Elite Male Volleyball Players Are at Risk of Insufficient Energy and Carbohydrate Intake

A Decrease in Branched-Chain Amino Acids after a Competitive Male Professional Volleyball Game-A Metabolomic-Based Approach

A competitive volleyball game is a highly metabolic and physically demanding event for professional players. This study aimed to investigate whether a single game at the end of a preseason promotes changes in the biochemical markers of physical exercise responses and the metabolomic profile of professional volleyball players. This cross-sectional study included 13 male Brazilian professional volleyball players. Food intake, body composition, heart rate, physical movement variables, and blood biochemical indicators were evaluated. For non-target metabolomic analysis, serum samples were subjected to 500 MHz Nuclear Magnetic Resonance. Data analysis showed no significant difference in the biochemical indicators after the game (p > 0.05). The level of metabolites present in the groups of the main components (β-hydroxybutyrate, arginine/lysine, isoleucine, leucine, and valine) had decreased after the game. However, formic acid and histidine levels increased. Among the compounds not part of the main components, hypoxanthine and tyrosine increased, whereas low-density lipoprotein and very low-density lipoprotein levels decreased. After the game, the metabolomic profiles of players showed significant negative variations in essential amino acids (leucine, valine, and isoleucine). These decreases might be influenced by athlete diet and reduced glycogen storage due to lower carbohydrate intake, potentially impacting serum-essential amino acid levels via oxidation in skeletal muscle. The study provides insights for developing metabolic compensation strategies in athletes.

Body fat of competitive volleyball players: a systematic review with meta-analysis

BACKGROUND

Reference values of body fat for competitive volleyball players are lacking, making it difficult to interpret measurement results. This review systematically summarized published data on the relative body fat of volleyball players and calculated potential differences between sex, measurement method, and competitive level.

METHODS

The protocol followed the Preferred Reported Items for Systematic Reviews and Meta-Analysis guidelines. The literature search was conducted using five electronic databases to retrieve all relevant publications from January 1, 2010, to July 1, 2021. The 63 studies including 2607 players that met the inclusion criteria were analyzed using random-effects models. Data were reported as pooled mean body fat with 95% confidence intervals.

RESULTS

Body fat for males and females was 12.8% (11.9-13.8%) and 22.8% (21.9-23.7%), respectively. Body fat was 18.3% (16.3-20.4%) measured via skinfolds, 18.4% (15.6-21.2%) via bioelectrical impedance analysis, 24.2% (20.4-28.0%) via dual-energy x-ray absorptiometry and 21.6% (17.4-25.8%) via densitometry. Regional, national, and international-level players had body fat values of 19.5% (17.8-21.2%), 20.3% (18.6-22.0%), and 17.9% (15.7-20.4%), respectively. When the meta-regression was adjusted for the variables sex, measurement method, and competitive level, a significant difference between sex (p < 0.001), dual-energy x-ray absorptiometry and skinfolds (p = 0.02), and national and international-level players (p = 0.02) was found. However, sensitivity analysis revealed that findings regarding measurement method and competitive level were not robust and should, therefore, be interpreted with caution.

CONCLUSIONS

Despite the limitations of published data, this meta-analysis provided pooled values for body fat of male and female volleyball players for different competitive levels and measurement methods.

Signs of low energy availability in elite male volleyball athletes but no association with risk of bone stress injury and patellar tendinopathy

Relative Energy Deficiency in Sport (RED-S) syndrome is associated with undesirable health and performance outcomes. The aetiology of RED-S syndrome is low energy availability (LEA). LEA has been reported in male athletes in various sports, but there is little information in team sports. Therefore, the aims of this study were to assess the point-prevalence of surrogate markers of LEA in elite male volleyball players and examine the association between low and normal total-testosterone (TES) on endocrine markers, resting metabolic rate, bone mineral density (BMD), and history of injury/illness. Using a cross-sectional design, 22 elite male volleyball players underwent anthropometric, dual-energy X-ray absorptiometry (DEXA or DXA) and resting metabolic rate testing, bloodwork, dietary analysis, the three-factor eating questionnaire-R18, injury/illness questionnaire and Victorian Institute of Sport Assessment - patellar tendon questionnaire. The primary finding of this investigation was that 36% of athletes had ≥2 surrogate markers of LEA. Although fasted insulin was lower and cortisol was higher in players with low-total TES, low BMD, low RMR and various other endocrine markers linked to LEA were not observed. More research is required to define surrogate markers of LEA in male athletes.HIGHLIGHTS Thirty-six percent of volleyball players had ≥2 surrogate markers of LEA.The Cunningham, 1991 predictive RMR equation and/or the cut-off point (<0.9) may be unsuitable for detecting energy conservation associated with LEA in large male athletes.There was no association between total-TES and risk of bone stress injury, illness and patellar tendinopathy.

