end of the fast component omitted the first 15 s of the on-transit using a nonlinear least-squares fitting procedure. The following results were found: (i) the time constant of oxygen uptake was unchanged before and after ULLS; (ii) although there was no significant difference in the baseline and the asymptotic amplitude of the fast component, the asymptote, i.e., the absolute asymptotic amplitude of the fast component (the sum of the baseline and the asymptotic amplitude), and the end exercise oxygen uptake were decreased after ULLS; (iii) the contribution of the slow component to the total response of oxygen uptake was unchanged at pre- and post-ULLS. In conclusion, the asymptote in the fast component and the end exercise oxygen uptake were decreased after 20-d ULLS, though the response speed and the amplitude of the slow component of oxygen uptake were not changed. It is suggested that deconditioning as a result of limb disuse affects oxygen uptake response.

Objectives This study aimed to determine the effects of moderate resistance training as well as the combined resistance and aerobic training intervention on carotid arterial compliance.
Background Resistance training has become a popular mode of exercise, but intense weight training is shown to stiffen carotid arteries.
Methods Thirty-nine young healthy men were assigned either to the moderate-intensity resistance training (MODE), the combined resistance training and endurance training (COMBO) or the sedentary control (CONTROL) groups. Participants in the training groups underwent three training sessions per week for 4 months followed by four additional months of detraining.
Results All training groups increased maximal strength in all the muscle groups tested (P &lt; 0.05). Carotid arterial compliance (via simultaneous carotid ultrasound and applanation tonometry) decreased approximately 20% after MODE training (from 0.20 +/- 0.01 to 0.16 +/- 0.01 mm(2)/mmHg, P &lt; 0.01). No significant changes in carotid arterial compliance were observed in the COMBO (0.20 +/- 0.01 to 0.23 +/- 0.01 mm(2)/mmHg) and CONTROL (0.20 +/- 0.01 to 0.20 +/- 0.01 mm(2)/mmHg) groups. Following the detraining period, carotid arterial compliance returned to the baseline level. Peripheral (femoral) artery compliance did not change in any groups.
Conclusions We concluded that simultaneously performed aerobic exercise training could prevent the stiffening of carotid arteries caused by resistance training in young healthy men.

健常者12名(男6名・女6名,平均44.2歳)を対象に,仰臥位安静時の膝下丈弾性ストッキング着用による下腿静脈容量をストレンゲージプレチスモグラフにより測定し,駆血用カフ圧-下腿静脈容量曲線より下腿静脈コンプライアンス(VC)を算出した.弾性ストッキングは低圧迫非段階的(LS),中圧迫段階的(MS),高圧迫段階的(HS)のものを使用した.VCは段階的弾性ストッキングの着圧増加に従って上昇傾向を示し,VCの傾きはHS,MSが裸足と比較して有意に上昇した.静脈容量および最大静脈還流量も着圧が増加するに従って増大し,HS,MSは裸足と有意差を認めた.VCと静脈容量および最大静脈還流量は正の相関を示した.段階的弾性ストッキング着用による下腿圧増加は,VCを上昇させ,静脈還流を亢進させることが示唆された

The effect of menstrual cycle phase on arterial elasticity is controversial. In 10 healthy women (20.6 +/- 1.5 years old, mean +/- S.D.), we investigated the variations in central and peripheral arterial elasticity, blood pressure (carotid and brachial), carotid intima-media thickness (IMT), and serum oestradiol and progesterone concentrations at five points in the menstrual cycle (menstrual, M; follicular, F; ovulatory, O; early luteal, EL; and late luteal, LL). Carotid arterial compliance (simultaneous ultrasound and applanation tonometry) varied cyclically, with significant increases from the values seen in M (0.164 +/- 0.036 mm(2) mmHg(-1)) and F (0.171 +/- 0.029 mm(2) mmHg(-1)) to that seen in the O phase (0.184 +/- 0.029 mm(2) mmHg(-1)). Sharp declines were observed in the EL (0.150 +/- 0.033 mm(2) mmHg(-1)) and LL phases (0.147 +/- 0.026 mm(2) mmHg(-1); F=8.51, P &lt; 0.05). Pulse wave velocity in the leg (i.e. peripheral arterial stiffness) did not exhibit any significant changes. Fluctuations in carotid arterial elasticity correlated with the balance between oestradiol and progesterone concentrations. No significant changes were found in carotid and brachial blood pressures, carotid artery lumen diameter, or IMT throughout the menstrual cycle. These data provide evidence that the elastic properties of central, but not peripheral, arteries fluctuate significantly with the phases of the menstrual cycle.

Aim: Fluctuations in autonomic nervous functions throughout the menstrual cycle and the underlying mechanism concerning them are not well known. This study was designed to test the hypothesis that fluctuations in cardiovagal baroreflex sensitivity (BRS) throughout the menstrual cycles of young women are due to fluctuations in carotid arterial distensibility.
Methods: In eight eumenorrhoeic healthy young women (18-24 years), we determined the variations in the carotid arterial distensibility coefficient (DC; via simultaneous ultrasonography and applanation tonometry), cardiovagal BRS (phase IV of the Valsalva manoeuvre and the sequence method; up- or down-sequence spontaneous BRS), and serum oestradiol and progesterone concentrations at five points in the menstrual cycle (menstrual = M, follicular = F, ovulatory = O, early luteal = EL, and late luteal = LL).
Results: Serum oestradiol and progesterone levels were consistent with the predicted cycle phases. Carotid arterial DC fluctuated cyclically, increasing significantly from the M (52.4 +/- 4.9 x 10(-3) kPa(-1), mean +/- SE) and F (52.7 +/- 4.4) phases to the O (57.6 +/- 4.4) phase and declining sharply in the EL (46.0 +/- 4.0) and LL (45.1 +/- 3.0) phases (F = 6.37, P &lt; 0.05). Contrary to our prediction, however, cardiovagal BRS by the Valsalva manoeuvre (P = 0.73) or sequence method (up-sequence spontaneous BRS; P = 0.84: down-sequence spontaneous BRS; P = 0.67) did not change significantly during the menstrual cycle.
Conclusion: The results suggest that, although carotid arterial distensibility fluctuates with the changes in ovarian hormone levels that occur during the menstrual cycle, the fluctuations in carotid arterial distensibility do not influence cardiovagal BRS.

The purpose of the present study was to clarify effect of increase in calf pressure on calf venous compliance. The calf pressures were increased by wearing elastic compression stockings with different pressures (Calf pressure 0, 12, 17, 21 mmHg). Healthy twelve people (six men and six women, 43.3 ± 15.3 years) volunteered to participate in this study. Changes in calf venous volume during spine rest were measured by mercury plethysmography. We analyzed the calf venous compliance by inflating the venous collecting cuff to 60 mmHg for 7 min, then decreasing cuff pressure at 1 mmHg/sec (over 1 min) to 0 mmHg, using cuff pressure as an estimate of venous pressure. This method produced pressure-volume curves fitting the quadratic regression (Δlimb volume) = β 0 + β 1 · (cuff pressure) + β 2 ·(cuff pressure) 2 , where Δ is change. The higher calf venous compliance and volume were observed in with the higher pressure stocking. These results suggest that higher calf pressure induced by wearing elastic compression stocking increases calf venous compliance and maximum venous outflow.

Reductions in basal leg blood flow have been implicated in the pathogenesis of metabolic syndrome and functional impairment in humans. We tested the hypothesis that reductions in basal whole leg blood flow with age are either absent or attenuated in those who perform regular strength training. A total of 104 normotensive men aged 20-34 yr (young) and 35-65 yr (middle aged), who were either sedentary or resistance trained, were studied. Mean and diastolic blood pressures were higher (P &lt; 0.05-0.001) in the middle-aged compared with the young men, but there were no significant differences between the sedentary and resistance-trained groups. In the sedentary group, basal whole leg blood flow (duplex Doppler ultrasound) and vascular conductance were lower (similar to 30 and similar to 38%, respectively; P &lt; 0.01) in the middle-aged compared with the young men. There were no such age-related differences in the resistance-trained group. In the young men, basal whole leg blood flow and vascular conductance were not different between the two activity groups, but, in the middle-aged men, they were higher (similar to 35 and similar to 36%, respectively; P &lt; 0.01) in the resistance-trained men than in the sedentary men. When blood flow and vascular conductance were expressed relative to the leg muscle mass, the results were essentially the same. We concluded that the age-related reduction in basal whole leg blood flow is absent in resistance-trained men. These results suggest that resistance training may favorably influence leg perfusion in aging humans, independent of its impact on leg muscle mass.

To examine the possible age-related blood pressure (BP) deregulation in response to central hypervolemia, we measured spontaneous baroreflex sensitivity (SBRS), carotid arterial compliance (CC), and R-R interval coefficient of variation (RRICV) during basal and thermoneutral resting head-out-of-water immersion (HOWI) in 7 young (YG = 24.0 ± 0.8 years) and 6 middle-aged/older (OL = 59.3 ± 1.3 years) healthy men. Compared with basal conditions (YG = 19.6 ± 4.0 vs OL = 6.1 ± 1.5 ms/mmHg, P &lt
0.05), SBRS remained higher in YG than OL during rest HOWI (YG = 23.6 ± 6.6 vs OL = 9.3 ± 2.1 ms /mmHg, P &lt
0.05). The RRICV was significantly different between groups (YG = 6.5 ± 1.4 vs OL = 2.8 ± 0.4%, P &lt
0.05) under HOWI. The OL group had no increase in CC, but a significant increase in systolic BP (basal = 115.3 ± 4.4 vs water = 129.3 ± 5.3 mmHg, P &lt
0.05) under HOWI. In contrast, the YG group had a significant increase in CC (basal = 0.16 ± 0.01 vs water = 0.17 ± 0.02 mm2/mmHg, P &lt
0.05) with no changes in systolic BP. SBRS was positively related to CC (r = 0.58, P &lt
0.05 for basal vs r = 0.62, P &lt
0.05 for water). Our data suggest that age-related vagal dysfunction and reduced CC may be associated with SBRS differences between YG and OL groups, and with BP elevation during HOWI in healthy older men.

