Introduction

There are no reports examining the time-of-day effect on team training sessions in the gym without airflow and air conditioning on thermal strain in the summer heat. We investigated this effect during badminton training sessions on a clear summer day.

Methods

Nine male high school badminton players (Mean ± SD; age 17.1 ± 0.6 y, height 171 ± 4 cm, body mass 59 ± 7 kg) completed two 2.5-h badminton training sessions in the gym without airflow and air conditioning. The training sessions were started at 0900 h (AM) and 1600 h (PM) on separate days in August. Skin temperatures (chest, triceps, thigh, calf), infrared tympanic temperature, heart rate, thermal sensation and rating of perceived exertion were recorded at rest and at regular intervals during the sessions.

Results

Indoor and outdoor environmental heat stress progressively increased in AM and decreased in PM during the sessions. Ambient temperature (AM 30.1 ± 0.9°C; PM 33.2 ± 1.0°C: P < 0.001) and wet-bulb globe temperature (AM 28.1 ± 0.5°C; PM 30.0 ± 0.9°C: P = 0.001) during the sessions in the gym were higher in PM than AM. Mean skin temperature (AM 34.2 ± 1.0°C; PM 34.7 ± 0.7°C: P < 0.001), infrared tympanic temperature (AM 37.8 ± 0.5°C; PM 38.1 ± 0.4°C: P = 0.001) and thermal sensation (AM 2.7 ± 1.4; PM 3.3 ± 1.0: P < 0.001) during the sessions were higher in PM than AM. Body heat storage (AM 159 ± 30 W·m⁻²; PM 193 ± 30 W·m⁻²: P < 0.05) was greater in PM than AM. There were no time-of-day differences in the average heart rate (AM 75 ± 4% age-predicted maximal heart rate; PM 76 ± 5 age-predicted maximal heart rate: P = 0.534), body mass loss (AM 0.6 ± 0.3 kg; PM 0.8 ± 0.2°C: P = 0.079), the volume of water ingested (AM 1.5 ± 0.1 L; PM 1.6 ± 0.3 L: P = 0.447) and rating of perceived exertion (AM 16 ± 2; PM 16 ± 3: P = 0.281).

Conclusions

This study indicates greater thermal strain in PM trial than in AM trial during team training sessions in the gym without airflow and air conditioning on a clear summer day. Therefore, athletes and coaches of indoor sports should perceive that athletes may be exposed to a greater risk for thermal strain in the late afternoon from 1600 h than in the morning from 0900 h during the sessions in the gym under these conditions.

Previous studies commonly utilized a multi-select checklist method to assess an athlete's ability to recognize true sports-related concussion (SRC) signs and symptoms (S&S) amongst incorrect distractor options. However, this may overinflate the evaluation of participants' knowledge since the multi-select method does not test athletes' ability to retrieve knowledge from their long-term memory. To test this hypothesis, an online survey was sent to registered members of the Japan Lacrosse Association (n=8,530) to examine differences in reported SRC S&S by an open-ended question and multi-select formats. We also examined whether previous exposure to SRC education and a history of SRC influenced athletes' SRC S&S knowledge. The number and proportions of responses by participants were calculated using descriptive statistics. Pearson's correlation was used to analyze the relationship between scores from two question formats. Unpaired sample t-tests were used to compare mean scores of each question format by previous SRC education and history of diagnosed SRC. Odds ratio was calculated to express the relationship between the proportion of correct answers by question format per symptom. The response rate of the survey was 35.9% (n=3,065) and revealed that scores from two question formats were correlated (r=0.34, 95%CI=0.31, 0.37; p<0.001). For both question formats, athletes with previous exposure to SRC education and a history of SRC reported a greater number of correct answers; however, the mean differences were trivial. In conclusion, researchers and clinicians should acknowledge the difference between multi-select (recognition) and open-ended (free recall) when assessing one's understanding of SRC and managing athletes with a suspected SRC.

