Elite athletes frequently invest in the use of supplements to optimize their dietary regimens and enhance their athletic performance. However, unregulated and unplanned use of supplements can lead to adverse consequences, including anti-doping rule violations or health issues. Thus, athletes should verify their diets, consider scientific evidence, and take necessary precautions regarding supplements before use. To date, no study has explored whether athletes check these factors before using supplements. This study aimed to investigate supplement use using a questionnaire administered to 1,392 athletes (including candidate athletes) who participated in the Tokyo 2020 Olympic/Paralympic and Beijing 2022 Winter Olympic/Paralympic Games. Participants were categorized as follows: 1,040 participants in the Tokyo 2020 Olympic Games, 83 in the Tokyo 2020 Paralympic Games, 239 in the Beijing 2022 Winter Olympic Games, and 30 in the Beijing 2022 Winter Paralympic Games. We collected data on supplement use and gained further knowledge through interviews with the athletes. Approximately 70% of Tokyo 2020 Olympic/Paralympic and Beijing 2022 Winter Olympic athletes and approximately 50% of Beijing 2022 Winter Paralympians used supplements. Over 50% of athletes had not received a doctor's diagnosis or a dietitian's evaluation before supplement use. Moreover, only 50% of the athletes who used dietary supplements reviewed the scientific evidence for the dietary supplements before using them and justified their choice based on their own investigation, while those who did not use dietary supplements cited either a lack of need or fear of an anti-doping rule violation. Considering the holistic health and performance of athletes, as well as the risk associated with unregulated use, such as overdose and anti-doping rule violations, there is a need for nutritional education on supplement use for athletes and their entourages.

The “meal first” strategy is traditionally recommended for athletes' conditioning. However, the importance of the “meal first” principle has not been detailly well documented in athletes' lives. Supplement use has recently become a common part of athletes' diets, but unmonitored supplement use can cause negative consequences, such as anti-doping violations and health issues. Therefore, this review summarizes how the “meal first” strategy and planned supplement use are important for enhancing athletes’ health and performance. We believe that the “meal first” strategy is beneficial in terms of the following aspects: (1) consumption of multi-nutrients and other functional components simultaneously; (2) positive effects on psychological well-being; (3) contribution to athletes' health by way of mastication; and (4) less risk for anti-doping violations. Before supplement use, we recommend that athletes first verify their basic factors (e.g., diet, training, and sleep), given that the benefits of supplements are examined and demonstrated with the control of those factors. Otherwise, athletes cannot obtain maximal benefits from the supplements. In contrast, there are situations in which supplements in athletes' lives can be advantageous, such as (1) nutrient deficiency due to ongoing dietary characteristics; (2) interruption of meals due to disease; (3) inaccessibility of quality food during athletic travel; (4) difficulty preparing food due to societal restrictions associated with disasters or infection outbreaks; (5) having a meal before, during, or after exercise is difficult; and (6) achieving targeted intake of performance-enhancing ingredients is not practical. In summary, we emphasize that the “meal first” strategy is recommended for athletes' conditioning, but there are several contexts when supplement use can be more useful in athletes' lives.

Aerobic training (AT) is suggested to be an effective anti-aging strategy for skin aging. However, the respective effects of resistance training (RT) have not been studied. Therefore, we compared the effects of AT and RT on skin aging in a 16-week intervention in 61 healthy sedentary middle-aged Japanese women. Data from 56 women were available for analysis. Both interventions significantly improved skin elasticity and upper dermal structure, and RT also improved dermal thickness. After the training intervention, expression of dermal extracellular matrix-related genes was increased in normal human primary dermal fibroblasts. AT and RT had different effects on circulating levels of factors, such as cytokines, hormones in serum, and metabolites, and RT increased dermal biglycan (BGN). To our knowledge, this is the first report to show different effects of AT and RT on skin aging and identify the key factors involved in RT-induced skin rejuvenation.