Background - Reductions in the compliance of central arteries exert a number of adverse effects on cardiovascular function and disease risk. Endurance training is efficacious in increasing arterial compliance in healthy adults. We determined the effects of resistance training on carotid arterial compliance using the intervention study design.
Methods and Results - Twenty-eight healthy men 20 to 38 years old were randomly assigned to the intervention group ( n = 14) and the control group ( n = 14). Control subjects were instructed not to alter their normal activity levels throughout the study period. Intervention subjects underwent 3 supervised resistance training sessions per week for 4 months and detraining for a subsequent 4 months. The resistance training increased maximal strength in all muscle groups tested ( P &lt; 0.001). There were no significant differences in baseline arterial compliance and &beta;-stiffness index between the intervention and control groups. In the intervention group, carotid arterial compliance decreased 19% ( P &lt; 0.05), and beta-stiffness index increased 21% ( P &lt; 0.01) after resistance training. These values returned completely to the baseline levels during the detraining period. Arterial compliance did not change in the control group. In both groups, there were no significant changes in brachial and carotid blood pressure, carotid intima-media thickness, lumen diameter, and femoral arterial compliance. Changes in carotid artery compliance were significantly and negatively related to corresponding changes in left ventricular mass index ( r = - 0.56, P &lt; 0.001) and left ventricular hypertrophy index ( r = - 0.68, P &lt; 0.001).
Conclusions - In marked contrast to the beneficial effect of regular aerobic exercise, several months of resistance training "reduces" central arterial compliance in healthy men.

It has frequently been demonstrated that prior heavy cycling exercise facilitates pulmonary VO2 kinetics at the onset of subsequent heavy exercise. This might be due to improved muscle perfusion via acidosis-induced vasodilating effects. However, it is difficult to measure the blood flow (BF) to the working muscles (via the femoral artery) during cycling exercise. We therefore selected supine knee extension (KE) exercise as an alternative, and investigated whether the faster VO2 kinetics in the 2nd bout was matched by proportionally faster BF kinetics to the exercising muscle. Nine healthy subjects (aged 21-44 years) volunteered to participate in this study. The protocol consisted of two consecutive 6-min KE exercise bouts in a supine position (work rate: 70-75% of peak power) separated by a 6-min baseline rest (EX1 to EX2). During the protocol, a pulsed Doppler ultrasound technique was utilized to continuously measure the BF in the right femoral artery. The protocol was repeated at least 6 times to characterize the precise kinetics. In agreement with previous studies using cycling exercise, the VO2 kinetics in the 2nd bout were facilitated compared with that in the 1st bout [mean +/- S.D. of the 'effective' time constant (tau): EXI, 68.6 +/- 15.9, versus EX2, 58.0 +/- 14.4 s. Phase II-tau: EX1, 48.7 +/- 9.0, versus EX2, 41.2 +/- 13.3 s. Empirical index of the slow component (DeltaVO(2(6-3))): EX1, 78 +/- 44, versus EX2, 57 +/- 36 ml min(-1) (P &lt; 0.05)]. However, no substantial difference was observed for the facilitation of the femoral artery BE response to the 1st and 2nd exercise bouts [i.e. the (effective' &tau; of the femoral artery BF: EX1, 40.8 &PLUSMN; 16.9, versus EX2, 39.0 &PLUSMN; 17.1 s (P &gt; 0.05)]. It was concluded that the faster pulmonary VO2 kinetics during heavy KE exercise following prior heavy exercise was not associated with a similar modulation in the BF to the working muscles.

Aims: The Modelflow method can estimate cardiac Output from arterial blood pressure waveforms using a three-element model of aortic input impedance (aortic characteristic impedance, arterial compliance, and systemic vascular resistance). We tested the reliability of a non-invasive cardiac output estimation during submaximal exercise using the Modelflow method from finger arterial pressure waveforms collected by Portapres in healthy young humans.
Methods: The Doppler echocardiography method was used as a reference method. Sixteen healthy young subjects (nine males and seven females) performed a multi-stage cycle ergometer exercise at an intensity corresponding to 70, 90, 110 and 130% of their individual ventilatory threshold for 2 min each. The simultaneous estimation of cardiac output (15 s averaged data) using the Modelflow and Doppler echocardiography methods was performed at rest and during exercise.
Results and Conclusion: The Modelflow-estimated cardiac output correlated significantly with the simultaneous estimates by the Doppler method in all subjects (r = 0.87, P &lt; 0.0001) and the SE of estimation was 1.93 L min(-1). Correlation coefficients in each subject ranged from 0.91 to 0.98. Although the Modelflow method overestimated cardiac output, the errors between two estimates were not significantly different among the exercise levels. These results suggest that the Modelflow method using Portapres could provide a reliable estimation of the relative change in cardiac output non-invasively and continuously during submaximal exercise in healthy young humans, at least in terms of the relative changes in cardiac output.

Reductions in the compliance of central arteries exert a number of adverse effects on systemic cardiovascular function and disease risk. Using the cross-sectional study design, we determined the relation between chronic resistance training and carotid arterial compliance. A total of 62 healthy normotensive men, 20 to 39 years of age (young) and 40 to 60 years of age (middle-aged), who were either sedentary or resistance-trained, were studied. In both activity groups, carotid arterial compliance (simultaneous ultrasound and applanation tonometry) was lower (P&lt;0.05) in the middle-aged compared with the young men. There was no significant difference between young sedentary and resistance-trained men. In the middle-aged group, carotid arterial compliance in the resistance-trained men was &AP;30% lower (P&lt;0.01) than their sedentary peers. Femoral artery compliance and arm pulse wave velocity (measures of peripheral artery stiffness) were not different among any groups. Left ventricular hypertrophy index (echocardiography) was greater (P&lt;0.05) in resistance-trained compared with sedentary men and was associated with carotid arterial compliance (r= -0.35; P&lt;0.01). We concluded that (1) resistance training is associated with the smaller central arterial compliance in healthy middle-aged men; (2) age-related reductions in arterial compliance was greater in resistance-trained men than in sedentary men; and (3) the lower arterial compliance in the resistance-trained men is associated with left ventricular hypertrophy. In marked contrast to the beneficial effect of regular aerobic exercise, the present findings are not consistent with the idea that resistance training exerts beneficial influences on arterial wall buffering functions.

Endurance-trained athletes with higher aerobic power (Vo_2max) have a large-sized left ventricle (LV) and aorta (Ao). We therefore hypothesized that the individual variability of Vo_2ax can be estimated using resting LV and Ao dimensions. In looking at this question we performed a laboratory-based cross-sectional study to determine the relationship between Vo_2max, LV dimensions, and Ao dimensions in young subjects with wide ranges of physical activity status. One hundred forty-two healthy young men (20-35 years), who were either sedentary, recreationally active or endurance-trained, participated in the cross-sectional study. Subsequently, a meta-analysis approach was used to collect 28 studies involving 58 groups and 816 subjects. LV and Ao dimensions were determined by echocardiography at supine rest. In the cross-sectional study and meta-analysis, LV end-diastolic diameter (LVEDD) and end-systolic diameter (LVESD), posterior wall thickness (PWT) and inter-ventricular septum thickness (IVST), and Ao diameter (AoD) were positively and significantly correlated with Vo,max. When we performed a stepwise regression analysis in the cross-sectional study to determine independent predictors of Vo_2max, the variables entered were LVEDD, AoD, and PWT, which together explained 60-70% of the variability. Furthermore, we attempted to develop equations for predicting Vo_2max. Multiple regression analyses using LVEDD, AoD, and PWT as the explanatory variables for predicting Vo2max yielded the following equations. Vo_2max (ml・min^&lt;-1&gt;・kg^&lt;-1&gt;) = 49.2 LVEDD (mm/kg) + 27.2 AoD (mm/kg) + 43.9 IVST (mm/kg) -2.6. These results suggest that the variability of Vo_2max can be accounted for by differences in both left ventricular and aortic structure. Furthermore, echocardiography at supine-rest was useful for evaluating maximal aerobic power, specifically for young healthy men, who demonstrated a wide range of trained states.

The aim of this study was to clarify the effects of water immersion on the cardiovascular recovery process following submaximal steady state exercise on land. Seven male subjects (23 yrs old) underwent experiments under four separate conditions on separate days (15 minutes of cycling exercise at 50% and 80% maximal oxygen consumption followed by 16 minutes of recovery in a sitting position in water and out of water). Concerning conditions in water, mean water temperature was 29.4 degrees, and the immersion level was set at xiphoid. Mean room temperature in out of water conditions, and during all conditions of exercise was 24.4 degrees. Oxygen consumption (V̇O2), heart rate (HR) and blood pressure (systolic: SBP, diastolic: DBP) were measured under each condition. Mean blood pressure was calculated from SBP and DBP (MBP=1/3 X (SBP-DBP) + DBP). Stroke volume (SV) was measured by Doppler echocardiography, and then cardiac output (CO=SV X HR), total peripheral resistance (TPR=MBP/CO) and arterial-mixed venous oxygen difference (a-v̄ O2diff=V̇O2/CO) were calculated. In comparison with the same exercise intensity condition, there were no Significant differences between recovery processes of V̇O2, HR, SBP, DBP and MBP in and out of water. SV and CO were significantly higher (p&lt
0.05) during the recovery process in water than out of water (SV: at 50 and 80% maximal oxygen consumption conditions, CO: at 80% condition). The TPR and a-v̄ O2diff were significantly lower (p&lt
0.05) during the recovery process in water than out of water at 80% oxygen consumption condition. These results indicate that water immersion facilitates circulating blood volume during the recovery process without increasing blood pressure, especially during recovery after high intensity exercise. Therefore, we suggest that increased left ventricular preload with immersion would be an important factor in cardiovascular regulation not only at rest but also during recovery after exercise.

Appendicular skeletal muscle mass decreases with advancing age, and this is thought to be a key factor for reductions in functional independence in the elderly. We determined the potential modulatory influence of regular aerobic exercise on the age-related reductions in appendicular muscle mass. In the present cross-sectional study, we studied a total of 131 healthy men aged 20-79 years. For at least the previous 2 years subjects were either sedentary or endurance-trained. Appendicular skeletal muscle mass was measured using dual-energy X-ray absorptiometry. There were no significant group differences in height. Body mass and body surface area were lower in endurance-trained compared with sedentary men (P&lt;0.05). In general, body fat increased with age in both groups, but was lower in endurance-trained compared with sedentary men at any age group (P&lt;0.05). Lean body mass and maximal oxygen consumption decreased with age (P&lt;0.05). Irrespective of expression (absolute, relative to body surface area, or relative to body mass), arm, leg, and total limb muscle mass generally decreased with age. Absolute appendicular muscle mass was not different between the two activity groups. When expressed relative to body mass or body surface area, appendicular muscle mass in the endurance-trained middle-aged and older men was significantly higher than their sedentary peers. The rate of decline in appendicular muscle mass with age was similar between the two activity groups. The results of the present cross-sectional study indicate that endurance-trained men had significantly higher appendicular skeletal muscle mass relative to body mass or body size compared with their sedentary peers. This may contribute, at least in part, to the lower incidence of functional disability observed in middle-aged and older men who exercise regularly.