This study aimed to analyze contents of publicly available resources on sports related concussion (SRC) for collegiate athletes in Japan. We identified eleven sport governing bodies that published SRC guidelines. Review of guidelines revealed information regarding SRC risk reduction strategies were particularly lacking in existing guidelines; therefore, further efforts in the improvement of SRC guidelines are warranted. Additionally, future SRC guidelines should be tailored to the rules and characteristics of each sport and more sport governing bodies should have means to distribute their guidelines to their membership and ensure latest evidence-based recommendations are delivered to stakeholders of the sport.

Epidemiological data from race walk and marathon events suggest that a high incidence rate of exertional heat illness is associated with high ambient temperature and relative humidity. The 2020 Summer Olympics in Tokyo was no exception, which led the organizing committee to relocate the race walk and marathon competitions to Sapporo, which was predicted to experience much milder heat. Nonetheless, during the Games, Sapporo recorded the highest daytime ambient temperature in the past 97 years, with consecutive days over 30°C from July 22nd to August 7th, 2021. Five events (men's and women's 20 km race walk, men's 50 km race walk, women's and men's marathon) were held in Sapporo from August 5th to August 8th, 2021. The percentage of athletes who did not finish (DNF) in each event was 8.8% in men's 20 km race walk, 20.3% in men's 50 km race walk, 8.6% in women's 20 km race walk, 17.1% in women's marathon and 28.3% in men's marathon. A total of fifty athletes were transferred to the athlete medical station: 28 athletes completed the race (i.e., collapsed after finish line), while 24 were DNF athletes transported from the course. Forty-eight (96%) of athletes who were admitted to the athlete medical station exhibited signs and symptoms of exertional heat illness. Two athletes diagnosed with exertional heat stroke and three athletes diagnosed with severe heat exhaustion (rectal body temperature &amp;gt;39.5°C with or without central nervous system disturbance) were cooled using whole-body cold water immersion at the heat deck located within the athlete medical station. All athletes who were cooled successfully recovered without any complications. These athletes required an average of 14 ± 9.4 min (range, 6–30 min) to cool their rectal temperature below 39°C. These results show the importance for event organizers to prepare strategies to keep athletes cool, such as an ample amount of ice and water to supply whole-body cold water immersion.

Limited literature has investigated epidemiology of sports-related fatalities during high school organizes sports in Japan. Therefore, the purposes of this study are to determine the frequency and incidence rate of sports-related fatalities in Japanese high schools by cause and sports, and to examine the type of on-site first responder. Insurance claim data of sports-related fatalities in Japanese high schools reported to Japan Sports Council Injury and Accident Mutual Aid Benefit System between 2009 and 2018 were retrieved as the primary data source. All fatalities were classified into direct or indirect type by the reported etiology and further categorized into cardiac-related, head and neck injury, exertional heat stroke (EHS), or other. Frequency and incidence rate were calculated by cause of death and sports, and incidence rates were expressed per 100,000 athlete-years (AY) with 95% confidence interval (CI). Information regarding first responder to the incident was also retrieved and examined by frequency. A total of 63 sports-related fatalities were analyzed. The overall incidence rate was 0.45 (95%CI = 0.25–0.65) per 100,000AY. The incidence rates of direct and indirect fatalities declined from 0.36 and 0.50 per 100,000AY to 0.28 and 0.00 per 100,000AY, respectively. The leading cause of deaths was cardiac-related (n = 30/63, 47.6%), followed by head and neck injury (n = 15/63, 23.8%) and EHS (n = 14/63, 22.2%). The number of fatalities was highest in male baseball (n = 12/63, 19.0%) and the incidence rate was highest in male judo (4.79 per 100,000 AY, 95%CI: 0.68–8.15). Coach was the most frequently reported first responder onsite (n = 52/63, 82.5%). Medically trained personnel were involved in onsite care in two cases (3.2%). In conclusion, the occurrence of sports-related fatalities has declined over time from 2009 to 2018. To deliver appropriate medical care onsite for better survival, employment of medically trained personnel should be promoted in high school sports setting in Japan.