Sleep quality (duration, efficiency, and latency) is directly associated with human health. An interventional study reported that the time of dinner influenced sleep latency, suggesting that it may also be associated with other sleep quality indices under free-living conditions. Therefore, we cross-sectionally examined the association between the time from dinner to bedtime (TDB) and sleep quality indices under free-living conditions in the young Japanese population. Based on the TDB, 264 participants were separated into three quantiles (T1, ≤3.79 h; T2, 3.80–4.94 h; T3, ≥4.95 h from dinner to bedtime). The T1 (mean ± standard error; 26.4 ± 2.2 min, p = 0.081) and T2 groups (30.8 ± 2.2 min, p = 0.001) showed longer sleep latency compared to the T3 group (19.6 ± 2.2 min), after adjusting for confounding factors. Sleep efficiency in the T1 group (77.5 ± 1.6%) tended to be greater than in the T3 group (72.1 ± 1.6%, p = 0.061), whereas sleep efficiency in the T2 group was not significantly different (77.0 ± 1.6%) from that in the T1 group. Therefore, shortened TDB was associated with prolonged sleep latency in free-living conditions. Meal timing, especially dinner, should be considered along with other sleep hygiene measures to improve human health.

Substantial evidence suggests an important role of liver function in brain health. Liver function is clinically assessed by measuring the activity of hepatic enzymes in the peripheral blood. Brain-derived neurotrophic factor (BDNF) is an important regulator of brain function. Therefore, we hypothesized that blood BDNF levels are associated with liver function and fibrosis. To test this hypothesis, in this cross-sectional study, we investigated whether serum BDNF concentration is associated with liver enzyme activity, aspartate aminotransferase (AST)/ alanine aminotransferase (ALT) ratio, and fibrosis-4 (FIB-4) index in middle-aged and older women. We found that serum BDNF level showed a significant positive association with ALT and γ-glutamyltranspeptidase (GGT) activity and negative association with FIB-4 index, and a trend of negative association with the AST/ALT ratio after adjustment for age. Additionally, these associations remained statistically significant even after adjustment for body mass index (BMI) and fasting blood glucose level. These results demonstrate associations of serum BDNF levels with liver enzymes and hepatic fibrosis-related indices, which may underlie liver-brain interactions.

Objective According to the stages of change, this study identified the association between dietary control self-efficacy and social support for healthy diets as factors influencing life skills acquisition in dietary habits among adolescents in Japan. Research design This cross-sectional study was conducted between April and May 2018 among eight high school baseball teams in Japan. Method Participants included 180 Japanese high school baseball players. Survey items evaluated life skills (dependent variables), self-efficacy's influence on dietary control, social support (explanatory variables), and stages of change. Hierarchical multiple regression analysis was used to reveal the associations. Results In the pre-action stage, although there was no significant association between the interaction of self-efficacy and social support on total life skills (β = 0.11, p = 0.158), a significant association was observed in the action/maintenance stage (β = 0.32, p < 0.05). The interaction between self-efficacy and social support showed a significant association with goal setting in the pre-action stage (β = 0.19, p < 0.05) and with communicating in the action/maintenance stage (β = 0.34, p < 0.05). Conclusion The acquisition of life skills amidst dietary situations can be facilitated by providing social support that considers self-efficacy in relation to dietary control, according to the stages of change.

Objective: The aim of this study was to observe the relationship of protein intake at each meal and daily total with change in lean tissue mass with progressive resistance exercise training (RET) in healthy middle-aged women. Methods: Twenty-two healthy Japanese women were recruited from Shiga Prefecture, Japan, and a supervised whole body RET program was conducted twice a week for 16 wk. The dietary intake was assessed using 3-d dietary records. Dual-energy x-ray absorptiometry was used to measure the whole body lean soft tissue mass (WLTM). Multiple regression analysis was performed to examine the relationship between the protein intake and RET-induced changes in the WLTM after adjusting for age, sleep quality, physical activity, and energy intake. Results: The 16-wk RET program caused a significant gain in the WLTM (1.46 +/- 0.45%, P = 0.004). Multiple regression analysis showed that the baseline protein intake at breakfast was negatively associated with the percent change in the WLTM (beta = -1.598; P = 0.022). Additionally, the percent change (beta = 0.624; P = 0.018) in protein intake at breakfast was positively associated with the percent change in WLTM. Conclusion: Increasing protein intake at breakfast may contribute to RET-induced muscle hypertrophy in middle-aged women, especially among those who habitually consume low-protein levels at breakfast. However, future studies with larger sample sizes are required to confirm the importance of protein intake at breakfast. (C) 2022 Elsevier Inc. All rights reserved.

Loss of appetite in the summer season leads to weight reduction, which subsequently affects sports performance. We investigated this issue in 94 high school freshmen baseball players at four high schools. The participants were divided into two groups: RICE (n=38), receiving nutritional education with provision of rice; CON (n=56), receiving nutritional education only. The study was conducted between May and August, which is considered the summer period in Japan. Analysis of covariance showed that body weight reduction in the RICE group was significantly diminished relative to the CON group (p<0.001). In addition, the RICE group showed higher intakes of rice (p=0.011), vegetables, and seaweed than the CON group (p<0.05, respectively). These results suggest that nutritional education with provision of rice helped to attenuate the reduction of food intake in summer, thus maintaining body weight. On this basis we conclude that nutritional education with provision of rice can be a beneficial approach for maintaining and enhancing sports performance among high school baseball players.