We investigated whether the autonomic nervous system (ANS) modulation contribute to the bradycardia induced by endurance training. First, the meta-analysis approach was used to collect group mean values of maximal oxygen consumption (Vo(2)max) and heart rate variability (HRV) from 14 studies involving 30 groups and 485 subjects. Subsequently, we performed a cross-sectional (n=116) and intervention (n=training group : 10 and control group : 6) studies. In both studies, ANS modulation was estimated by spectral analysis of HRV. In the meta-analysis and cross-sectional study, HR and natural logarithmic high frequency power (In HF power) were correlated with Vo(2)max or peak oxygen uptake (peak Vo(2)). The significant negative correlations were found between HR and In HF power ( meta-analysis and the cross-sectional study; r(2) = 0.42 and 0.44, respectively). Endurance training in the intervention study increased peak Vo(2) and resting In HF power, and decreased resting HR. These results strongly suggest that endurance training induces an increase in resting ANS modulation especially parasympathetic modulation. Furthermore, about half of the variability of resting HR can be accounted for by difference in parasympathetic modulation.

The cross-sectional area (CSA) of large-conductance arteries increases in response to endurance training in humans. To determine whether training-induced changes in arterial structure are systemic in nature or, rather, are confined to the arteries supplying exercising muscles, we studied 10 young men who performed one-legged cycle training [80% of one-legged peak O-2 uptake ((V) over dot O-2peak), 40 min/day, 4 days/wk] for 6 wk and detraining for another 6 wk. There were no significant differences in baseline one-legged (V) over dot O-2peak and CSA of the common femoral artery and vein (via B-mode ultrasound) between experimental and control legs. In the experimental leg, one-legged (V) over dot O-2peak increased 16% [from 3.0 +/- 0.1 to 3.4 +/- 0.1 (SE) l/min], arterial CSA increased 16% (from 84 +/- 3 to 976+/- 5 mm(2)), and venous CSA increased 46% (from 56 +/- 5 to 82 +/- 5 mm(2)) after endurance training. These changes returned to baseline during detraining. There were no changes in one-legged (V) over dot O-2peak and arterial CSA in the control leg, whereas femoral venous CSA in the control leg significantly increased 24% (from 54 +/- 5 to 67 +/- 4 mm(2)) during training. Changes in femoral arterial and venous CSA in the experimental leg were positively and significantly related to corresponding changes in one-legged (V) over dot O-2peak (r = 0.86 and 0.76, respectively), whereas there were no such relations in the control leg (r = 0.10 and 0.17). When stepwise regression analysis was performed, a primary determinant of change in (V) over dot O-2peak was change in femoral arterial CSA, explaining similar to 70% of the variability. These results support the hypothesis that the regional increase in blood flow, rather than systemic factors, is associated with the training-induced arterial expansion. Femoral arterial expansion may contribute, at least in part, to improvement in efficiency of blood transport from the heart to exercising muscles and may facilitate achievement of aerobic work capacity.

During water immersion bradycardia and increase in stroke volume induce by changing in hydrostatic pressure. We hypothesised that the cardiac alterations with immersion are associates with an increase in venous return from lower body. Because the venous return reflects volume of capacitance vein e.g, inferior vena cava. Therefore, we clarified the effects of water immersion on the size in left ventricle, aorta, and vena cava.

Purpose: Endurance training induces reductions in both resting and postexercise heart rate (HR). If adaptation in cardiac autonomic regulation is a contributing factor in these reductions, changes in cardiac autonomic nervous system (ANS) should correspond to those in HR during an endurance-training program. We investigated the changes in resting and postexercise HR variabilities (both in the time and frequency domain) over a 6-wk training program. Methods: HR variability was measured five times in an endurance-training group (N = 7) and four times in a control group (N = 5) during the course of study. Results: Endurance training decreased HR and increased indices of parasympathetic modulation measured both at rest and during postexercise recovery periods. Noteworthy is that no changes in either HR or indices of ANS modulation measured during postexercise recovery periods were detectable after the first 7 d of the study despite continued changes in resting HR and indices in ANS modulation measured between the 7th and 42nd days of the endurance-training program. Conclusions: The study demonstrates that with endurance-training changes in cardiac ANS modulation partly contribute to a decrease in HR at rest and during postexercise recovery period, and that adaptation of the cardiac autonomic control occurs sooner in immediate postexercise periods than at rest.

In a recent study, endurance athletes, i.e. cyclists and long-distance runners, were found to have larger arterial conductance vessels than untrained controls. The aim of the present study was to determine the blood flow profiles of dilated vessels in these endurance-trained athletes. Twelve endurance-trained athletes(ET group) and twelve untrained control subjects (UC group) volunteered for the study. The cross-sectional area (CSA), peak and mean blood velocity in the ascending aorta (pV and mV), blood pressure (BP), and heart rate (HR) were measured in the semi-supine position on a cycle ergometer fitted with a backrest, at rest and during exercise at 40%, 60%, and 80% (V) over dot O-2 max. Furthermore, stroke volume (SV), cardiac output (CO), total peripheral resistance, and double product were calculated. The SV and CO of the ET group were significantly larger than those of the UC group during exercise. The CSA of the ascending aorta in the ET group was significantly larger than that in the UC group at rest and during exercise. There were no differences in the mV and mean BP between the two groups. Upon comparison at the same SV, pV, mV, the total peripheral resistance, and double product of the ET group were lower than those of the UC group. These results suggest that the dilation of the arterial conductance vessels with endurance training contributes to an increase in blood flow to the exercising muscles without a rise in mechanical stress (shear stress and pressure) to the aortic wall. In other words, the arterial conductance vessels adapt morphologically to maintain an adequate degree of the mechanical stress on the aortic wall.

The muscle fiber-capillary barrier consists of the capillary endothelium and the interstitium. Thinning of the barrier is physiologically significant for gas exchange in skeletal muscle because it shortens the diffusion distance of gases. The purpose of the present study was to examine the effect of endurance training on the ultrastructure of the muscle fiber-capillary barrier in soleus muscle of growing rats. Seventeen male Fischer 344 rats, aged 5 weeks, were assigned to either an exercise-trained group (ET, n=5), a paired-weight sedentary group (PWS, n=6), or a sedentary group (S, n = 6), and matched as closely as possible with regard to body mass and (V) over dot o(2max). The ET group performed a treadmill running program for 5 days/week for 10 weeks. The ET and S rats were freely fed rat chow and water. The PWS rats had their food intake restricted so that their mean body mass would be the same as that of the ET rats. After the training period, the diffusion distance in the ET group was significantly shorter than that in the PWS and S groups. There were no differences in the thicknesses of the capillary endothelium among the three groups, but the interstitium was significantly thinner in the ET group than in the PWS and S groups. The degree of decrease in the interstitium thicknesses in the ET group was almost equal to that of the diffusion distance. Therefore it was identified that endurance training shortens the diffusion distance, which depends on thinning of the interstitium. These results suggest that morphological adaptation to endurance training partly contributes to the improvement of gas exchange in the muscle and aerobic work capacity.

A study was conducted to determine non-invasively the effects of endurance training on the size of the inferior vena cava in humans. Twelve healthy male subjects were assigned to either an exercise-trained group (ET, n=7) or a sedentary control group (S, n=5). The ET group underwent cycle-endurance training for 8 weeks (80%(V) over dot o(2)max, 40 min/day, 4 days/week), The S group led normal lives during the 8-week period. Before and after the training period, cross-sectional areas (CSA) of the inferior vena cava and the ascending and abdominal aorta were measured by echography. The CSA of the inferior vena cava after training was significantly larger than that before training in the ET group. There was no significant difference in the S group. These results indicate that the inferior vena cava can be morphologically altered as an adaptive response to endurance training. We consider that this adaptation partly contributes to the improvement in the efficiency of venous return from exercising muscles to the heart. Although the present training also increased the CSA of the aorta, the degree of change was smaller than that seen in the inferior vena cava, implying that the factors of adaptation and adaptability to endurance training in the inferior vena cava differ from those in the aorta.

The purpose of the present study was to clarify longitudinally the effects of exercise training on arterial O2 saturation (Sa(O)2) and ventilation during heavy exercise. A group of six subjects (training group) volunteered to train four times a week for 12 weeks. Each training session consisted of five 3-min periods of exercise on a cycle ergometer at a power output of 100% maximal O2 uptake (V̇O(2 max)), interspersed with 2 min recovery period cycling at 50% V̇O(2 max). During the training, V̇O(2 max), Sa(O)2, the ventilatory equivalent for oxygen (V̇E/V̇O2), and the end- tidal partial pressure of O2 (PET(O)2) during heavy exercise were measured periodically. The same parameters were measured simultaneously in another group of five subjects (control group) who led normal lives. Maximal interval training increases V̇O(2 max), with little change in V̇E(max) and pulmonary functions at rest. The training decreased PET(O)2, V̇E/V̇O2, and Sa(O)2 during heavy exercise. Sa(O)2 is significantly related to V̇E/V̇O2 (r2 = 0.49). These results suggest that less hyperventilatory response to exercise occurs with progress in physical training because the adaptability of ventilatory capacity is less than that of aerobic work capacity, which half induces arterial O2 desaturation during heavy exercise. PET(O)2 as well as V̇E/V̇O2 and V̇O(2 max) did not change anymore after the 6th week, nevertheless Sa(O)2 kept decreasing up to the last 2 weeks. In addition, when the Sa(O)2-V̇E/V̇O2 plot was compared between the two groups, the regression line of the training group was steeper than that of the control groups
i.e., compared at a lower level of V̇E/V̇O2 (~30 ml · ml-1), the Sa(O)2 of the trained subjects exercising at a higher V̇O2 level was lower than that of the control subjects. Predominance of less hyperventilation and another factor, increased A-aDO2, in the genesis of arterial hypoxemia and O2 desaturation may be dependent upon V̇O2 levels in heavy exercise and the state of training.