Rapid advances in wearable technologies and real-time monitoring have resulted in major inroads in the world of recreational and elite sport. One such innovation is the application of real-time monitoring, which comprises a smartwatch application and ecosystem, designed to collect, process and transmit a wide range of physiological, biomechanical, bioenergetic and environmental data using cloud-based services. We plan to assess the impact of this wireless technology during Tokyo 2020, where this technology could help characterize the physiological and thermal strain experienced by an athlete, as well as determine future management of athletes during a medical emergency as a result of a more timely and accurate diagnosis. Here we describe some of the innovative technologies developed for numerous sports at Tokyo 2020 ranging from race walking (20 km and 50 km events), marathon, triathlon, road cycling (including the time trial event), mountain biking, to potentially team sports played outdoors. A more symbiotic relationship between sport, health and technology needs to be encouraged that harnesses the unique demands of elite sport (e.g., the need for unobtrusive devices that provide real-time feedback) and serves as medical and preventive support for the athlete's care. The implementation of such applications would be particularly welcome in the field of medicine (i.e., telemedicine applications) and the workplace (with particular relevance to emergency services, the military and generally workers under extreme environmental conditions). Laboratory and field-based studies are required in simulated scenarios to validate such emerging technologies, with the field of sport serving as an excellent model to understand and impact disease.

The Tokyo 2020 Olympic Games is expected to be among the hottest Games in modern history, increasing the chances for exertional heat stroke (EHS) incidence, especially in non-Acclimatised athletes/workers/spectators. The urgent need to recognise EHS symptoms to protect all attendees' health has considerably accelerated research examining the most effective cooling strategies and the development of wearable cooling technology and real-Time temperature monitoring. While these technological advances will aid the early identification of EHS cases, there are several potential ethical considerations for governing bodies and sports organisers. For example, the impact of recently developed cooling wearables on health and performance is unknown. Concerning improving athletic performance in a hot environment, there is uncertainty about this technology's availability to all athletes. Furthermore, the real potential to obtain real-Time core temperature data will oblige medical teams to make crucial decisions around their athletes continuing their competitions or withdraw. Therefore, the aim of this review is (1) to summarise the practical applications of the most novel cooling strategies/technologies for both safety (of athletes, spectators and workers) and performance purposes, and (2) to inform of the opportunities offered by recent technological developments for the early recognition and diagnosis of EHS. These opportunities are presented alongside several ethical dilemmas that require sports governing bodies to react by regulating the validity of recent technologies and their availability to all.

<sec>
<title>Objective</title>
To develop best-practice recommendations using thermal indices to determine work-to-rest ratios and facilitate further implementation of environmental monitoring for heat safety in secondary school athletics in the United States.


</sec>
<sec>
<title>Data Sources</title>
A narrative review of the current literature on environmental monitoring for heat safety during athletics was conducted by content experts. A list of action-oriented recommendations was established from the narrative review and further refined using the Delphi method.


</sec>
<sec>
<title>Conclusions</title>
Assessment of wet bulb globe temperature at the site of activity and throughout the duration of the event is recommended to assist clinicians and administrators in making appropriate decisions regarding the duration and frequency of activity and rest periods. Activity-modification guidelines should be predetermined and approved by stakeholders and should outline specific actions to be followed, such as the work-to-rest ratio, frequency and timing of hydration breaks, and adjustment of total exercise duration, equipment, and clothing. Furthermore, integration of exertional heat illness injury data with environmental condition characteristics is critical for the development of evidence-based heat safety guidelines for secondary school athletics. Athletic trainers play an essential role in conducting prospective injury data collection, recording onsite wet bulb globe temperature levels, and implementing recommendations to protect the health and safety of athletes.


</sec>

<sec id="sec001">
<title>Purpose</title>
The time-of-day variations in environmental heat stress have been known to affect thermoregulatory responses and the risk of exertional heat-related illness during outdoor exercise in the heat. However, such effect and risk are still needed to be examined during indoor sports/exercises. The current study investigated the diurnal relationships between thermoregulatory strain and environmental heat stress during regular judo training in a judo training facility without air conditioning on a clear day in the heat of summer.


</sec>
<sec id="sec002">
<title>Methods</title>
Eight male high school judokas completed two 2.5-h indoor judo training sessions. The sessions were commenced at 09:00 h (AM) and 16:00 h (PM) on separate days.


