UEFA expert group statement on nutrition in elite football. Current evidence to inform practical recommendations and guide future research

Effects of different dietary supplements on athletic performance in soccer players: a systematic review and network meta-analysis

BACKGROUND

As dietary supplements play a crucial role in meeting the unique nutritional needs of soccer players, a growing body of studies are exploring the effects of dietary supplements on athletic performance in soccer players. The effectiveness of certain supplements, such as caffeine and creatine, remains debated due to inconsistent results across studies. Therefore, this systematic review and Bayesian network meta-analysis was conducted to tentatively identify the most effective dietary supplements for soccer players.

METHODS

We searched PubMed, Web of Science, Cochrane, Embase, and SPORTDiscus from database establishment to 5 February 2024 to identify randomized controlled trials (RCTs) evaluating the effects of different dietary supplements on athletic performance in soccer players. The risk of bias was assessed using the revised Cochrane risk-of-bias tool for randomized trials. A Bayesian network meta-analysis was performed using the R software and Stata 18.0. A subgroup analysis was conducted based on the competitive level of the athletes.

RESULTS

Eighty RCTs were included, with 1,425 soccer players randomly receiving 31 different dietary supplements or placebo. The network meta-analysis showed that compared with placebo, carbohydrate + protein (SMD: 2.2, very large), carbohydrate + electrolyte (SMD: 1.3, large), bovine colostrum (SMD: moderate) and caffeine (SMD: 0.29, small) were associated with a significant effect on increasing the distance covered. Kaempferia parviflora (SMD: 0.46, small) was associated with a significant effect on enhancing muscular strength. Beta-alanine (SMD: 0.83, moderate), melatonin (SMD: 0.75, moderate), caffeine (SMD: 0.37, small), and creatine (SMD: 0.33, small) were associated with a significant effect on enhancing jump height. Magnesium creatine chelate (SMD: -3.0, very large), melatonin (SMD: -1.9, large), creatine + sodium bicarbonate (SMD: -1.4, large), and arginine (SMD: -1.2, moderate) were associated with a significant effect on decreasing sprint time. Creatine + sodium bicarbonate (SMD: -2.3, very large) and caffeine (SMD: -0.38, small) were associated with a significant effect on improving agility. Sodium pyruvate (SMD: 0.50, small) was associated with a significant effect on increasing peak power. Magnesium creatine chelate (SMD: 1.3, large) and sodium pyruvate (SMD: 0.56, small) were associated with a significant effect on increasing mean power. Carbohydrate + electrolyte (SMD: -0.56, small) was associated with a significant effect on improving the rating of perceived exertion.

CONCLUSIONS

This study suggests that a range of dietary supplements, including caffeine, creatine, creatine + sodium bicarbonate, magnesium creatine chelate, carbohydrate + electrolyte, carbohydrate + protein, arginine, beta-alanine, bovine colostrum, Kaempferia parviflora, melatonin, and sodium pyruvate, can improve athletic performance in soccer players. This review provides evidence-based guidance for soccer coaches and nutritionists on using dietary supplements to enhance specific performance measures.

Fueling Soccer Players: A Scoping Review and Audit of Literature Related to Soccer-Specific Guidelines for Carbohydrate Intake

BACKGROUND

Professional soccer players are advised to consume 3-8 g kg-1 body mass day-1 of carbohydrate (CHO) on the basis of training demands, fixture schedule and personal objectives. However, owing to the lack of randomized controlled trials on elite players, these guidelines largely rely on data interpretation and practitioner experience.

OBJECTIVE

To identify the gaps in existing literature that inform CHO guidelines for soccer players.

METHODS

A scoping review was conducted without date restrictions up to 21 March 2024, employing a three-step search strategy to identify relevant English-language primary and secondary articles through PubMed and reference searching. Data were extracted using a standardized audit tool from studies assessing direct and indirect impacts of CHO on soccer players' performance and health.

RESULTS

Within 258 studies identified, experimental studies were the most common (~ 36%), followed by observational (~ 33%) and narrative reviews (~ 26%), with systematic reviews, meta-analyses and case studies making up the rest (~ 5%). Most observational studies were field-based (~ 98%), while experimental studies were laboratory-based (~ 75%). Among 4475 participants, ~ 16% were female, and only ~ 12% of the original research was exclusively conducted on female players. Observational studies included developmental (~ 52%) and professional players (~ 31%), whereas experimental studies primarily featured recreationally active (~ 40%) and collegiate/university participants (~ 26%). Key research topics were 'dietary intake' (~ 52%) and "energy expenditure and dietary intake" (~ 30%) for observational studies and 'CHO interventions' (~ 74%) for experimental studies. Only eight experimental studies exclusively involved professional players, focusing on CHO intervention (n = 7) and CHO co-ingestion (n = 1). Narrative reviews were published in journals with higher impact factor (4.1 ± 6.4) than were observational studies (3.2 ± 1.6, p < 0.001) and experimental studies (3.4 ± 1.6, p < 0.001). Narrative reviews had the most studies, with Altmetric scores ≥ 20 (n = 26), followed by experimental (n = 16) and observational studies (n = 14).