The Japanese government declared a state of emergency from 7 April to 25 May to limit people’s movement due to the coronavirus disease (COVID-19) pandemic. This pandemic negatively affects athletes’ body composition due to inactivity. Therefore, we compared the body composition data (i.e., fat-free mass (FFM) and fat mass (FM)), of 43 Japanese elite fencers (22 men, 21 women), in September 2019 for baseline, and of 21 (12 men, 9 women) who completed the following measurements in June 2020 (POST; immediately after rescinding the emergency state) and September 2020 (POST-4M; 4-months after rescinding the emergency state). Results at baseline indicate no significant differences in body compositions among fencing disciplines. We also confirmed no significant changes in body mass during the 1-year investigation period in either sex. There were no time-course changes in men’s FFM and FM; however, time-course changes in women’s FM were observed. Compared to the baseline, FM values were significantly higher at POST and then returned to baseline levels at POST-4M in women. In conclusion, the 2-month stay-at-home period due to COVID-19 negatively affected women’s FM changes, but not their FFM or men’s FM.

OBJECTIVES:Skipping breakfast prolongs the fasting state initiated after the last meal consumed the previous day and can have negative effects on muscle protein balance. The aim of this crossover trial was to examine the effects of skipping breakfast before a single bout of resistance exercise (RE) on muscle protein breakdown (MPB), as assessed using the urinary 3-methylhistidine/creatinine ratio (3-MH/Cr). METHODS:Thirteen healthy young men, who habitually consumed breakfast (21.8 ± 1.1 y of age), were assigned to eating breakfast (EB) and skipping breakfast (SB) conditions. Participants consumed meat-free diets throughout the 5-d experiment. On day 5, individuals in the EB group consumed breakfast (497 kcal) 2.5 h before RE (75% repetition maximum), whereas those in the SB group consumed the same meal after dinner. RESULTS:In the two-way analysis of variance, significant interactions were observed with blood insulin and free fatty acid levels, and the 3-MH/Cr ratio (P < 0.05). We confirmed a significantly greater decrease in the insulin level pre-RE (P < 0.001; d = 3.281), and increases in the free fatty acid level pre-RE (P < 0.001; d = 1.437) and post-RE (P = 0.013; d = 0.811) and the 3-MH/Cr ratio 6 (P < 0.001; d = 0.878) and 8 h (P < 0.001; d = 0.634) post-RE in the SB condition than in the EB condition. CONCLUSION:Eating breakfast before RE can be beneficial for MPB suppression. The importance of breakfast consumption in terms of positive muscle protein balance is emphasized on sports fields.

While daily protein intake has been reported to be essential for muscle regulation, the breakdown of daily protein intake in individuals is typically the lowest at breakfast and skewed towards dinner. Skewed protein intake pattern and inadequate protein intake at breakfast was reported to be a negative factor for muscle regulation, and no study has examined the effects of protein intake pattern at each meal on anabolic response such as muscle hypertrophy. PURPOSE: This study aimed to examine whether a protein-enriched meal at breakfast to achieve adequate protein intake at all 3 meals is more effective for muscle accretion compared to typical protein intake pattern, skewed protein intake towards dinner. METHODS: This 12-week, parallel-group randomized clinical trial included 26 men (means ± SEs; age, 20.8 ± 0.4 years; BMI, 21.8 ± 0.4 kg/m2). The participants were divided into 2 groups: HBR (n = 12), consuming a protein-enriched meal at breakfast to achieve adequate protein intake at all 3 meals; LBR (n = 14), consuming a provided meal at breakfast to achieve adequate protein intake at lunch and dinner. The participants performed 12-week supervised resistance training (RT) program 3 times/week (3 sets of 8-12 repetitions at 75-80% of one repetition maximum for 5 exercises). We used dual-energy X-ray absorptiometer to measure total fat-free mass (TotalFFM). RESULTS: No significant difference in TotalFFM was observed between the 2 groups at baseline (HBR vs LBR: 52.4 ± 1.3 vs 53.4 ± 1.2 kg). After completing the 12-week diet plan and RT program, both the groups gained significant TotalFFM (2.1 ± 0.2 kg, 4.0 ± 0.4%), with the HBR group having greater changes in TotalFFM than the LBR group [HBR vs LBR, 2.5 ± 0.3 vs 1.8 ± 0.3 kg; P = 0.056; cohen’s d = 0.795 (Large effect size)]. CONCLUSIONS: Protein-enriched meal at breakfast to achieve adequate protein intake at all three meals is more effective than skewed protein intake at dinner for RT-induced muscle hypertrophy. This work was supported by the Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research (no. 17H02183 to S. Fujita).