Dietary Intake of Protein and Essential Amino Acids for Sustainable Muscle Development in Elite Male Athletes

Athletes need to develop a relatively high muscle mass and low body adipose tissue for the sake of better athletic performance. A full range of nine essential amino acids and eleven non-essential amino acids have to attend in appropriate amounts for protein biosynthesis. The aim of the observational comparative cross-sectional study was to assess the association between the diet quality profile and training-induced muscle mass estimated by bioelectrical impedance among elite male athletes. The research sample comprised 18.1 ± 3.1 year-old Lithuanian professional male athletes (n = 234). The study participants were enrolled to complete 24-h dietary recalls of three non-consecutive days. The body composition was assessed using the bioelectrical impedance analysis (BIA) method. The present study showed a significant insufficiency of the mean carbohydrate intake of 5.7 g/kg/day in a group of aerobic male athletes. The lower muscle mass of aerobic male athletes was related to the lower-carbohydrate diet (adjusted odd ratio (ORadj) 0.3; 95% confidence interval (CI): 0.1-0.7). The mean protein intake of 1.8 g/kg/day was optimal for anabolism in the samples of both anaerobic and aerobic male athletes. The protein intake in appropriate doses was potentially associated with an increase in muscle mass only in anaerobic male athletes (ORadj 2.2; 95% CI: 1.3-3.7). The positive relationship was revealed between the possible muscle mass gain and the increased intakes of amino acids such as isoleucine and histidine among anaerobic athletes (ORadj 2.9; 95% CI: 1.1-4.7 and ORadj 2.9; 95% CI: 1.0-4.3, respectively). An inverse feasible association was indicated between a higher intake of valine and lower muscle mass quantities among anaerobic male athletes (ORadj 0.1; 95% CI: 0.1-0.5). The recommendations for sports nutritionists should emphasize the necessity of advising professional athletes on dietary strategies on how to manipulate dietary amino acid composition with respect to achieving long-term body composition goals.

Intersection of mental health issues and Relative Energy Deficiency in Sport (REDs): a narrative review by a subgroup of the IOC consensus on REDs

Overall athlete health is a stated priority by the International Olympic Committee (IOC), yet it can be difficult for athletes to safely balance nutritional needs, training load, recovery, social interactions, expectations and other demands. The effect of energy intake and, especially, low energy availability (LEA) on athlete mental health, is understudied. In this narrative review, we examine research that has included psychological factors and mental health variables when investigating the effect of LEA, dieting/restrictive eating and Relative Energy Deficiency in Sport (REDs), since the 2018 IOC consensus statement on REDs. Based on currently available data, early psychological indicators associated with problematic LEA are mood changes, fatigue and psychological conflict. More severe mental health outcomes associated with REDs are reduced well-being, elevated anxiety, depressive symptoms and eating disorders. We propose a psychological model that helps structure how possible risk factors (eg, body dissatisfaction, environmental demands or increased training load) and moderating (eg, gender, sport) and/or potential mediating (eg, social climate, self-esteem) factors are associated with LEA and ultimately REDs. The current scientific literature underscores the importance of including mental health factors when screening for REDs and for developing a clinical approach to address the psychological sequelae of REDs once diagnosed. An interdisciplinary perspective is recommended. Lastly, and importantly, the athlete perspective urges clinicians to not underestimate the drive for success and denial of health consequences that athletes demonstrate when pursuing their sport goals.

Energy and Macronutrients Intake in Indoor Sport Team Athletes: Systematic Review

Indoor team sports are characterized by matches that are shorter in duration and with frequent substitution (high-intensity intermittent). The main goal of teams is to best cover athletes' physiological demands, while meeting their dietary intake needs is critical. The aim of this study is to conduct a systematic review of the dietary intake of indoor team sports athletes and to analyze whether they comply with nutritional recommendations. A search of PubMed-MEDLINE, Web of Science, and Scopus databases from 2008 to July 2022 was conducted and 2727 documents were identified. The studies focused on adult professional or semi-professional volleyball, basketball, handball, or futsal athletes. Two independent researchers screened and extracted the data, with 20 documents included after they met the inclusion criteria. Most of the athletes, both men and women, did not meet the official recommendations based on under-consumption (energy and carbohydrates) or over-consumption (fats). In relation to protein, 28.6% of studies met the recommendations, with 50% of those who did not meet it being due to under-consumption. Although there are references on athletes' dietary intakes, there are no references considering sexes or types of sport. More adapted recommendations are needed in order to more precisely evaluate athletes' intake to know if they meet their real nutritional requirements.