健康成人女性6名(平均年齢;56歳)について,水中リラクゼーション(水中条件),陸上でのリラクゼーション(陸上条件)は,仰臥位をとり各条件とも15分間のリラクゼーションを行った.室温は32℃,水温は31℃とした.水中条件における開始5分後の収縮期血圧(133.7±14.3mmHg)は,陸上条件の収縮期血圧(121.7±16.0mmHg)と比較し有意に高値(p<0.01)を示した.心拍数及び酸素摂取量は,有意差は認められなかった

The purpose of the present study was to compare between healthy male endurance trained athletes (T, n=6) and sedentary control subjects (S, n = 6) for the blood velocity profile in left ventricle at rest and during exercise. Peak velocity of blood injection into the left ventricle at diastole (dV), peak velocity of blood ejection out of the left ventricle at systole (sV), duration of blood injection (dD) and duration of blood ejection (sD) were measured by pulsed Doppler sonography at rest and during cyclic ergometer exercise at intensity of 40, 60 and 80% maximal O-2 uptake ((V) over dot o(2)max). The dV tended to bt higher T than S at rest and during exercise at all intensities, and statistical significance existed at rest and during exercise at 80%(V) over dot o(2)max. However, there was no significant differences in the sV between T and S. In addition, the dV/sV in T was significantly highter than that in S at rest and during exercise at ail intensities. These results indicate that fulling velocity on the left ventricle in T was faster than that in S. In other words, these indicate that preload on the left ventricle in T was larger than that in S. Moreover, the relationship between stroke volume and dV (r=0.50, p&lt;0.001) was closer than that between stroke volume and sV (r=0.30) in all subjects at rest and during exercise. These data suggest that the contribution of enhanced dV was stronger than that of sV to the larger stroke volume observed in dV.

The aim of the present study was to determine non-invasively the effects of endurance training on both the size and blood flow of the arterial conductance vessels during exercise by men. Twelve healthy male subjects were assigned to either an exercise-trained group (ET, n = 7) or a sedentary control group (S, n = 5). The ET group underwent cycle-endurance training for 8 weeks (80% V̇O2(max), 40 min day-1, 5 days week-1). The S group led normal lives during the 8-week period. Before and after the training period, cross-sectional areas (CSA) of the ascending and abdominal aorta were measured by echography. Measurements were taken in the semisupine position on a cycle ergometer fitted with a backrest, at rest and during 40, 60 and 80% V̇O2(max) of exercise. In addition, Doppler ultrasonographic velocity and flow in the ascending aorta were simultaneously measured. The CSA of the ascending and abdominal aorta after training were significantly larger than those before training in the ET group. Although there were no significant differences in the peak and mean velocities in the ascending aorta before and after the training in the ET group, the blood flow in the ascending aorta during exercise after training was significantly larger than that found before training at each relative intensity. There were no significant differences in any of the Doppler echographic parameters in the S group. These findings suggest that the arterial conductance vessels can be morphologically altered in an adaptive response to the endurance training. Furthermore, the dilation of the conductance vessels with endurance training contributes to an increase in blood flow to the exercising muscles without a rise in blood velocity. In other words, the arterial conductance vessels adapt to maintain adequate blood velocity and shear stress.

To evaluate the magnitude of the stress on the aerobic and the anaerobic energy release systems during high intensity bicycle training, two commonly used protocols (IE1 and IE2) were examined during bicycling. IE1 consisted of one set of 6-7 bouts of 20-s exercise at an intensity of approximately 170% of the subject's maximal oxygen uptake (V over dot(2max)) with a 10-s rest between each bout. IE2 involved one set of 4-5 bouts of 30-s exercise at an intensity of approximately 200% of the subject's V over dot(2max) and a 2-min rest between each bout. The accumulated oxygen deficit of IE1 (69 +/- 8 ml . kg(-1), N = 9), p &lt; 0.01). The accumulated oxygen deficit of IE1 was not significantly different from the maximal accumulated oxygen deficit (the anaerobic capacity) of the subjects (69 +/- 10 ml . kg(-1)), whereas the corresponding value for IE2 was less than the subjects' maximal accumulated oxygen deficit (P &lt; 0.01). The peak oxygen uptake during the last 10 s of the IE1 (55 +/- 6 ml . kg . min(-1)) was not significantly less than the V over dot(2max) of the subjects (57 +/- 6 ml . kg(-1). min(-1)) ws lower than the V over dot(2max) (P &lt; 0.01). In conclusion, this study showed that intermittent exercise defined by the IE1 protocol may tax both the anaerobic and aerobic energy releasing systems almost maximally.

This study consists of two training experiments using a mechanically braked cycle ergometer. First, the effect of 6 wk of moderate-intensity endurance training (intensity: 70% of maximal oxygen uptake (VO2max), 60 min . d(-1), 5 d . wk(-1)) on the anaerobic capacity (the maximal accumulated oxygen deficit) and VO2max was evaluated. After the training, the anaerobic capacity did not increase significantly (P &gt; 0.10), while VO2max increased from 53 +/- 5 ml . kg(-1). min(-1) to 58 +/- 3 ml . kg(-1). min(-1) (P &lt; 0.01) (mean +/- SD). Second, to quantify the effect of high-intensity intermittent training on energy release, seven subjects performed an intermittent training exercise 5 d . wk(-1) for 6 wk. The exhaustive intermittent training consisted of seven to eight sets of 20-s exercise at an intensity of about 170% of VO2max with a 10-s rest between each bout. After the training period, VO2max increased by 7 ml . kg(-1). min(-1), while the anaerobic capacity increased by 28%. In conclusion, this study showed that moderate-intensity aerobic training that improves the maximal aerobic power does not change anaerobic capacity and that adequate high-intensity intermittent training may improve both anaerobic and aerobic energy supplying systems significantly, probably through imposing intensive stimuli on both systems.

The purpose of the present study was to investigate the effect of maximal interval training for 10 weeks on arterial oxygen saturation (SaO2) and ventilatory response during heavy exercise. Seven subjects volunteered for participation in the study. All subjects performed an interval training 4 days per week. Training protocol per day consisted of five periods of exercise of 3-min duration on a cycle ergometer at a power output on 100% maximal oxygen uptake (V̇O2max), interspersed with 2-min recovery cycle at 50%V̇O2max. V̇O2max and ventilatory data measured every week. SaO2, end-tidal oxygen partial pressure (PETO2), end-tidal carbon dioxide partial pressure (PETCO2) and the ventilatory equivalent for oxygen (V̇E/V̇O2) measured during 5-min heavy exercise at 90%V̇O2max every other week. V̇O2max significantly increased from 52.5±4.9 to 60.6±5.8 ml·ml-1·kg-1 during the training. Sao2 reduced significantly from 95.4±1.1 to 93.3±1.8%, similarly PETO2 and V̇E/V̇O2 reduced during the training. A significant positive correlation was found among SaO2, PETO2 and V̇E/V̇O2 during heavy exercise (SaO2-PETO2, r2=0.48, P&lt
0.05
Sao2-V̇E/V̇O2, r2= 0.49, P&lt
0.05
PETO2-V̇E/V̇O2, r2=0.81, P&lt
0.05). These results suggest that ∼50% of the arterial O2 desaturation during heavy exercise can be accounted for by low ventilatory response. Therefore the maximal intervsal training induced arterial O2 desaturation during heavy exercise, which can be half explained by low ventilatory response.

To clarify the mechanism responsible for the increase in stroke volume (SV) due to training, we investigated the effects of interval training on the left ventricle using M-mode echocardiography. Six healthy male subjects volunteered to undergo 48 training sessions for 12 weeks (4 sessions* week −1). One session consisted of five periods of exercise of 3-min duration on a cycle ergometer at a power output of 100% maximal O2 uptake (Vo2max), interspersed with 2-min recovery cycling at 50% Vo2max. The echocardiograms at rest and during mild exercise (100 W) were recorded before and after the training. The interval training significantly increased Vo2max. Although there was no significant difference in SV at rest before and after the training, the training increased SV significantly during exercise. Before the training, there was a significant difference in left ventricular end-diastolic dimension (LVEDD) and left ventricular end-diastolic volume (LVEDV) at rest and during exercise. However, after the training, LVEDD and LVEDV during exercise were significantly larger than those at rest. These results suggest that interval training for 12 weeks increases diastolic filling (elasticity) of the left ventricle during exercise in healthy young men, partly contributing to the increase in SV due to the training. © 1995, The Japanese Society of Physical Fitness and Sports Medicine. All rights reserved.

成人男子5名,成人女子2名を対象に陸上,水中,粘性の高い水中の3条件下でトレッドミル歩行を15分間行わせ,その間の心拍数,酸素摂取量を比較した。1)粘性の高い水中での歩行中の酸素摂取量は他の2条件よりも有意に高い値を示した。陸上歩行と水中歩行との間に有意な差は見られなかった。2)心拍数でも粘性の高い水の中での歩行は他の2条件よりも有意に高い値を示した。陸上歩行と水中歩行との間に有意差は見られなかった。3)水中歩行及び粘性の高い水の中での歩行時にK+濃度の上昇が観察された

Recent evidence suggested that exercise-induced arterial O2 desaturation may occur in highly trained endurance athletes. So, Dempsey brought the hypothesis that the pulmonary capacity for oxygen transport cannot meet superior demands imposed by cardiovascular system in highly trained endurance athletes, and endurance training primarily causes adaptation in the skeletal muscles and in the systemic cardiovascular system, with little change in the pulmonary system. In the present study, we determined the propriety of the hypothesis due to measure the ventilatory capacity of endurance athletes. Sixteen highly trained endurance athletes (ET) and thirteen untrained subjects (UT) volunteered to participate in these experiments. All subjects performed the four experiments, 1) the highest oxygen uptake (peak VO2) during incremental cycle exercise and ventilation (VE), ventilatory equivalent for O2 (VE/VO2) and arterial O2 saturation (SaO2) at which peak VO2 was observed, 2) the maximal voluntary ventilation for 30 sec at rest (MVV), 3) the pulmonary diffusing capacity for CO (DLCO) and expressed per unit of alveolar lung volume (KCO) at rest by the single breath method, and 4) the ventilatory response to hypercapnia (S) at rest by rebreathing method, were measured. The peak VO2 of ET (66.7 ml.min-1.kg-1) was significantly (30.8%) higher than UT (52.4 ml.min-1.kg-1), and VE/VO2 and SaO2 of ET (29.3 and 93.7%, respectively) were significantly lower than UT (34.6 and 95.8%). There were no differences in VE, MVV, DLCO, and S between two groups.