BACKGROUND:Although daily protein intake (PI) has been reported to be essential for regulating muscle mass, the distribution of daily PI in individuals is typically the lowest at breakfast and skewed toward dinner. Skewed protein intake patterns and inadequate PI at breakfast were reported to be negative factors for muscle maintenance. OBJECTIVES:This study examined whether a protein-enriched meal at breakfast is more effective for muscle accretion compared with the typical skewed PI pattern. METHODS:This 12-wk, parallel-group, randomized clinical trial included 26 men (means ± SEs; age: 20.8 ± 0.4 y; BMI: 21.8 ± 0.4 kg/m2). The "high breakfast" (HBR) group (n = 12) consumed a protein-enriched meal at breakfast providing a PI of 0.33 g/kg body weight (BW); their PI at lunch (0.46 g/kg BW) and dinner (0.48 g/kg BW) provided an adequate overall daily PI (1.30 g/kg BW/d). The "low breakfast" (LBR) group (n = 14) consumed 0.12 g protein/kg BW at breakfast; intakes at lunch (0.45 g/kg BW) and dinner (0.83 g/kg BW) yielded the same daily PI as in the HBR group. The participants performed supervised resistance training (RT) 3 times per week (75-80% 1-repetition maximum; 3 sets × 10 repetitions). DXA was used to measure the primary outcome variable, that is, total lean soft tissue mass (LTM). RESULTS:The total LTM at baseline did not differ between the HBR (52.4 ± 1.3 kg) and LBR (53.4 ± 1.2 kg) groups. After the intervention, increases in total LTM were significant in both groups, with that in the HBR group (2.5 ± 0.3 kg) tending to be greater than that in the LBR group (1.8 ± 0.3 kg) (P = 0.06), with a large effect size (Cohen d = 0.795). CONCLUSIONS:For RT-induced muscle hypertrophy in healthy young men, consuming a protein-enriched meal at breakfast and less protein at dinner while achieving an adequate overall PI is more effective than consuming more protein at dinner.This study was registered at University hospital Medical Information Network (UMIN) Clinical Trials Registry as UMIN000037583 (https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000042763).

BACKGROUND:Combining resistance exercise (RE) with nutrient intake stimulates muscle protein net balance. However, it is still unclear whether the optimal timing of nutrient intake is before or after RE, especially on muscle protein breakdown (MPB) for an augmented muscle anabolic response. The aim of this study was to investigate the effect of a substantial mixed meal (i.e., nutrient- and protein-dense whole foods) before or after RE, compared with RE without a meal on the acute response of MPB in a crossover-design study.METHODS:Eight healthy young men performed three trials: (1) meal intake before RE (Pre), (2) meal intake after RE (Post), and (3) RE without meal intake (No). Plasma insulin and 3-methylhistidine (3-MH), an MPB marker, were measured.RESULTS:Time course change in plasma insulin level after RE was significantly higher in the Post condition than in the Pre and No conditions. The area under the curve of 3-MH concentration was significantly lower in the Post condition than in the Pre and No conditions.CONCLUSIONS:These results suggest that a substantial mixed meal immediately after RE may effectively suppress MPB in the morning.

Resistance exercise transiently activates anabolic and catabolic systems in skeletal muscle. Leucine-enriched essential amino acids (LEAAs) are reported to stimulate the muscle anabolic response at a lower dose than whey protein. However, little is known regarding the effect of LEAA supplementation on the resistance exercise-induced responses of the anabolic and catabolic systems. Here, we conducted a randomized, double-blind, placebo-controlled, parallel-group comparison trial to investigate the effect of LEAA supplementation on mechanistic target of rapamycin complex 1 (mTORC1), the ubiquitin–proteasome system and inflammatory cytokines after a single bout of resistance exercise in young men. A total of 20 healthy young male subjects were supplemented with either 5 g of LEAA or placebo, and then they performed 10 reps in three sets of leg extensions and leg curls (70% one-repetition maximum). LEAA supplementation augmented the phosphorylation of mTORSer2448 (+77.1%, p < 0.05), p70S6KThr389 (+1067.4%, p < 0.05), rpS6Ser240/244 (+171.3%, p < 0.05) and 4EBP1Thr37/46 (+33.4%, p < 0.05) after resistance exercise. However, LEAA supplementation did not change the response of the ubiquitinated proteins, MuRF-1 and Atrogin-1 expression. Additionally, the mRNA expression of IL-1β and IL-6 did not change. These data indicated that LEAA supplementation augments the effect of resistance exercise by enhancing mTORC1 signal activation after exercise.