</sec>
<sec id="sec003">
<title>Results</title>
During the sessions, indoor and outdoor heat stress progressively increased in AM but decreased in PM, and indoor heat stress was less in AM than PM (mean ambient temperature: AM 32.7±0.4°C; PM 34.4±1.0°C, <italic>P</italic>&lt;0.01). Mean skin temperature was higher in AM than PM (<italic>P</italic>&lt;0.05), despite greater dry and evaporative heat losses in AM than PM (<italic>P</italic>&lt;0.001). Infrared tympanic temperature, heart rate and thermal sensation demonstrated a trial by time interaction (<italic>P</italic>&lt;0.001) with no differences at any time point between trials, showing relatively higher responses in these variables in PM compared to AM during the early stages of training and in AM compared to PM during the later stages of training. There were no differences between trials in body mass loss and rating of perceived exertion.


</sec>
<sec id="sec004">
<title>Conclusions</title>
This study indicates a greater thermoregulatory strain in the morning from 09:00 h than the late afternoon from 16:00 h during 2.5-h regular judo training in no air conditioning facility on a clear day in the heat of summer. This observation is associated with a progressive increase in indoor and outdoor heat stress in the morning, despite a less indoor heat stress in the morning than the afternoon.


</sec>

<sec>
<title>Context</title>
Sex, age, and wet-bulb globe temperature (WBGT) have been proposed risk factors for exertional heat stroke (EHS) despite conflicting laboratory and epidemiologic evidence.


</sec>
<sec>
<title>Objective</title>
To examine differences in EHS incidence while accounting for sex, age, and environmental conditions.


</sec>
<sec>
<title>Design</title>
Observational study.


</sec>
<sec>
<title>Main Outcome Measure(s)</title>
Using data from the Falmouth Road Race, a warm-weather 7-mi (11.26-km) running road race, we reviewed records from patients treated for EHS at medical tents. The relative risk (RR) of EHS between sexes and across ages was assessed with males as the reference population. Multivariate linear regression analyses were calculated to determine the relative contribution of sex, age, and WBGT to the incidence of EHS.


</sec>
<sec>
<title>Results</title>
Among 343 EHS cases, the female risk of EHS was lower overall (RR = 0.71; 95% confidence interval [CI] = 0.58, 0.89; P = .002) and for age groups 40 to 49 years (RR = 0.43; 95% CI = 0.24, 0.77; P = .005) and 50 to 59 years (RR = 0.31; 95% CI = 0.13, 0.72; P = .005). The incidence of EHS did not differ between sexes in relation to WBGT (P &amp;gt; .05). When sex, age, and WBGT were considered in combination, only age groups &amp;lt;14 years (β = 2.41, P = .008), 15 to 18 years (β = 3.83, P &amp;lt; .001), and 19 to 39 years (β = 2.24, P = .014) significantly accounted for the variance in the incidence of EHS (R2 = .10, P = .006).


</sec>
<sec>
<title>Conclusions</title>
In this unique investigation of EHS incidence in a road race, we found a 29% decreased EHS risk in females compared with males. However, when sex was considered with age and WBGT, only younger age accounted for an increased incidence of EHS. These results suggest that road race medical organizers should consider participant demographics when organizing the personnel and resources needed to treat patients with EHS. Specifically, organizers of events with greater numbers of young runners (aged 19 to 39 years) and males should prioritize ensuring that medical personnel are adequately prepared to handle patients with EHS.