The purpose of the present study was to investigate the contribution of ventilation to arterial O2 desaturation during maximal exercise. Nine untrained subjects and 22 trained long-distance runners [age 18-36 yr, maximal O2 uptake (V̇O(2 max) 48-74 ml · min-1 · kg-1] volunteered to participate in the study. The subjects performed an incremental exhaustive cycle ergometry test at 70 rpm of pedaling frequency, during which arterial O2 saturation (Sa(O2)) and ventilatory data were collected every minute. Sa(O2) was estimated with a pulse oximeter. A significant positive correlation was found between Sa(O2) and end-tidal PO2 (PET(O2)
r = 0.72, r2 = 0.52, P &lt
0.001) during maximal exercise. These statistical results suggest that ~50% of the variability of Sa(O2) can be accounted for by differences in PET(O2), which reflects alveolar PO2. Furthermore, PET(O2) was highly correlated with the ventilatory equivalent for O2 (VE/V̇O2
r = 0.91, P &lt
0.001), which indicates that PET(O2) could be the result of ventilation stimulated by maximal exercise. Finally, Sa(O2) was positively related to V̇E/V̇O2 durimg maximal exercise (r = 0.74, r2 = 0.55, P &lt
0.001). Therefore, one-half of the arterial O2 desaturation occurring during maximal exercise may be explained by less hyperventilation, specifically for our subjects, who demonstrated a wide range of trained states. Furthermore, we found an indirect positive correlation between Sa(O2) and ventilatory response to CO2 at rest (r = 0.45, P &lt
0.05), which was mediated by ventilation during maximal exercise. These data also suggest that ventilation is an important factor for arterial O2 desaturation during maximal exercise.

The effects of low blood glucose concentration during low-intensity prolonged physical exercise on the hypothalamus-pituitary-adrenocortical axis were investigated in healthy young men. In experiment 1, six subjects who had fasted for 14 h performed bicycle exercise at 50% of their maximal O2 uptake until exhaustion. At the end of the exercise, adrenocorticotropic hormone (ACTH) and cortisol increased significantly. However, this hormonal response was totally abolished when the same subjects exercised at the same intensity while blood glucose concentrations were maintained at the preexercise level. In experiment 2, in addition to ACTH and cortisol, the possible changes in plasma concentration of corticotropin-releasing factor (CRF) were investigated during exercise of the same intensity performed by six subjects. As suggested by a previous study (Tabata et al. Clin. Physiol. Oxf. 4: 299- 307, 1984), when the blood glucose concentrations decreased to &lt
3.3 mM, plasma concentrations of CRF, ACTH, and cortisol showed a significant increase. At exhaustion, further increases were observed in plasma CRF, ACTH, and cortisol concentrations. These results demonstrate that decreases in blood glucose concentration trigger the pituitary-adrenocortical axis to enhance secretion of ACTH and cortisol during low-intensity prolonged exercise in humans. The data also might suggest that this activation is due to increased concentration of CRF, which was shown to increase when blood glucose concentration decreased to a critical level of 3.3 mM.

1.食事や運動に伴う代謝の生化学や生理学の基礎的な知識は、効果的な理学療法に有用である。2.日本人の標準的な栄養摂取・身体活動状況については、国民健康・栄養調査や食事摂取基準および身体活動基準などから知ることができる。3.適切な食事・栄養摂取と身体活動の指導には、食事・栄養摂取や身体活動のアセスメント技術の習得が必要である。4.健康食品や食品表示に関する基礎知識は患者とのコミュニケーションに役立つ。(著者抄録)

＜Headline＞1 スポーツ活動により代謝が亢進し、代謝量の算出にメッツ(METs)値を用いることができる。2 有酸素系は酸素摂取量で、CP系と解糖系は酸素借で代謝機能を評価できる。3 アスリートの代謝はスポーツ活動だけでなく栄養摂取とも関連する。4 アスリートの代謝と腸内細菌叢との関連が注目されている。(著者抄録)

過去の身体活動疫学に関する研究を網羅的に収集・精読するシステマティックレビュー、ならびに生活習慣病予防、癌予防、運動器障害や認知症の予防と身体活動・運動・体力との関係を客観的に分析したメタ解析の成果を紹介した。この研究成果を基に、厚生労働省の「運動基準・運動指針の改定に関する検討会」において、新しい基準・指針のあり方について方向性が示されたので、その論点と今後の活用のあり方について概説した。

運動種目（有酸素性運動やレジスタンス運動など）や身体活動強度などが動脈スティフネスに及ぼす影響について、自身の研究成果や先行研究を踏まえて概説した。

65歳以上の高齢者への「運動」介入が運動器の機能に関連するアウトカム改善に効果があるか否かについて、システマティックレビューを用いて検証した。高齢者に対する虚弱改善や介護予防において最も重要と考えたアウトカムであるADL、IADLを、運動介入によって改善させるか否かという視点では、効果を肯定的に示した文献数が少なく、一定の知見を得ることは困難と考えられた。しかし代理アウトカムでは、複合的な運動トレーニングにより転倒を減少させ得ること、十分な強度の筋力トレーニングであれば骨格筋量を増加させ得ること、特定の種目でなくとも十分な強度・頻度の運動介入により高齢者の膝痛の軽減が期待できること、が示唆された。(著者抄録)

運動習慣のある健康な高齢者において筋発揮張力維持法(LST)が身体諸機能(筋量・筋力、筋血流量、動脈硬化度)を改善させる効果が若年者同様に認められるかを、運動介入実験によって検証した。介入運動として、LSTトレーニングを実施する群と、通常高齢者に処方されることの多い低負荷トレーニングを実施する群の2群を無作為に設定した。また、筋肥大を促す生理的メカニズムの検証として介入運動期間中に、運動時の一過性の生理応答の観察を行った。高齢者においても12週間のLSTを用いた膝伸展・屈曲運動により若年男性同様、有意な筋肥大・筋力増強、安静時筋血流量の増加が起こることが示された。男女ともに大腿前・後の筋厚が有意に増加した。筋力増強効果をみるとLSTではすべての測定項目において有意な増加がみられた。

肝門脈血流量は運動強度に依存して低下した.運動時の門脈血流量と血管断面積間の単相関係数は高かった(r=0.812, p<0.01).門脈血流量に対して血流速度も単相関係数には有意性が認められた(r=0.375, p<0.05).門脈血流量に対する偏相関係数は,門脈本幹断面積が高かった(vs. cross-sectional area and vs. venous velocity, rxy・z=0.809 and rxz・y=0.301)

本実験の結果より,12週間の高強度インターバルトレーニングが健康で活動的な青年男子の左心室に及ぼす影響として, 1)拡張期左心室腔の拡大,心筋(心室中隔)肥大が起こること, 2)運動中に限り拡張期の左心室伸展性が増加し,それが運動中の一回拍出量の増加及び心拍数の低下に寄与していること, が示唆された

被験者は3名の健康な男子で,45分間,水温22°Cと30°Cの水道水の中,及び1%カルボキシメチルセルロースで粘性抵抗を高めた水の中を水中トレッドミルで歩行し,運動中の酸素摂取量と直腸温を測定した。水温30°Cにおいて直腸温は水道水及び粘性水で上昇した。直腸温の上昇率は粘性水が高い傾向にあった。水温22°Cにおいて直腸温は粘性水で上昇し,水道水で下降する傾向を示した。粘性水における酸素摂取量は水温30°C及び22°Cのどちらでも水道水より高かった。水温22°Cにおける酸素摂取量の増加率は,水温30°C時よりも低い傾向にあった。これらの結果は粘性水が熱放散を減少したことを示唆する。粘性水での水中歩行運動は体温を保持するので運動処方に効果的である

肝動脈結紮ラットを用いて肝の糖および脂質代謝に関して検討した。20m/分の速度で60分間のendurance runningに対してperformance,運動後の血清〔total-bilirubin〕,〔NEFA〕,〔TG〕には非肝動脈結紮ラットとの差は見られなかった。しかしながら肝動脈結紮により運動直後の血中〔glucose〕は,非肝動脈結紮ラットの160%になった。さらに肝コハク酸脱水素酵素(SDH)活性および血清〔total-ketone body〕の低下が観察された

平成30年度は全国の市町村から275件を以下のように無作為抽出し、調査を実施した。すなわち、政令指定都市のすべて（20件）、人口20万以上70 万人未満の都市の30％（30件）、人口5万以上20 万人未満の都市の20％（83件）、人口5万人未満の都市の10％（119件）、および東京23区すべて（23件）であった。調査対象数は抽出された市町村における6つの部門（健康、スポーツ、教育、都市計画、交通、環境）合計1,650件（275×6）であった。
調査項目は、①身体活動促進に関する行動計画の策定について（計画の名称、策定年度、内容および目標）、②行動計画の策定における部門・組織間の連携について、③計画策定の際の科学的根拠の利用について、④実際に行われた事業や活動について、⑤行動計画の実施における部門・組織間の連携について、⑥行動計画の事前評価と事後評価の実施についてであった。
調査方法は、対象として抽出された市町村の総務課宛てに調査依頼状を送付し、前述した6部門において「該当する地方計画の策定に関わった部署の担当者」が本調査に回答するように依頼した。この際、担当者の回答意欲を高めるために、これまでに我々が都道府県で実施した同様の調査の報告書を同封した。なお、調査方法はインターネットを介したWeb調査であった。
Web上で回答されたデータおよびインターネットや郵送で回収したデータを整理し、解析用データベースを作成した。このデータベースを使って記述統計処理を行った。

糞便量、形、色、および臭いは、病気、食習慣、腸内細菌叢に関連している。我々は包括的な糞便評価のためのカードを開発し妥当性を検証した。 38人の健康な成人で、カードを用いた便の体積、形態、色、臭いの観察は、重量計、水分計、硬度計、比色計、臭気測定計による客観的評価と比較した結果、糞便の量、形、および色は、多面的な評価カードによる観察で推定できる。また、健康な日本人722名を対象とした横断的研究により、腸内細菌群集構造は、現居住地域、運動習慣、座位時間、睡眠時間、カリウム・色の薄い野菜の摂取量、習慣的な排便頻度や採便当日の糞便の形状・色・量が関連することが明らかとなった。