The purpose of the study was to examine the association of the frequencies of milk and dairy product consumption with subjective sleep quality during the training period in Japanese elite athletes. In this cross-sectional study, 682 Japanese elite athletes who were candidates for the 2016 Rio Olympic Games underwent medical evaluations at the medical center of The Japan Institute of Sports Sciences. Self-reported questionnaires were used to collect information on demographics and lifestyle (age, height, weight, sports, presence of milk allergy, smoking and drinking habits), subjective sleep quality (good, normal, or poor), bedtime, waking time, sleep duration, and frequencies of milk and dairy product consumption. Data from 679 athletes (379 men, 300 women) without milk allergy, were analyzed. Based on the frequencies of both milk and dairy product consumption, the athletes were divided into three groups: low (0-2 d/wk), middle (3-5 d/wk), and high (6-7 d/wk). Multiple logistic regression models showed that in comparison with the low milk consumption group, the middle [OR (95% CI): 0.48 (0.26-0.91)] and high groups [0.38 (0.21-0.71)] were significantly associated with a lower risk of decrease in subjective sleep quality (0: good, 1: normal or poor) only in women, after adjusting for possible confounders, such as smoking, drinking habits, and sleep duration. Accordingly, the present study elucidated that a greater frequency of milk consumption was significantly associated with a lower risk of decrease in subjective sleep quality, during training periods in women.

Protein intake of >0.24 g/kg of body weight (BW) at a single meal is necessary to maximize muscle protein synthesis in a young population. However, the association between the protein intake rate for three meals and muscle mass in the young population has not been evaluated. We hypothesized that a protein intake of >0.24 g/kg BW at all three meals is effective for maintaining muscle mass. Therefore, we cross-sectionally examined the association between protein intake at all three meals with muscle mass in 266 healthy young subjects (aged 21.4 ± 2.4 years). Subjects were divided into the AP group, which achieved protein intake >0.24 g/kg BW at all three meals; and the NP group, which did not. We calculated total fat-free mass (FFM) and appendicular fat-free mass (AppFFM) with dual-energy X-ray absorptiometry, and the percentage of total FFM (TotalFFM%) and appendicular FFM (AppFFM%) were calculated as the percentage of BW (%BW). We demonstrated that TotalFFM% (77.0 ± 0.5 vs. 75.2 ± 0.4%, p = 0.008) and AppFFM% (34.7 ± 0.3 vs. 34.1 ± 0.2%, p = 0.058) were higher in the AP than in the NP group. This finding suggests that achieving protein intake of >0.24 g/kg BW at all three meals is important for muscle mass maintenance in young populations.

Objectives: We examined whether the Mini Nutritional Assessment-Short Form (MNA (R)-SF) predicted mortality in 367 nursing home residents (82% women; mean age = 84.4 +/- 8.5 years) in Japan. Measurements: We examined participants' basic characteristics (sex, age, height, weight, and medical history), the Barthel index (BI), clinical dementia rating (CDR), and six items of the MNA (R)-SF. The association between the MNA (R)-SF and 30-month mortality was assessed using a Cox proportional regression analysis. Results: During the study, 157 (42.8%) participants died. MNA (R)-SF scores in the Survival group were significantly higher than in the Death group (9.4 +/- 2.1 vs. 8.4 +/- 2.3, respectively; p < .001). After adjusting for age, sex, history of aspiration pneumonia, BI, and CDR, MNA (R)-SF scores were significantly associated with 30-month mortality (hazard ratio: 0.89, 95% confidence interval: 0.82-0.97, p = .005). Conclusion: The MNA (R)-SF was an effective predictor of mortality among nursing home residents in Japan, even after adjusting for potential confounders. These results indicate that periodically evaluating nutritional status using the MNA (R)-SF, and nutritional interventions according to status, may result in maintenance and improvement of nutritional status, as well as lead to reduced mortality.