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We investigated the validity of infrared tympanic temperature (IR-Tty) during exercise in the heat with variations in solar radiation. Eight healthy males completed stationary cycling trials at 70% peak oxygen uptake until exhaustion in an environmental chamber maintained at 30°C with 50% relative humidity. Three solar radiation conditions, 0, 250 and 500 W/m2, were tested using a ceiling-mounted solar simulator (metal-halide lamps) over a 3 × 2 m irradiated area. IR-Tty and rectal temperature (Tre) were similar before and during exercise in each trial (P > 0.05). Spearman's rank correlation coefficient (rs) demonstrated very strong (250 W/m2, rs = 0.87) and strong (0 W/m2, rs = 0.73; 500 W/m2, rs = 0.78) correlations between IR-Tty and Tre in all trials (P < 0.001). A Bland-Altman plot showed that mean differences (SD; 95% limits of agreement; root mean square error) between IR-Tty and Tre were - 0.11°C (0.46; - 1.00 to 0.78°C; 0.43 ± 0.16°C) in 0 W/m2, - 0.13°C (0.32; - 0.77 to 0.50°C; 0.32 ± 0.10°C) in 250 W/m2 and - 0.03°C (0.60; - 1.21 to 1.14°C; 0.46 ± 0.27°C) in 500 W/m2. A positive correlation was found in 500 W/m2 (rs = 0.51; P < 0.001) but not in 250 W/m2 (rs = 0.04; P = 0.762) and 0 W/m2 (rs = 0.04; P = 0.732), indicating a greater elevation in IR-Tty than Tre in 500 W/m2. Percentage of target attainment within ± 0.3°C between IR-Tty and Tre was higher in 250 W/m2 (100 ± 0%) than 0 (93 ± 7%) and 500 (90 ± 10%; P < 0.05) W/m2. IR-Tty is acceptable for core temperature monitoring during exercise in the heat when solar radiation is ≤ 500 W/m2, and its accuracy increases when solar radiation is 250 W/m2 under our study conditions.

<p>This study aimed to investigate Catastrophic injuries as defined by Japan Sport Council (JSC) (grades I-XIV) documented on school campus and explore benefits of introducing athletic trainers on campus. All injury data submitted to JSC Injury and Accident Mutual Aid Benefit System between 2009 -2018 that occurred in junior high or high school (n=2,094) were included in the analysis. Injury data were categorized by activity (curricular course, curricular activity, school event, extracurricular activity, recess, other) and location (classroom, laboratory, indoor athletic facility, hallway, staircase, balcony, rooftop, restroom, outdoor athletic field, pool, other). </p><p>Athletic injuries were documented in 98%, 86%, and 71% of all injuries that occurred during extracurricular activity, curricular course, and school event. In addition, 93%, 90%, and 96% of all injuries that occurred at outdoor athletic field, indoor athletic facility, and pool, respectively, were related to athletic activity.</p><p>JSC data suggest that majority of injuries that occur on junior high and high school campus were related to athletic activities. Therefore, school administrators may benefit from having athletic trainers who can provide first aid and injury prevention services to help elevate the standard of care on school campus.</p>

Our study describes youth football (YFB) environmental conditions and the associated heat index (HI) risk category. An observational research design was utilized. Independent variables included month, time, event, and geographic location. Main outcome variables were frequency of events, average HI, and corresponding risk categorization. The HI was recorded with the day and time for each YFB event across 2 YFB seasons. Nearly half (49.8%) of events were in a high HI risk category and 20.0% should have been cancelled. The hottest HI values were recorded in July and August (83.2 +/- 9.4 degrees F to 87.2 +/- 10.9 degrees F; 24.0% of YFB events). The 7 to 10 am time frame was cooler (67.7 +/- 14.5 degrees F; 6.3% of YFB events) than other time frames (P &lt; .001). Hotter HI values were recorded in practices versus games (75.9 +/- 14.1 degrees F vs 70.6 +/- 14.6 degrees F; t = -6.426, P &lt; .001). Starting the YFB season in September and holding weekend events in the early morning hours can decrease exposure to environmental heat stress.

Context: Recent case reports on malignant hyperthermia (MH)-like syndrome in physically active populations indicate potential associations among MH, exertional heat stroke (EHS), and exertional rhabdomyolysis (ER). However, an expert consensus for clinicians working with these populations is lacking.
Objective: To provide current expert consensus on the (1) definition of MH; (2) history, etiology, and pathophysiology of MH; (3) epidemiology of MH; (4) association of MH with EHS and ER; (5) identification of an MH-like syndrome; (6) recommendations for acute management of an MH-like syndrome; (7) special considerations for physically active populations; and (8) future directions for research.
Setting: An interassociation task force was formed by experts in athletic training, exercise science, anesthesiology, and emergency medicine. The ''Round Table on Malignant Hyperthermia in Physically Active Populations'' was convened at the University of Connecticut, Storrs, September 17-18, 2015.
Conclusions: Clinicians should consider an MH-like syndrome when a diagnosis of EHS or ER cannot be fully explained by clinical signs and symptoms presented by a patient or when recurrent episodes of EHS or ER (or both) are unexplained. Further research is required to elucidate the genetic and pathophysiological links among MH, EHS, and ER.