CONCLUSIONS

Current CHO guidelines for elite soccer players lack experimental research specific to professional and world-class players. More field-based experimental trials involving elite soccer players are required to ensure evidence-based CHO recommendations.

Accuracy of anthropometric-based predictive equations for tracking fat mass over a competitive season in elite female soccer players: a validation study

BACKGROUND AND AIMS

Body fat is a key body composition parameter monitored in soccer. Identifying reliable alternatives to laboratory techniques for assessing body fat during the competitive period is essential. This study aimed to evaluate the cross-sectional and longitudinal validity of anthropometric prediction equations in elite female soccer players.

METHODS

Eighteen female soccer players (age: 26.6 [3.8] years; height: 168 [6.3] cm; body mass: 64.1 [7.4] kg; body mass index: 22.7 [1.9] kg/m²) from an Italian Serie A team were assessed at four time points during a competitive season. Fat mass was estimated using anthropometric equations by Evans and Warner and compared to dual-energy X-ray absorptiometry (DXA), which served as the reference method.

RESULTS

Cross-sectional agreement analysis revealed a bias of -4.5% with Warner's equation, while Evans's equation showed no bias compared to DXA, with coefficient of determination (R²) values of 0.69 and 0.70, respectively. Both methods showed a negative association (Evans: r = -0.53, Warner: r = -0.63) when the difference between the values and the mean with DXA were correlated. Longitudinal agreement analysis showed no significant differences in fat mass changes between the anthropometric equations and DXA, with R² values ranging from 0.68 to 0.83. The 95% limits of agreement between the methods for individual changes in fat mass ranged from - 3.3 to 3.2%. Furthermore, no significant changes (p > 0.05) in fat mass were observed over the season with any method.

CONCLUSIONS

At the group level, Evans's equation provides valid estimates of fat mass, whereas it may overestimate values in players with low body fat and underestimate them in those with high fat mass. The Warner equation showed the same trend as Evans at the individual level, also resulting in poor accuracy at the group level. Despite this, both anthropometric equations are valid alternatives to DXA for monitoring fat mass changes during the season, with Evans's equation showing superior overall performance.

Professional Male Soccer Players' Perspectives of the Nutrition Culture Within an English Premier League Football Club: A Qualitative Exploration Using Bourdieu's Concepts of Habitus, Capital and Field

BACKGROUND AND AIM

Professional soccer players' self-reported dietary intakes often do not meet recommended sport nutrition guidelines. Although behaviour change models have previously explored barriers and enablers to nutritional adherence, the cultural factors influencing players' nutritional habits also warrant investigation. Accordingly, we aimed to explore players' perceptions of the nutrition culture within the professional soccer environment.

METHODS

An interpretivist paradigm, which emphasises that reality is subjectively and socially constructed, underpins this study. Qualitative, face-to-face semi-structured interviews (comprising open-ended questions) were conducted with purposively sampled male soccer players from the English Premier League (EPL) (five British, five migrant; mean age: 26 ± 6 years; mean EPL appearances: 106 ± 129). Data were abductively analysed using thematic analysis according to Bourdieu's concepts of habitus, capital, field and doxa practices.

RESULTS

This study revealed five key themes: (1) players' habitus, as shaped by familial, ethnic and religious backgrounds, influences their dietary habits; (2) social capital, via managers (head coaches), teammates and online influences, impact players' dietary practices; (3) the increase in both soccer clubs' and players' economic capitals has advanced nutrition provision; (4) an unequal distribution of economic capitals has led to hierarchical practice in the performance nutrition field with personalised nutrition being somewhat enacted at the higher levels; and (5) body composition measurement is a 'doxic' practice in professional soccer that warrants challenge.

CONCLUSIONS

Soccer players' habitual nutritional practices are influenced by personal upbringing and the club context, including economic resources and social capital from managers. The performance nutrition field within professional soccer is also shaped by stakeholders' doxic beliefs surrounding the perceived optimal body composition of players, with managers exerting social capital.