本研究の主目的は、ゲノムワイド関連解析や候補遺伝子アプローチにより、瞬発系・パワー系運動能力および持久系運動能力を規定する遺伝子多型を同定することである。さらに、これらの多型の生理機能を解明することが第二の目的である。ゲノムワイド関連解析から、日本人における瞬発系・パワー系運動能力や持久系運動能力に関連する遺伝子多型を複数同定した。また、世界の筋力に関係する遺伝子多型を大規模解析から明らかにし、それに関連する多型の一部は日本人においても筋線維組成にも関連した。また、候補遺伝子アプローチから日本人の瞬発系・パワー系運動能力に関連する遺伝子多型や筋線維組成に関連する遺伝子多型を複数明らかにした。

健康な日本人男性506名を対象に，ヒトゲノム上に点在する約600万個の一塩基多型を分析した結果，49SNPsがp<1.00×10-5で検出された．それぞれピックアップされたSNPの中から，1つの遺伝子の中にあるSNPが複数ツリー上に上昇しているもので，偽陽性であるかどうかの確認を行い，Bioinfomaticな方法で確認しサルコペニアのリスクにたんぱく質の機能に関与する可能性を確認したところ，ESR1やMEGF10などが候補遺伝子として抽出された．現在は，これらの遺伝子のリスクスコアとサルコペニアとの関連について論文化しているところである．

本研究の目的は、身体活動量にどのような環境要因が影響を及ぼしているかを明らかにすることである。
最初に、空間疫学手法を用いて都道府県別の身体活動量を可視化した地図を作成し、人口が多い都道府県の歩数が多いことを確認した。次に、地域相関研究によって社会・自然環境と歩数の関係を調査した。歩数との間に有意な関係を観察したのは、都市公園数、自家用車数、年間積雪日数、年間平均気温、自家用車の増加率であった。さらに、コホート研究において、身体活動に関連する労働環境と糖尿病、腰痛、腎結石なのどの非感染性疾患罹患率の間に関連があることを明らかにした。

システム・ダイナミックスの定性モデルである因果ループ図を用いて、日本人の健康的な食事に寄与する構造的要因を検討した。日本人のヘルスリテラシーや日本の食料品価格の高さなど複数の要因が相互に影響を与えつつ、日本人の肥満者の割合が増加することを抑制している可能性を示した。
またシステム・ダイナミックスの定量モデルであるストック・フロー図を用いたシミュレーションモデルにより、健康寿命とケア期間（平均余命と健康寿命の差）の関連を検討した。高齢者において死亡率の減少よりむしろ自立から非自立に移行する変化率を下げることが、ケア期間の短縮に有効である可能性を明らかにした。

生活習慣に伴う健康問題は，全ての世代に共通した社会問題となっている．日常の交通行動は，こうした健康問題に多大な影響を及ぼす習慣的な身体活動であり，徒歩・自転車・公共交通など自動車以外の交通手段の利用促進は，交通問題だけでなく健康問題にも密接に関わるものである．本研究では，これまで個別に取り組まれてきた都市交通系と医療系の研究者が連携し，健康に配慮した交通行動誘発のための行動変容プログラムを構築し，ケーススタディとして神奈川県大和市の市役所職員と特定保健指導対象者を対象に実証実験と効果計測を行い，大規模な実務展開に向けた課題を明らかにした．

介護予防教室の終了後には多くの高齢者が運動を中止してしまう。そのため、本ランダム化比較試験では、運動日誌を用いたセルフモニタリングや支援者からのメッセージ等を含む郵送支援法により、長期的な運動継続が可能かどうかを検討した。運動継続は、筋力運動2セット/週以上、3.5 METs以上のウォーキング150分/週以上を満たす割合で評価した。3ヵ月間の運動教室終了から1年間の運動継続率は、郵送支援群（78名）で46.2%、非郵送支援群（78名）で6.4%であり（P < 0.001）、郵送支援を受けることにより長期的な運動継続が促される可能性が示唆された。

日本人男女（18-85歳，784名）を対象として，新規エストロゲン受容体である“G-protein Coupled Estrogen Receptor; GPER”遺伝子多型が動脈硬化度および運動による動脈硬化改善効果に及ぼす影響について検討した。rs3808350多型において，GG型を有する者の動脈硬化度は有意に低値であったが，運動による動脈硬化抑制効果にこの多型は関係しなかった。また，この多型はBMIや血中グルコース濃度と関連していた。以上より，GPER遺伝子多型（rs3808350）は，有酸素性作業能力の高低に関わらず，動脈硬化指数や血糖値などの冠危険因子に影響することが示された。

食欲を亢進するペプチドホルモンのグレリンは、主に胃で産生されるが、視床下部や辺縁系に作用して、食行動、食嗜好を規定する事が動物実験から示唆されている。私達もグレリン遺伝子多型が少数型ホモの肥満女性（約10％存在）に於いて、食事摂取量、エネルギー摂取量（肥満女性平均の約82％の値で、これは正常体重の女性並み）、脂質、肉類の摂取量などが少ない事から、彼女らが意外にも「小食」で食欲そのものも乏しく、蛋白質や脂質をあまり好まない事を明らかにした。私達は本研究で、彼女らの食べ物の絵に対する反応性が低いかを実際に光トポグラフィ（fNIRS）を用い測定。また彼女らは空腹時の総グレリン量が有意に少なかった。

＜研究の背景＞ Tripette博士は、多くの子どもや大人が夢中になっているテレビゲームの使用が私達の身体に及ぼす影響について研究した。
＜研究の方法＞ 2年間の研究期間に２つの研究を実施した。１）新型アクティブビデオビゲーム実施中のエネルギー消費量（メッツ値）定量に関する研究と２）アクティブビデオゲームの減量効果に関する研究である。１）では、30歳から50歳までの成人16名を研究参加者とし、ヒューマンカロリメーターを使用して、新型テレビゲーム（Wii Fit U）に新しく搭載されるゲーム実施中のエネルギー消費量をゲーム毎に定量した。２）では、20歳から64歳までの成人計53名を研究参加者とした、6週間の減量を目的うとした無作為割付介入研究を実施した。
＜研究実施の状況とその成果＞ １）Wii Fit Uの新しい18種目のゲームのメッツ値は、最も低いフラの2.2メッツから最も高いヒップホップの4.7メッツまでの範囲に分布した。18種目中7種目が低強度に、11種目が中強度に分類された。２）体重、腹囲、腰囲の減少量がWii Fit Plusを使用した介入群において対照群よりも有意に大きく、体重正味1.7kgの減少、腹囲正味1.8cmの減少が得られた。
＜まとめ＞ アクティブビデオゲームの使用は低強度～中強度の身体活動を伴い、習慣的な使用により減量効果が期待できることが示唆された。

我々は、533名の日本人中高齢女性を対象に、生活習慣病発症リスクに対するサルコペニアとメタボリックシンドロームの相互関係について横断的に検討した。その結果、サルコペニアとメタボリックシンドロームの合併は、動脈硬化の指標である脈波伝搬速度および糖尿病リスクであるHbA1cが相乗的に高まることが示された。
また動脈硬化リスクに対するADRB3 Trp64Arg遺伝子多型の多様性に体力レベルの違いが影響するかを横断的に検討した結果、体力の低い者はADRB3 Trp64Arg遺伝子多型による動脈硬化リスクの多様性に影響するが、体力の高い者は多型による影響がなくなる可能性が示された。

身体活動の個人差は大きい。それには、１）環境、２）遺伝や形質、さらに、３）疲労や感染、の違いが関連すると推測される。本研究では、①高強度身体活動の多寡は、染色体4番と染色体8番を中心に複数のSNPsと関連すること、②ミトコンドリアDNA多型は筋力や瞬発力と関連すること、③自宅近隣の買い物や生活に必要な環境が歩行や身体活動に関連すること、④TLR5を介した腸内免疫と腸内細菌叢の相互作用が身体活動の多寡に関連すること、などが示唆された。以上から、身体活動の多寡にはいくつかの内的ならびに外的な要因が関与し、免疫が身体活動に関与する可能性を初めて示唆した。

国内では虚血性心疾患,脳血管疾患などの動脈硬化を起因とする死亡原因が26%程度占めているため,いかにして,動脈硬化性疾患やそのリスクを軽減させるための生活習慣の改善を促せるかが重要な課題である。しかし,運動効果には,個人差があることから,動脈硬化に対する運動指導には個人対応型のテーラーメイド運動指導が必要であると考えられる。本研究では,動脈硬化指標と運動効果の個人差に影響を及ぼす血管拡張・収縮調整性因子の遺伝子多型を探索することを目的とした。被験者は,喫煙習慣はなく,慢性的な疾患を有しない,18～70歳までの男女763～843名を対象とし,5,10-methylenetetrahydrofolatereductase遺伝子多型(MTHFRC677T)やfatty-acidbindingprotein2遺伝子多型(FABP2Ala54Thr)をTaqman法にて判定し,動脈スティフネスの指標として頸動脈β-stiffnessおよび血圧を測定した。体力レベルは最大酸素摂取量を測定し,各年代・性別ごとの最大酸素摂取量の中央値を基準に体力の高い群(High-Fit群)と体力の低い群(Low-Fit群)に分けた。MTHFRC677TのTT型は,High-Fit,Low-Fit群ともに有意に高い血中ホモシステイン濃度を示した。Low-Fit群においてMTHFRC677TのTT型の頸動脈β-stiffnessはCCおよびCT型よりも有意に高値を示した(p<0.05)が,High-Fit群では多型間に差が認められなかった。一方,FABP2Ala54Thrの遺伝子多型間においては,Low-Fit群において,FABP2Ala54ThrのThr/Thr型と比較して,Ala/Ala型の頸動脈β-stiffness,収縮期血圧,拡張期血圧は有意に高値を示した(p<0.05)が,High-Fit群では,多型間で差が認められなかった。本研究の結果から,運動習慣のない者は,MTHFRC677TおよびFABP2Ala54Thr遺伝子多型による動脈硬化リスクの多様性に影響するため,継続的な運動の実施を指導する必要性がある可能性が示された。