Study objective: We investigated the efficacy of tarp-assisted cooling as a body cooling modality.
Methods: Participants exercised on a motorized treadmill in hot conditions (ambient temperature 39.5 degrees C [103.1 F], SD 3.1 degrees C [5.58 F]; relative humidity 38.1% [SD 6.7%]) until they reached exercise-induced hyperthermia. After exercise, participants were cooled with either partial immersion using a tarp-assisted cooling method (water temperature 9.20 degrees C [48.56 F], SD 2.81 degrees C [5.06 F]) or passive cooling in a climatic chamber.
Results: There were no differences in exercise duration (mean difference=0.10 minutes; 95% CI-5.98 to 6.17 minutes or end exercise rectal temperature (mean difference=0.10 degrees C [0.18 degrees F]; 95% CI-0.05 C to 0.25 degrees C [-0.09 degrees F to 0.45 degrees F] between tarp-assisted cooling (48.47 minutes [SD 8.27 minutes]; rectal temperature 39.73 degrees C [103.51 degrees F], SD 0.27 degrees C [0.49 degrees F]) and passive cooling (48.37 minutes [SD 7.10 minutes]; 39.63 degrees C [103.33 degrees F], SD 0.40 C [0.72 degrees F]). Cooling time to rectal temperature 38.25 degrees C (100.85 degrees F) was significantly faster in tarp-assisted cooling (10.30 minutes [SD 1.33 minutes]) than passive cooling (42.78 [SD 5.87 minutes]). Cooling rates for tarp-assisted cooling and passive cooling were 0.17 degrees C/min (0.31 degrees F/min), SD 0.07 degrees C/min (0.13 degrees F/min) and 0.04 degrees C/min (0.07 degrees F/min), SD 0.01 C/min (0.02 degrees F/ min), respectively (mean difference=0.13 degrees C [0.23 F]; 95% CI 0.09 C to 0.17 degrees C [0.16 degrees F to 0.31 degrees F]. No sex differences were observed in tarp-assisted cooling rates (men 0.17 degrees C/min [0.31 F/min], SD 0.07 degrees C/min [0.13 F/min]; women 0.16 degrees C/min [0.29 degrees F/min], SD 0.07 degrees C/min [0.13 degrees F/min]; mean difference=0.02 degrees C/min [0.04 degrees F/min]; 95% CI-0.06 C/min to 0.10 degrees C/min [-0.11 degrees F/min to 0.18 degrees F/min]). Women (0.04 degrees C/min [0.07 degrees F/min], SD 0.01 degrees C/min [0.02 degrees F/min]) had greater cooling rates than men (0.03 degrees C/min [0.05 F/min], SD 0.01 degrees C/min [0.02 degrees F/min]) in passive cooling, with negligible clinical effect (mean difference=0.01 degrees C/min [0.02 F/min]; 95% CI 0.001 degrees C/min to 0.024 degrees C/ min [0.002 degrees F/min to 0.04 degrees F/min]). Body mass was moderately negatively correlated with the cooling rate in passive cooling (r=-0.580) but not in tarp-assisted cooling (r=-0.206).
Conclusion: In the absence of a stationary cooling method such as cold-water immersion, tarp-assisted cooling can serve as an alternative, field-expedient method to provide on-site cooling with a satisfactory cooling rate.

