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Glycine, the simple amino acid, is a key component of muscle metabolism with proven cytoprotective effects and hypothetical benefits as a therapeutic nutrient. Cell, in vitro, and animal studies suggest that glycine enhances protection against muscle wasting by activating anabolic pathways and inhibiting proteolytic gene expression. Some evidence indicates that glycine supplementation may enhance peak power output, reduce lactic acid accumulation during high-intensity exercise, and improve sleep quality and recovery. This literature review critically explores glycine's potential as an ergogenic aid and its relevance to muscle regeneration, muscle strength, endurance exercise performance, and sleep quality. It also underscores key areas for future research. It is concluded that more randomized controlled clinical trials in humans are needed to confirm glycine's potential as a dietary supplement to support muscle function, recovery, and overall athletic performance as an ergogenic aid and to establish nutritional recommendations for athletic performance. Also, it is essential to consider that high doses (>500 mg/kg of body mass) could induce cytotoxic effects and contribute to acute glutamate toxicity.

Internationally, few studies have been written on the prevalence of eating disorders among rowers, and there is no research on the subject in Hungary. This is particularly important in weight-related sports such as rowing. The aim of this study is to assess the prevalence of eating disorders among rowers. A quantitative cross-sectional study was conducted in the summer of 2023. In a non-random convenience sampling, our target population consisted of certified competitive rowers (n = 222). In addition to socio-demographic, performance-related questions, the anonymous, self-completed questionnaire used the validated The Eating Disorder Inventory (EDI). Results were considered significant when p < 0.05. A total of 57 lightweight (25.67%) and 165 openweight (74.33%) rowers participated in the study. On the perfectionism subscale and the interoceptive awareness subscale, rowers competing in the lightweight category scored significantly higher (p = 0.03; p = 0.05). Scores on the EDI subscales, gender and BMI data did not show significant relationships. Overall, rowers in the openweight group scored higher on the bulimia subscale, but no rowers who met all criteria and could be identified as having eating disorders. Rowers who have only competed in national championships and not in international competitions were more likely to reduce stress levels by eating. The study showed that the prevalence of eating disorders among rowers is no higher than in the general population. However, continued assessment, further extensive research and education of rowers is essential in this area, as weight-related sports will always be a risk group for eating disorders.

The incorporation of triaxial accelerometers into Global Positioning Systems (GPS) has significantly advanced our understanding of accelerations in sports. However, inter-positional differences are unknown. This study aimed to explore the variability of acceleration and deceleration (Acc) distribution curves according to players' positions during soccer matches. Thirty-seven male players from a national-level Portuguese club were monitored using 10 Hz GPS with an embedded accelerometer during the 2021/2022 season. Resultant Acc was obtained from the x (lateral), y (frontal/back), and z (vertical) axes and expressed in gravitational units (g). Statistical Parametric Mapping was employed to compare playing positions: central defenders (CD), fullbacks (FB), central midfielders (CM), wide midfielders (WM), and strikers (ST). All positions exhibited a decreasing Acc distribution curve, very similar in shape, with a high frequency of events in the lower ranges (i.e., 0 to 1 g) and a lower frequency of events in the higher values (2 to 10 g). Post hoc comparisons revealed significant differences between all positions, except between FB and WM. Out of 1000 points in the curve, CD had 540, 535, 414, and 264 different points compared to FB, CM, WM, and ST, respectively. These findings indicate that players in different positions face distinct demands during matches, emphasizing the need for position-specific Acc analysis and training programming. By analyzing Acc as a continuous variable, this study highlights the importance of individualized monitoring to ensure the comprehensive and precise tracking of all player activities, without overlooking or omitting critical information.