本研究は肥満関連遺伝子の1つであるPPARγ2遺伝子のPro12AlaおよびC1431T多型と体力、体組成,メタボリックシンドロームリスクとの関連について横断的に検討した。被験者は、健康な日本人男女716名とした。測定項目は、メタボリックシンドローム関連指標(BMI、血糖値、血中脂質、血圧等)、体力、身体組成(DXA法)、及びPPARγ遺伝子多型であった。遺伝子多型はTaq-Man法により同定した。被験者は、年代別最大酸素摂取量の高い群と低い群の2群に分類し、さらにPPARγ遺伝子C1431T多型のCC群およびCT+TT群の2群に分類し、年齢を共変量とした2元配置分散分析により比較検討した。その結果、若年男性被験者の場合は、体力とPPARγ2遺伝子のC1431T多型はメタボリックシンドロームリスク(Z値)に対して有意な相互作用が認められた。しかし、この関係は、中高齢男性および女性では認められなかった。さらにPro12Ala多型については、どのグループにおいても体力、体組成,メタボリックシンドロームリスクとの有意な関連は認められなかった。本研究の結果から、肥満関連遺伝子の1つであるPPARγ2遺伝子のC1431T多型のCC多型を持つ若年男性が低体力の場合、メタボリックシンドロームリスクが増強することが示された。

本研究では、第1に心肺体力と中心動脈の粘弾性を、第2に有酸素性トレーニングが中心動脈の粘弾性に及ぼす影響を検討した。加齢に伴って増加する中心動脈の粘性は、心肺体力を高く保つことでその増加が押さえられることが明らかになった。しかしながら、実際に心肺体力を上げるために10週間の有酸素性トレーニングを行った結果、中心動脈の粘性に改善は見られなかった。したがって、10週間という短い期間でなく、比較的長期間の有酸素性トレーニングを実施することで、中心動脈の粘性が改善すると考えられる。

ホモシステイン分解酵素遺伝子(MTHFR)多型の一つである677C→Tの変異が、血中のホモシステインや動脈硬化のサロゲート指標である動脈のスティフネスに及ぼす影響を横断的に検討した。
(1)MTHFR677TT型の者はホモシステイン濃度ならびに動脈スティフネスが高値を示した。
(2)MTHFR677TT型の者のうち、3メッツ未満の低強度身体活動量が少ない者では、血中ホモシステイン濃度が有意に高い値を示した。
(3)MTHFR677TT型の者のホモシステイン濃度は、食事による葉酸摂取量が食事摂取基準で定められた推定平均必要量を満たす者では少ない者より有意に低値を示した。
(4)全身持久力の指標である最大酸素摂取量が高い者と低い者で比較したところ、ホモシステイン濃度は体力の違いによる差は見られなかったが、動脈スティフネスは体力の高い者ではTT型の遺伝子多型の者でもCC型やCT型の者と有意差がなかった。すなわち、持久的体力の高い者ではMTHFR677遺伝子の変異による動脈スティフネス増加が抑制されていることが示唆された。
これらの結果は、循環器疾患のリスクは遺伝の影響を強く受ける一方で、環境要因の改善により修飾されることを示唆している。これらの研究成果は、今後縦断的な介入研究により検討さ れる必要がある。

身体運動がメンタルヘルス改善効果をもたらすメカニズムを分子・細胞レベルにおいて実験動物及びヒトを対象として検討し、運動動処方プログラム開発のための基礎的資料を得ることを目的とした。長期間の運動トレーニング及び一過性の運動は、大脳皮質運動野における脳神経細胞の形態的、機能的変化を引き起こし、結果的にメンタルヘルスの改善がもたらされる可能性が考えられる。

ヒトが宇宙で滞在することによって生じる身体機能の減退を防ぐため, どのようなトレーニングが効果的であるのかについて地上モデルを用いて検討した。実験期間中に片脚に体重をかけないようにする宇宙滞在モデルを用いて, 高強度インターバルトレーニングを一日おきあるいは二日おき, 高強度インターバル+筋力トレーニングを一日おきに行った。その結果, 一日おきに高強度インターバル+筋力トレーニングを行うと筋力, 筋量, 呼吸循環系などの運動機能を全般的に維持できることが示された.

研究1:トレーニング実施者における脂質酸化能および身体活動量(横断的検討)
長期にわたって高強度のレジスタンストレーニングを実施してきたボディビルダーとパワーリフター、および対照群として一般健常者を対象として、脂質酸化能、基礎代謝量、二重標識水法による日常生活のエネルギー消費量などを測定した。レジスタンストレーニング実施者においては、基礎代謝量のみならず、日常生活の総エネルギー消費量が非常に大きく、身体活動レベルも日本人の標準的な値を越えていた。一方、二重標識水法の結果に基づいて直前から食事をコントロールした上で、ヒューマンカロリメーターで測定を実施したところ、脂質酸化能の指標であるRQ(呼吸商)に有意差はみられなかった。
研究2:トレーニングの継続による脂質酸化能および身体活動量への影響(介入実験)
レジスタンストレーニングが脂質酸化能および日常生活における身体活動に与える影響を検討するために、運動習慣のない男子大学生を対象として、約3ケ月間にわたるトレーニングを実施した。測定は、トレーニング期間の直前および直後の計2回で、日常生活における身体活動量は二重標識水法・基礎代謝量と3次元加速度計を用いて評価した。脂質酸化能の指標であるRQや睡眠時代謝量などは、入室前の食事をトレーニング前後で同じになるようにした上で、ヒューマンカロリメーターを用いて測定した。1日当たりのRQの変化について、対照群と比較して有意差はみられなかった。睡眠時代謝量や24時間のエネルギー消費量についても、変化量には群間差がみられなかった。
以上のように、厳密な実験計画のもとで実施した横断的検討および介入実験のいずれからも、脂質酸化量に対するレジスタンストレーニングの影響はみられなかった。ただし、個人差は大きいものの、職業などの影響により、日常生活における身体活動量の大きくなる傾向がみられた。

介護予防のための筋力向上を目的とした筋力トレーニングを中高年者が行う際の危険性が従来から指摘されていることに加えて、生活習慣病危険因子に対する影響は十分に明らかにされていない。我々の先行研究成果から、レジスタンストレーニングが動脈硬化度を増加させることが明らかとなった。そこで、動脈硬化度を増加させないレジスタンストレーニングの実施方法を検討するために介入研究を行った。39名の健康な男性被験者を高強度筋力トレーニング群、中強度筋力トレーニング群、有酸素運動と筋力トレーニングを行なうコンバインドトレーニング群の3群に無作為に分けた。高強度群と中強度群は80%もしくは50%1RM強度の6種目の筋トレを各セット疲労困憊に至るまで疲労困憊に至るまで、3セット、週3回、4ケ月実施し、コンバインド群は高強度筋力トレーニングと60%HRmax強度の有酸素トレーニングの組み合わせを週3回、4ケ月行なった。トレーニング期間終了後、4ケ月の脱トレ期間を置いた。全ての被験者の頸動脈の硬化度と前腕の内皮機能を介入前、4ケ月目、8ケ月目に測定した。高強度と中強度群では4ケ月目で有意に頸動脈硬化度が増加した。前腕の内皮機能は両群とも変化しなかった。一方、コンバインド群では、頸動脈硬化度が4ケ月で低下する傾向が見ら、前腕内皮機能は有意に増加した。3群とも脱トレ後の8ケ月目には介入前の値に戻った。全ての群で全身の筋力は有意に増加した。以上の結果から、筋トレと有酸素制トレーニングを同時に行なうコンバインドトレーニングは、筋トレだけを行なうことにより誘発される頸動脈硬化度の増加を予防することに加えて、内皮機能の改善を促し、筋力と持久力の両方を高めることができるため、介護と生活習慣病の予防を両立することができるトレーニング方法の一つであることが示唆された。以上の成果をもとに、成果をDVDにまとめた。

本研究では、運動が慢性ストレス症候群の生理機能に及ぼす影響を自律神経機能、呼吸循環系、脳機能の応答を指標として検討し、メンタルヘルス改善のための運動処方プログラムの開発を行うための基礎的資料を得ることを目的とした。呼吸循環系の研究では、中高齢者に対するコンバインドトレーニングすなわち有酸素性及び無酸素性トレーニングの実施がメンタルストレス、体力、頸動脈循環、生活習慣病の危険因子に及ぼす影響を明らかにし、高齢者のストレス、Quality of Life(QOL)、体力を維持・強化する運動の方法を検討することを目的とした。その結果、1)うつ尺度は習慣的な運動の実施により低下する傾向にあったがその変化は有意ではなかった。2)脚の筋力の指標である脚伸展パワーが約20%増加した。3)エネルギー代謝に関連する脚の血流量が約35%増加した。4)脳の血流量を示す頚動脈血流量が有意に約20%増加した。以上の結果から、複雑な運動模倣タスク、等尺性筋力トレーニング、水中での動的運動で構成される6ヶ月間のコンバインドトレーニングによって、筋力、脚血流、脳血流が増加することが示唆された。脳の生理的変化を検討した研究の結果、運動時には安静時に比べ、運動野、補足運動野、小脳、大脳基底核に有意な脳活動の上昇が認められた。実験室内での単純な自転車運動時でも記憶や動機付け、情動に深く関与する大脳基底核に活性が認められた。また、脳活動と末梢血中の基質濃度変化に相関が認められ、基質が間接的に運動時・後に起こる情動の変化に関与する可能性が示された。橋網様体の活動と運動時の乳酸濃度との間に有意な正の相関が認められた。扁桃体の活動がFFA濃度の増加と負の相関を示したことは、運動が情動を改善する一因になる可能性を示唆している。本結果は、身体運動が慢性ストレスに対する防御に有効な対策であることを示唆している。

水中運動に関する先行研究は,運動肢が水中であることがほとんどであった.今回,運動肢を水の外に設定することにより,水中にある身体に及ぼす影響を選択的に明らかにする環境設定を考案した.このことによりハンドエルゴメーターを用いた運動処方と評価方法に関する新しい知見を提供できるものと考えた.各被験者に対して,ヘルシンキ宣言の趣旨に沿って研究の目的,方法,期待される成果,不利益がないこと,危険性を十分排除した環境とすることについて十分な説明を行い,研究参加の同意を得た.目的を遂行するために以下の実験を設定した.『・水中と陸上におけるハンドエルゴメーター運動時の腹部大静脈横断面積の比較・水中ハンドエルゴメーター運動における運動強度の違いが腹部大静脈横断面積に及ぼす影響・水中ハンドエルゴメーター運動における水位の違いが腹部大静脈横断面積に及ぼす影響・水中立位時の腹部大静脈横断面積の変化・水中立位における下腿部阻血が腹部大静脈横断面積に及ぼす影響』.本研究は,次の知見を新しい知見として提供する.1.運動時の腹部大静脈横断面積は,陸上条件より水中条件において有意に大きいこと.2.腹部大静脈の形態変化は,水中運動時の運動処方の指標として妥当な評価方法であること.3.水中運動時の静脈還流量の変化は,水位に依存して変化すること.4.同一被験者の静脈還流量は,年間を通してほぼ一定であること.5.水圧下の静脈還流は,秒単位で適応すること.6.足浴は,運動中の血圧変動には大きく関与することはないこと.7.水温40℃の足浴は,リラクゼーション効果を促進させること.これらの新しい知見を運動処方へ適応すれば,水中運動は,予備の範疇で血液循環に対応できることを示し,負荷強度設定範囲に高い自由度を与えることができることを示唆する.