Objectives: The purpose of this study was to examine the relationship between pacing, gastrointestinal temperature (T-GI), and percent body mass loss (%BML) on relative race performance during a warm weather 11.3 km road race.
Design: Observational study of a sample of active runners competing in the 2014 Falmouth Road Race.
Methods: Participants ingested a T-GI pill and donned a GPS enabled watch with heart rate monitoring capabilities prior to the start of the race. Percent off predicted pace (%OFF) was calculated for seven segments of the race. Separate linear regression analyses were used to assess the relationship between pace, T-GI, and %BML on relative race performance. One-way ANOVA was used to analyse post race T-GI (&gt;= 40 degrees C vs &lt;40 degrees C) on pace and %OFF.
Results: Larger %BML was associated with faster finish times (R-2 = 0.19, p = 0.018), faster average pace (R-2 = 0.29, p = 0.012), and a greater %OFF (R-2 = 0.15, p = 0.033). %OFF during the first mile (1.61 km) significantly predicted overall finish time (R-2 = 0.64, p &lt; 0.001) while %OFF during the second mile (3.22 km) (R-2 change = 0.18, p &lt; 0.001) further added to the model (R-2 = 0.82, p &lt; 0.001). Body temperature (pre race T-GI and post race T-GI) was not predictive of overall finish time (p &gt; 0.05). There was a trend in a slower pace (p = 0.055) and greater %OFF (p = 0.056) in runners finishing the race with a T-GI &gt; 40 degrees C.
Conclusions: Overall, finish time was influenced by greater variations in pace during the first two miles of the race. In addition, runners who minimized fluid losses and had lower T-GI were associated with meeting self-predicted goals. (C) 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Objectives: To examine the effects of hydration and hand cooling on lowering body temperature after exercise in the heat.
Design: Randomized cross-over design.
Methods: Nine recreationally active male participants (mean +/- SD; age, 24 +/- 4; height, 177.3 +/- 9.9 cm; body mass, 76.7 +/- 11.6 kg; body fat, 14.7 +/- 5.8%) completed a bout of treadmill exercise in a hot environment. After completion of exercise, participants were assigned to the following trials for post-exercise cooling: (1) hydrated with passive rest (HY), (2) hydrated with hand cooling on both hands (HY+2HC), (3) dehydrated with passive rest (DY), and (4) dehydrated with hand cooling on both hands (DY+2HC). Within subject differences were assessed using a three-way (Hydration x Condition x Time) repeated measures ANOVA with Tukey's post hoc analysis if significant interactions were found.
Results: Irrespective of hydration status, hand cooling on both hands resulted in significantly greater reductions in T-REC than passive cooling at minute 20 (0.27 degrees C [0.05, 0.49], ES = 2.08, p=0.017) (Fig. 1). The reduction in T-REC at minute 18 trended towards statistical significance (0.21 degrees C [.003, .42], ES = 1.59, p=0.053). Hydration status alone and when differentiated among modes of cooling showed no differences on changes of T-REC or heart rate across all conditions during post exercise recovery (p&gt;0.05).
Conclusions: Hand cooling on both hands reduced T-REC more than passive cooling, however, the cooling rates observed render hand cooling a poor option for cooling. Greater reductions in T-REC after exercise or between bouts of exercise may enhance recovery and subsequent performance. (C) 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Context: Although body cooling has both performance and safety benefits, knowledge on optimizing cooling during specific sport competition is limited. Objectives: To identify when, during sport competition, it is optimal for body cooling and to identify optimal body-cooling modalities to enhance safety and maximize sport performance. Evidence Acquisition: A comprehensive literature search was conducted to identify articles with specific context regarding body cooling, sport performance, and cooling modalities used during sport competition. A search of scientific peer-reviewed literature examining the effects of body cooling on exercise performance was done to examine the influence of body cooling on exercise performance. Subsequently, a literature search was done to identify effective cooling modalities that have been shown to improve exercise performance. Evidence Synthesis: The cooling modalities that are most effective in cooling the body during sport competition depend on the sport, timing of cooling, and feasibility based on the constraints of the sports rules and regulations. Factoring in the length of breaks (halftime substitutions, etc), the equipment worn during competition, and the cooling modalities that offer the greatest potential to cool must be considered in each individual sport. Conclusions: Scientific evidence supports using body cooling as a method of improving performance during sport competition. Developing a strategy to use cooling modalities that are scientifically evidence-based to improve performance while maximizing athlete's safety warrants further investigation.