No Effect of Delaying a Carbohydrate-Rich Breakfast on Afternoon High-Intensity Intermittent Exercise Performance in Trained Games Players: A Randomized, Single-Blind, Placebo-Controlled Trial

This study tested the hypothesis that delaying consumption of a carbohydrate-rich breakfast by 2 hr would impair prolonged high-intensity intermittent exercise performance in the afternoon. Fifteen intermittent games players (mean ± SD: age: 24 ± 6 years; V˙O2peak: 46 ± 6 ml·kg-1·min-1) completed a randomized, single-blind, placebo-controlled crossover study with two trials (EARLY and DELAY) matched for dietary intake. In EARLY, participants consumed a high-carbohydrate (semisolid) breakfast shake (2 g/kg BM maltodextrin, 1 ml/kg BM orange squash, 0.15 g/kg BM xanthan gum, 0.067 g/kg BM artificial sweetener, and 6 ml/kg BM water) at 8 a.m., followed by a taste and texture matched, but energy depleted, placebo shake 2 hr later. In DELAY, the order of these shakes was reversed. Three hours following a high-carbohydrate lunch (888 ± 107 Kcal, 145 ± 28 g carbohydrate), participants completed a 90-min intermittent cycling test, consisting of two 40-min halves, with 10 min of rest in between. Each half involved 18 repeated 2-min blocks of steady-state cycling (100 s; 35% Wmax), followed by 15 s of unloaded pedaling and a 6-s all-out sprint. There were no differences in peak power (first half: mean difference [95% confidence interval]: 6.6 [-10.9, 24.1] W, d = 0.03 and second half: 8.5 [-6.5, 23.6] W, d = 0.04) or mean power (first half: mean difference: 6.4 [-10.7, 23.5] W, d = 0.03 and second half: mean difference: 7.3 [-6.5, 21.3] W, d = 0.04) during the sprints between the DELAY and EARLY conditions. In contrast with our hypothesis, these data provide no evidence that delaying consumption of a carbohydrate-rich breakfast by 2 hr impairs prolonged high-intensity intermittent exercise performance in the afternoon.

Nutritional Strategies for Optimizing Health, Sports Performance, and Recovery for Female Athletes and Other Physically Active Women: A Systematic Review

CONTEXT

Despite the progress toward gender equality in events like the Olympic Games and other institutionalized competitions, and the rising number of women engaging in physical exercise programs, scientific studies focused on establishing specific nutritional recommendations for female athletes and other physically active women are scarce.

OBJECTIVE

This systematic review aimed to compile the scientific evidence available for addressing the question "What dietary strategies, including dietary and supplementation approaches, can improve sports performance, recovery, and health status in female athletes and other physically active women?"

DATA SOURCES

The Pubmed, Web of Science, and Scopus databases were searched.

DATA EXTRACTION

The review process involved a comprehensive search strategy using keywords connected by Boolean connectors. Data extracted from the selected studies included information on the number of participants and their characteristics related to sport practice, age, and menstrual function.

DATA ANALYSIS

A total of 71 studies were included in this review: 17 focused on the analysis of dietary manipulation, and 54 focused on the effects of dietary supplementation. The total sample size was 1654 participants (32.5% categorized as competitive athletes, 30.7% as highly/moderately trained, and 37.2% as physically active/recreational athletes). The risk of bias was considered moderate, mainly for reasons such as a lack of access to the study protocol, insufficient description of how the hormonal phase during the menstrual cycle was controlled for, inadequate dietary control during the intervention, or a lack of blinding of the researchers.

CONCLUSION

Diets with high carbohydrate (CHO) content enhance performance in activities that induce muscle glycogen depletion. In addition, pre-exercise meals with a high glycemic index or rich in CHOs increase CHO metabolism. Ingestion of 5-6 protein meals interspersed throughout the day, with each intake exceeding 25 g of protein favors anabolism of muscle proteins. Dietary supplements taken to enhance performance, such as caffeine, nitric oxide precursors, β-alanine, and certain sport foods supplements (such as CHOs, proteins, or their combination, and micronutrients in cases of nutritional deficiencies), may positively influence sports performance and/or the health status of female athletes and other physically active women.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD480674.