This study aimed to evaluate whether the type and degree of physical activity commitment (i.e., team sport athletes, highly active individuals, sedentary behavior) influence body image and exercise behavior. A total of 96 participants (46 women and 50 men; age: 22.7 ± 2.7 years; height: 170 ± 8.6 cm; weight: 67.6 ± 10.8 kg) were divided in six groups: female volleyball and male football players (student athletes classified as Tier 2), highly physically active women and men, with high sitting time completed the Body Image Dimensional Assessment and the 21-item Exercise Dependence Scale to evaluate body dissatisfaction and level of dependency on exercise. The Body Image Dimensional Assessment is a silhouette-based scale, where three direct indices are derived from the participants' responses: body dissatisfaction, sexual body dissatisfaction, and comparative body dissatisfaction. The Exercise Dependence Scale is a six-point Likert scale that evaluates seven dimensions of exercise dependence (tolerance, withdrawal, intention effects, lack of control, time, reductions in other activities, and continuance) and provides an overall score. A multivariate analysis of variance was used to examine the effects of different levels of physical activity, team sport participation (volleyball and football), and sedentary behavior (i.e., high sitting time) on participants' body image indices and dimensions of exercise dependence according to sex. Volleyball players showed significantly higher body dissatisfaction than football players (d = 0.99) and the physically active men group (d = 2.31), who had lower values than sedentary women group (d = 1.68). Football players had lower comparative body dissatisfaction values than volleyball players (d = 1.70) and sedentary women (d = 1.69), who had higher values than sedentary men (d = 1.04). Sedentary women had a significantly lower exercise dependence scale score than volleyball players (d = 1.71), football players (d = 1.12), and physically active men (d = 1.21). The findings highlight the impact of regular physical activity on body dissatisfaction and the variance in body image perceptions between the sexes. Moreover, the high exercise dependence values found in volleyball and football players and physically active men suggest an effect of intense training and maladaptive exercise behaviors, underlining the need for comprehensive strategies to address exercise dependence.

Background: Basketball players rely on their lower limb strength for speed and agility. Therefore, it is important for strength and conditioning coaches to seek methods to assess and develop lower limb strength.

Objectives: This study aimed to identify tests and variables used to assess lower body strength among elite basketball players and to provide normative values for the commonly used strength tests.

Methods: A review of PubMed, MEDLINE, Scopus, and SPORTDiscus was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. The risk of bias was assessed using the Joanna Briggs Institute cross-sectional and cohort checklists.

Results: Among the twelve reviewed studies, seven strength tests and five outcome variables were used. The most frequently used lower limb strength tests were the back squat (nine studies) and isometric mid-thigh pull (IMTP) (three studies), both reporting one repetition maximum (1RM) and peak force metrics. The most frequently used lower limb strength test was the back squat among males and IMTP among females.

Conclusions: Among elite basketball players, the back squat 1RM is the most used lower limb strength test. However, across studies, a large variability was evidenced, which suggests that lower limb testing procedures are heterogeneous in this population.

Aging is associated with decreased muscle strength and power. Power is particularly important for maintaining the independence of older adults when performing activities of daily living. The countermovement jump has been identified as a reliable and safe method to assess lower extremity power across the lifespan. The purpose of this investigation was to study sex differences and age-related changes in countermovement jump peak power among masters weightlifters with the secondary purpose of comparing results to previous reports of community and masters athletes. Female (n = 63, 39 to 70 yrs, med (56 yrs)) and male (n = 39, 35 to 86 yrs, med (59 yrs)) participants of the 2022 World Masters Championships completed three maximal effort countermovement jump repetitions following a dynamic warm-up. Vertical ground reaction forces were recorded, and peak power normalized to body mass was calculated. Results indicated significant age-related peak power among weightlifters, with the decline being significantly more pronounced in males than females. Female weightlifters exhibited less age-related decline compared to normative data as well as the other Master athlete comparison cohorts (short and long-distance runners), whereas the males demonstrated similar age-related declines as the comparison cohorts. While the female weightlifters in the current study generally demonstrated the least age-related declines in CMJ peak power of the comparative literature, the male weightlifters showed similar age-related decline rates.

Multidisciplinary sports like triathlons require combining training for three different sports, and it is unclear how triathlon coaches manage this. During a 10-week period, we provided four age-group triathlon coaches with summary reports of the training completed by their athletes (n = 10) in the previous week. Coaches were then asked if the information provided to them was used to inform training prescription for the following week. The information provided to coaches included relative acute training load (rATL) and training stress scores (TSSs). Weekly fluctuations in rATL of >10% (spikes) were 83% (swim), 74% (bike) and 87% (run). Coaches adapted training loads for the upcoming week in 25% of all rATLs reported, and only 5% (swim), 33% (bike) and 9% (run) of the adjusted loads avoided spikes. Consequently, there were 22 single-discipline acute training load spikes vs. 14 spikes when combining all three disciplines. Only 1.5% of training was lost to injury, mostly after a large running-based training load spike (>30%). Coaches largely overlooked the information provided in the report when prescribing exercise for the following week, and when adjusted, it failed to bring weekly load variability <10%.