Background:

Energy intake (EI) from daily meals, corresponding to total energy expenditure (TEE), is essential for maintaining good physical condition and performance in athletes. Athletes who continue high-intensity training while consuming insufficient energy from their daily diet are at risk for health problems, such as iron deficiency anemia, endocrine dysfunction, and energy metabolism disorders.

Objectives:

This study aimed to examine the altered health risks in athletes when EI was increased to meet TEE from a daily diet.

Design:

Case series study with dietary intervention.

Methods:

Participants were six female long-distance runners classified as Tier 3. TEE was measured before the nutritional intervention using the doubly labeled water technique to determine the individual target EI and meal content during the intervention. The nutritional intervention was implemented for 6 weeks; sports dietitians provided weekly nutritional advice to each participant on how to eat to meet TEE, in addition to providing appropriate meals (breakfast and dinner) throughout the intervention period. Body composition measurements, resting metabolic rate (RMR) measurements, and blood tests were performed before and after the 6-week nutrition intervention.

Results:

A mean negative energy balance before the intervention in all participants (−548 kcal/day) improved to −31 kcal/day during the intervention. Carbohydrate intake improved to recommended levels (>7 g/kg body weight/day). Five participants were classified as having stage 1 anemia before the intervention, but the condition of four participants improved or was in a recovery process after the intervention. In addition, the suppression of RMR (21.8 and 24.2 kcal/kg fat-free mass/day) in two participants returned to the normal range.

Conclusion:

In this case series, consciously increasing daily EI from meals to meet TEE was associated with a favorable change in health risks, such as improved iron status, recovered from RMR suppression, and decreased cortisol levels. Additionally, practical nutritional advice from sports dietitians appeared to support athletes in overcoming EI challenges.

Registration:

Effect of the diet avoiding relative energy deficiency on physical condition in female long-distance runners. https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000055221;UMIN000048455

[Purpose] The Japan Sports Nutrition Association (JSNA) is an academic society that aims to contribute to people’s health and the development of sports in Japan.[Methods] After numerous communication and academic events, the JSNA and the Korean Society for Exercise Nutrition (KSEN) exchanged a Memorandum of Understanding (MoU) in 2018.[Results] Based on the MoU, the JSNA and KSEN organized academic exchange events until the Coronavirus Disease 2019 pandemic and subsequent travel restrictions and lockdowns.[Conclusion] After four years of the pandemic and the downgrading of Coronavirus Disease 2019 infection risk, it is hoped that academic exchanges between the societies will resume gradually and enhance members’ recognition of the cooperation between the JSNA and KSEN for active collaborations in the future.

令和元年国民健康栄養調査によると、20代女性の朝食欠食率は18.1%、30歳代では22.4%であり、若年勤労女性の約5名に1名が朝食を欠食している。朝食欠食は若年女性における除脂肪量の低値、骨密度の低下及び主観的体調不良など様々な健康問題に関連することから、糖代謝、脂質代謝及び鉄代謝不良など他の健康問題を誘発するリスクにもなり得ると考えられる。【目的】若年勤労女性を対象に朝食摂取習慣の有無と血液生化学指標との関連を明らかにすることとした。【方法】対象者は正常月経周期を有する若年勤労女性22名であり、朝食摂取群(n=11、年齢30±3歳、BMI20.6±1.8kg/m2)と朝食欠食群(n=11、年齢28±6歳、BMI20.2±1.6kg/m2)に分類した。調査項目は食事記録法によるエネルギー、栄養素及び食品群別摂取量、早朝空腹時の血液検査及び生体電気インピーダンス法による身体組成であり、2群間で各項目を比較した。【結果】朝食欠食群は朝食摂取群と比較してエネルギー(kcal/日)、たんぱく質(g/日)、炭水化物(g/日)及び穀類(g/日)の摂取量が有意に低値を示した。また血液生化学指標において朝食欠食群の血清フェリチン(ng/dL)及びMCH(pg)が有意に低値を示した。血清フェリチン<20ng/dL及びMCH<28.6pgを鉄欠乏のスクリーニングとすると両血中指標ともに朝食欠食群は朝食摂取群と比較してカットオフ値を下回る者の割合が高値を示した。【結論】朝食摂取習慣の有無は若年女性における鉄欠乏と関連することが示唆された。潜在性鉄欠乏は本邦の若年女性において罹患率の高い疾病の1つであり、様々な不定愁訴と関連することから、その予防策として朝食摂取の重要性を普及する必要がある。(著者抄録)

[Purpose] The current study aimed to determine the association between serum uncarboxylated osteocalcin (ucOC) levels and dietary vitamin K intake in female Japanese athletes.[Methods] The nutritional profile and food group intake of 52 Japanese female athletes were investigated using a digital photographic method with data obtained from 3-day dietary records. The food groups were categorized into 18 groups in line with the standard tables of food composition in Japan. Fasting blood samples were collected for serum ucOC levels, and dual-energy X-ray absorptiometry (DXA) evaluated body composition and bone parameters.[Results] The results showed that dietary vitamin K intake level was 235 ± 148 µg/day, and approximately 70% (n = 36) of participants consumed more than the adequate intake (AI) level, based on the Dietary Reference Intakes for Japanese females aged 18–29. Serum ucOC levels were negatively associated with daily vitamin K intake (r = −0.388, &lt;i&gt;P&lt;/i&gt; = 0.004) and calcium (r = −0.596, &lt;i&gt;P&lt;/i&gt; = 0.004) after adjusting for energy intake.[Conclusion] Our study revealed that serum ucOC levels were negatively associated with dietary vitamin K intake in female Japanese athletes. Serum ucOC levels reflected dietary vitamin K intake in female athletes. In summary, female athletes consume more vitamin K than the general population to maintain bone health. Furthermore, our results indicated that serum ucOC levels might be linked to dietary calcium intake.