Dietary Supplement Use in Competitive Spanish Football Players and Differences According to Sex

Objectives: This study aimed to evaluate and compare the consumption of dietary supplements (DS) in semi-professional male and professional female Spanish football players. Methods: The study involved 129 football players (92 men and 37 women) who completed a validated, self-administered questionnaire on the use of DS in athletes. Results: The results indicated that 96.12% of the sample reported taking DS, with the main reason for consumption being performance enhancement. The most commonly consumed DS were creatine monohydrate (66.77%), caffeine (56.59%), whey protein (48.06%), isotonic drinks (37.21%), vitamin D (27.91%), energy bars (27.13%), magnesium (20.93%), and vitamin C (20.16%). Additionally, significant differences were found between sexes regarding vitamin D consumption (p < 0.05; OR = 3.27 [0.36-2.00]). According to the Australian Institute of Sport DS classification, group A was the most consumed, followed by group B. Significant sex differences were found in the consumption of sports foods (p = 0.034; OR = 3.25 [0.05-2.31]) and medical supplements (p < 0.001; OR = 3.75 [0.52-2.12]). Sex differences were also found in place of purchase, source of recommendation, as well as the situation and timing of consumption (p < 0.05). Conclusions: The use of DS among Spanish football players was prevalent at 96.12%, with creatine monohydrate, caffeine, and whey protein being the most commonly consumed. Differences in consumption patterns were noted between sexes.

The race within a race: Together on the marathon starting line but miles apart in the experience

Every four years the world's best athletes come together to compete in the Olympic games, electrifying audiences with incredible feats of speed, strength, endurance and skill as personal best performances and new records are set. However, the exceptional talent that underpin such performances is incomprehensible to most casual observers who often cannot appreciate how unique these athletes are. In this regard, endurance running, specifically the marathon, a 42.195 km foot race, provides one of the few occasions in sport outside of Olympic, world and national competitions, that permits sport scientists and fans alike to directly compare differences in the physiology between recreational and elite competitors. While these individuals may all cover the same distance, on the same course, on the same day - their experience and the physiological and psychological demands placed upon them are vastly different. There is, in effect, a "race within a race". In the current review we highlight the superior physiology of the elite endurance athlete, emphasizing the gap between elite competitors and well-trained, but less genetically endowed athletes. We draw attention to a range of inconsistencies in how current sports science practices are understood, implemented, and communicated in terms of the elite and not-so-elite endurance athlete.

Assessing Nutritional Knowledge and Physical Health Among Football Players: A Pilot Study from Three Sports Clubs in Western Romania

BACKGROUND

Football players require optimal nutrition and physical fitness to enhance their performance and maintain their health. Understanding the relationships among nutritional knowledge, dietary habits, physical health, and substance use in athletes is essential for developing effective strategies. This study investigates these factors in male football players aged 16-33 years.

METHODS

The study involved 60 male football players from three teams in Liga4Arad. A mixed-methods approach was used, incorporating a self-developed pilot questionnaire and internationally validated instruments. The reliability of the questionnaire was confirmed using Guttman's λ2. The questionnaire assessed nutritional knowledge, eating habits, substance use, and physical health parameters, including body fat percentage and training frequency. Spearman's correlation was used to analyze the data and explore the interrelationships between these factors. It is important to note that the pilot questionnaire used in this study was self-developed and not previously validated in this specific context.

RESULTS

Nutritional knowledge was positively correlated with healthier eating habits (ρ = 0.675, p < 0.001). Intensive training and higher physical activity levels were both associated with improved body composition and lower body fat (ρ = 0.341, p = 0.006). Supplement use was moderately correlated with alcohol consumption (ρ = 0.548, p < 0.001) and weakly correlated with smoking (ρ = 0.348, p = 0.007).

CONCLUSIONS

The study highlights a strong relationship between nutritional knowledge and healthier eating habits among football players, as well as the significant role of frequent intense training in reducing body fat percentages and enhancing physical fitness. Additionally, the findings suggest a moderate association between dietary supplement use and alcohol consumption, underscoring the need for tailored interventions to address substance use and its impact on players' health behaviors and performance.

Training with reduced carbohydrate availability affects markers of bone resorption and formation in male academy soccer players from the English Premier League

PURPOSE

To test the hypothesis that training with reduced carbohydrate (CHO) availability increases bone resorption in adolescent soccer players.

METHODS

In a randomised crossover design, ten male players (age: 17.4 ± 0.8 years) from an English Premier League academy completed an acute 90-min field-based training session (occurring between 10:30-12:00) in conditions of high (TRAIN HIGH; 1.5 g.kg-1, 60 g, 1.5 g.kg-1 and 1.5 g.kg-1 consumed at 08:00, during training, 12:30 and 13:30, respectively) or low CHO availability (TRAIN LOW; 0 g.kg-1). Participants also completed a non-exercise trial (REST) under identical dietary conditions to TRAIN LOW. Venous blood samples were obtained at 08:30, 10:30, 12:30 and 14:30 for assessment of bone resorption (βCTX), bone formation (PINP) and calcium metabolism (PTH and ACa).