昨年度の研究において、加齢による動脈コンプライアンスの変化に筋力トレーニングが及ぼす影響を横断的手法により明らかにした。筋力トレーニング経験のない青年および中高年被験者34名と、ウエイトリフティングおよびパワーリフティングクラブ所属の青年および中高齢メンバー28名を被験者とし、循環器病の独立したリスクファクターである、左心室形態、頚動脈コンプライアンス、脈波速度による全身の動脈コンプライアンスを測定し、比較した。その結果、1)筋力トレーニングが加齢による中心動脈コンプライアンスの低下を促進すること、2)この中心動脈コンプライアンスの低下は求心性左心室肥大と関連することが示唆された。以上の知見は、持久的トレーニングが中心動脈コンプライアンスを増加させるという好ましい効果とは対照的であった。さらに本年度は、24名の青年を対象にして無作為割り付け,介入実験により筋力トレーニングが動脈コンプライアンスに及ぼす影響を検討した。その結果、1)4ヶ月の筋力トレーニングにより動脈コンプライアンスが低下すること、2)このコンプライアンス低下は4ヶ月の脱トレーニングにより筋トレ前のベースライン値に回復することが明らかとなった。今後、健康増進を目的とした筋力トレーニングの遂行のための適切なガイドラインを策定するためには、筋力トレーニングが様々なリスクファクターにどのような影響を及ぼすかについてより包括的なエビデンスを確立することが必要である。

最近の研究では、造血前駆細胞(幹細胞)が内皮細胞へと形質変換し、虚血損傷筋における血管の再構築に寄与するとの報告がされており、このことは血管の再構築や血管新生に造血システムが寄与する可能性を示唆するものである。また、加齢に伴い血管の再構築や毛細血管新生能が低下することも知られている。この知見をもとに「加齢による血管再構築能に造血前駆細胞由来の血管内皮細胞の減少が寄与する」と仮説した。この仮説をヒトを用いた実験系で検証する第一段階として、中高齢者と若年成人との末梢血中造血幹細胞数を比較した。仮説が妥当であれば、中高齢者の方が末梢血中造血幹細胞数が少ないはずである。
6名の中高齢者(40歳〜68歳)との6名の若年成人(20歳〜30歳)の起床時の末梢血中造血幹細胞数を比較した。末梢血中造血幹細胞数は中高齢者の方が有意に小さい値を示した。さらに、年齢と末梢血中造血幹細胞数との間に有意な負の相関が観察された。また、一過性の運動(40分間、80%Vo2max)によって末梢血中造血幹細胞数は増加することを昨年の報告書で報告した。中高齢者と若年性人で一過性の運動による末梢血中造血幹細胞数の増加の程度を比較したところその増加量には有意差は見られなかった。
以上の結果は、加齢により、骨髄における造血が低下したか、骨髄から末梢血中に造血幹細胞が放出されにくくなったことを示唆している。加齢によって末梢血中の造血幹細胞数が減少することで、様々な要因による血管壁内皮細胞の損傷からの修復能が低下する可能性が考えられる。

本研究では、来るべき高齢化社会を念頭に置いて「発育期における過度の運動トレーニング」が中高年以降の身体機能にいかに影響するかを知ることを目的として、運動生理学的見地から検討した。発育期における「過度のトレーニング」及び「種目限定・活動内容の限定」の影響が、スポーツ活動を行わなくなって以降の身体諸機能に及ぼす影響を呼吸循環系及び運動器系の生理機能を中心として検討することで得られた科学的データを基に、「生涯スポーツ」の見地からみた発育期の適切な運動処方プログラムを作成するための基礎的資料を提供することを具体的な目的とした。測定項目としては、一般的な形態計測に加え、全身持久力の指標とされる酸素摂取量、心エコーを利用した心機能測定等、従来は成人においてのみ、あるいは疾病を有する患者にのみ実施されてきた測定を行った。また、運動器に対する影響については3週齢より飼育を開始した雄性・雌性ラットを用いて骨及び骨格筋に対する長期運動トレーニング並びに脱トレーニングの影響を検討した。ラットの平均寿命は約2年から3年程度であり、骨格筋の発達の程度から生涯を4段階に分類することが可能となった。ラット骨格筋では生後3週齢の離乳期に多重神経支配が単一神経支配へと変化する(第1ステージ)。性成熟完成期(第2ステージ)。生後40週齢前後までの筋重量増加、筋力増加期(第3ステージ)。相対的骨格筋重量が低下する老化期(第4ステージ)。ラットのライフステージを直接ヒトに当てはめることは非常に困難であるが、ヒトにおける「発育期」はラットの場合、性成熟が完成する前後の第2から第3ステージにかけてと考えられる結果を得た。今後、実験動物のデータを発育期における児童、生徒に応用するために必要不可欠なタイムテーブルが作製され、動物実験の結果をヒトに外挿するための基礎的資料が得られた。

身体運動に伴う骨格筋の毛細血管増加のメカニズムを明らかにするために、筋収縮様力学刺激が内皮細胞の管腔形成にどのような影響を及ぼすかを明らかにすることを本研究の目的とした。ヒト大動脈由来内皮細胞をコラーゲンコートしたシリコン膜上に培養し付着させ、内皮細胞をそのシリコン膜とともに伸縮させながら培養した(フレクサ-セル、岩城硝子)。シリコン膜を13kPaの陰圧で約20%伸展させる刺激を毎日2時間ずつ、30回/分(3600回/日)の頻度で加えた。この伸縮刺激を加えながら培養した場合と通常の環境で培養した場合とで、細胞の遊走能、細胞骨格形態、プロテアーゼ活性を比較した。伸展刺激は遊走能を高め細胞内アクチンフィラメントの形態を変化させたが、プロテアーゼ活性には有意な影響を及ぼさなかった。このことから、伸展刺激により内皮細胞の血管基底膜分解能は影響を受けないが、内皮細胞骨格を変化させ遊走能を高めることが示された。従来、内皮細胞血管形成活性は線維芽細胞増殖因子(FGF)などによる化学的刺激によって促進・誘発されると考えられてきたが、本実験の結果は筋収縮のような力学的伸縮刺激も血管形成活性を部分的に促進することを示唆している。また、内皮細胞に力学的刺激を感受する仕組みが存在することが推測される。本法を応用して、力学的刺激の細胞内伝達や管腔形成と遺伝情報の関連を調べることによって、身体運動に伴う骨格筋の毛細血管増加のメカニズムを明らかにすることができると考えられる。

本研究では1)末梢循環機能の指標として脈波を利用することの妥当性を検討すること、2)脈波を用いて末梢循環機能老化速度の個人差について検討すること、3)生活環境の違いが脈波に及ぼす影響をあきらかにすること、の3点を目的とした。まず,脈波が末梢の血流動態を正確に反映しているか否か,血管の特性(弾性や抵抗)が脈波のどの部分に反映されるかについて調べた。脈波波形はドップラー血流計で測定した末梢血流プロファイルと一致することが明らかとなり,脈波から得られる情報が末梢循環を評価する生理的指標として妥当であることが示唆された。電気回路を用いたシミュレーションの結果,指尖脈波の頂上付近の波打ちの程度や最初の波の頂上に到達するまでの時間で動脈系の弾性を評価できる可能性が示唆された。これらの結果をもとに加速度脈波波系から新しい脈波指数を考案し、末梢循環機能の個人差について検討した。この指数は個人内変動が少なく個人差の検討に有効であり、従来の動脈硬化を診断する指標と関係が高かった。新しい脈波指数の年齢と有意な相関が見られ加齢に伴って大きくなるが、その偏差が加齢に伴って著しく大きくなった。すなわち、末梢循環機能はその老化速度に大きな個人差があることが示された。さらに、産業構造の変化が緩慢で生活循環の変化が少なかったある漁村と大都市の生活者の脈波指数を比較したところ、全ての年齢層を通じて漁村生活者の脈波指数は都市生活者よりも有意に小さかった。この結果は、長期に渡る生活環境の違いが末梢循環機能によく影響を及ぼすことを示唆している。

身体運動に伴う骨格筋の毛細血管増加のメカニズムを明らかにするために、筋収縮様力学刺激が内皮細胞の管腔形成にどのような影響を及ぼすかを明らかにすることを本研究の目的とした。ヒト大動脈由来内皮細胞をコラーゲンコートしたシリコン膜上に培養し付着させ、内皮細胞をそのシリコン膜をと共に伸縮させながら培養した(フレクサ-セル、岩城硝子)。シリコン膜を13kPaの陰圧で約20%伸展させる刺激を毎日5時間ずつ、30回/分(9000回/日)の頻度で加えた。この伸縮刺激を加えながら培養した場合と通常の環境で培養した場合とで、細胞の増殖や管腔形成を比較した。細胞増殖に両条件間で差は見られなかった。管腔形成は伸縮刺激を加えて培養した方が通常の培養法よりも有意に活発であった。従来、内皮細胞による管腔形成は繊維芽細胞増殖因子(FGF)などによる化学的刺激によって促進・誘発されると考えられてきたが、本実験の結果は筋収縮のような力学的伸縮刺激も内皮細胞管腔形成を促進することを示唆している。さらに、内皮細胞に力学的刺激を感受する仕組みが存在することが推測される。本法を応用して、力学的刺激の細胞内伝達や管腔形成と遺伝情報の関連を調べることによって、身体運動に伴う骨格筋の毛細血管増加のメカニズムを明らかにすることができると考えられる。