Context: Evidence-based best practices for the recognition and treatment of exertional heat stroke (EHS) indicate that rectal thermometry and immediate, aggressive cooling via cold-water immersion ensure survival from this medical condition. However, little is known about the recovery, medical follow-up, and return to activity after an athlete has suffered EHS. Objective: To highlight the transfer of evidenced-based research into clinical practice by chronicling the treatment, recovery, and return to activity of a runner who suffered an EHS during a warm-weather road race. Design: Case study. Setting: Warm-weather road race. Participant: 53-y-old recreationally active man. Intervention: A runner's treatment, recovery, and return to activity from EHS and 2014 Falmouth Road Race performance. Main Outcomes: Runner's perceptions and experiences with EHS, body temperature, heart rate, hydration status, exercise intensity. Results: The runner successfully completed the 2014 Falmouth Road Race without incident of EHS. Four dominant themes emerged from the data: predisposing factors, ideal treatment, lack of medical follow-up, and patient education. The first theme identified 3 predisposing factors that contributed to the runner's EHS: hydration, sleep loss, and lack of heat acclimatization. The runner received ideal treatment using evidence-based best practices. A lack of long-term medical care following the EHS with no guidance on the runner's return to full activity was observed. The runner knew very little about EHS before the 2013 race, which drove him to seek knowledge as to why he suffered EHS. Using this newly learned information, he successfully completed the 2014 Falmouth Road Race without incident. Conclusions: This case supports prior literature examining the factors that predispose individuals to EHS. Although evidence-based best practices regarding prompt recognition and treatment of EHS ensure survival, this case highlights the lack of medical follow-up and physician-guided return to activity after EHS.

Context: It has been well established that gastrointestinal temperature (T-GI) tracks closely with rectal temperature (T-REC) during exercise. However, the field use of T-GI pills is still being examined, and little is known about how measurements obtained using these devices compare during recovery after exercise in warm weather.
Objective: To compare T-GI and T-REC in runners who completed an 11.3-km warm-weather road race and determine if runners with higher T-GI and T-REC present with greater passive cooling rates during recovery.
Design: Cross-sectional study.
Setting: Field.
Patients or Other Participants: Thirty recreationally active runners (15 men, 15 women; age = 39 +/- 11 years, weight = 68.3 +/- 11.7 kg, body fat = 19.2%+/- 5.0%).
Main Outcome Measure(s): The T-GI and T-REC were obtained immediately after the race and during a 20-minute passive rest at the 2014 Falmouth Road Race (heat index = 26.2 degrees C +/- 0.9 degrees C). Temperatures were taken every 2 minutes during passive rest. The main dependent variables were mean bias and limits of agreement for T-GI and T-REC, using Bland-Altman analysis, and the 20-minute passive cooling rates for T-GI and T-REC.
Results: No differences were evident between T-GI and T-REC throughout passive rest (P = .542). The passive cooling rates for T-GI and T-REC were 0.046 +/- 0.031 degrees C.min(-1) and 0.060 +/- 0.036 degrees C.min(-1), respectively. Runners with higher T-GI and T-REC at the start of cooling had higher cooling rates (R = 0.682, P &lt; .001 and R = 0.54, P = .001, respectively). The mean bias of T-GI during the 20-minute passive rest was -0.06 degrees C +/- 0.56 degrees C with 95% limits of agreement of 61.09 degrees C.
Conclusions: After participants completed a warm-weather road race, T-GI provided a valid measure of body temperature compared with the criterion measure of T-REC. Therefore, T-GI may be a viable option for monitoring post-exercise-induced hyperthermia, if the pill is administered prophylactically.

関東大学女子ラクロスリーグ1部に所属する某大学の選手を対象に調査した。調査期間は2010年4月から2012年3月までの2年間とし、対象人数は1年目が46名、2年目55名で、調査項目は傷害の部位・種類・原因などとした。傷害の部位は「足関節」が最も多く、次いで「膝関節」、「大腿部」、「下腿部」の順であり、下肢の傷害が全体の7割以上を占めていた。傷害の種類は「捻挫」が最も多く、次いで「筋肉痛/スパズム」、「腱炎/腱周囲炎」、「打撲/血腫/挫傷」の順であった。傷害の原因は「使いすぎ」が最も多く、次いで「非接触型損傷」、「接触型損傷」であった。ポジション別にみると、傷害発生数が最も多いポジションは「ミッドフィルダー」であり、選手一人あたりの傷害発生数が最も多いポジションは「アタッカー」であった。