RESULTS

External training load did not differ (all P > 0.05) between TRAIN HIGH and TRAIN LOW, as evident for total distance (5.6 ± 0.8; 5.5 ± 0.1 km), average speed (81 ± 9; 85 ± 12 m.min-1) and high-speed running (350 ± 239; 270 ± 89 m). Area under the curve for both βCTX and PINP was significantly greater (P < 0.01 and P = 0.03) in TRAIN LOW versus TRAIN HIGH, whilst no differences in PTH or ACa (P = 0.11 and P = 0.89) were observed between all three trials.

CONCLUSION

CHO restriction before, during and after an acute soccer training session increased bone (re)modelling markers in academy players. Despite acute anabolic effects of bone formation, the long-term consequence of bone resorption may impair skeletal development and increase injury risk during growth and maturation.

Nutritional perspectives in female soccer: a scoping review

BACKGROUND

The purpose of the review was to evaluate the literature exploring nutritional habits and practices in female soccer players.

METHODS

The PRISMA-ScR Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews were followed. Searches of Web of Science, PubMed and Scopus databases were conducted for studies exploring the nutritional habits and practices of female soccer players.

RESULTS

A total of 72 studies were included in the scoping review. Studies on female soccer players mainly focused on daily energy expenditure, daily energy and macronutrient intake and hydration status. A negative energy balance was consistent across studies, and the ingestion of CHO appears below the current recommendations. Female soccer players are predominately in negative energy balance, which may indicate that they are at risk of low energy availability. A high use of nutritional supplements is apparent in female soccer, whilst a large proportion of players commence training dehydrated.

CONCLUSIONS

The current findings have implications for practitioners relating to the planning, management, monitoring, and implementation of nutritional intake and training and competition schedules.

Contemporary educational and behavior change strategies improve dietary practices around a match in professional soccer players

BACKGROUND

The importance of nutrition in optimizing the health and performance of professional soccer players has been well established. Despite published practical recommendations for the dietary requirements for professional soccer players, many players fail to meet these guidelines. Thus, the primary purpose of this study was to assess the impact of targeted nutritional education and behavior change interventions on dietary intake in professional football players. Additionally, previous research within this population has reported elevations in resting metabolic rate (RMR) following match-play. Therefore, a further aim of this study was to examine whether any changes in dietary intake would influence RMR following match-play.

METHODS

Twenty players from the professional development phase in an English Premier League club (age: 18.4 ± 1.0 years; body mass: 76.1 ± 6.0 kg; stature: 1.80 ± 0.07 m) were randomly assigned to an "Intervention" (INT) group (n = 10), who received numerous nutritional education and behavior change interventions, or a "Control" (CON) group (n = 10), who received no nutrition support. Dietary intake was assessed daily throughout the match-week (Match Day (MD)-2, MD-1, MD, MD + 1, and MD + 2), whilst RMR was assessed on MD-1, MD + 1, and MD + 2. Statistical analyses on the intervention effects on dietary intake and RMR were carried out using a two factor (group and day) analysis of variance (ANOVA) with a subsequent Bonferroni post-hoc test.

RESULTS

Mean energy (3393 ± 852 vs. 2572 ± 577 kcal · day-1) and CHO (5.36 ± 1.9 vs. 3.47 ± 1.1 g · kg-1 BW · day-1) intake was significantly higher (p < 0.001) in the INT vs. CON group. Furthermore, the INT group implemented nutrition periodization practices as CHO intake was significantly increased on MD-1 (7.0 ± 1.7 g · kg-1 BM · day-1), MD (7.1 ± 1.4 g · kg-1 BM · day-1) and MD + 1 (5.1 ± 0.8 g · kg-1 BM · day-1). However, the CON group did not periodize their CHO intake and failed to meet the CHO recommendations on MD-1, MD, and MD + 1 (<4 g · kg-1 BM · day-1). Compared to MD-1, the RMR increased on MD + 1 and MD + 2 in both groups, although it was only statistically significant for the INT group (MD + 1 =  +243 kcal · day-1; MD + 2 =  +179 kcal · day-1).

CONCLUSIONS

The implementation of targeted nutritional education and behavior change interventions resulted in improved dietary practices in professional football players and enabled better adherence to recommended guidelines. However, despite this, RMR was still elevated in the 24-48 h following match play. Thus, in order to optimize recovery, this finding further reinforces the need for professional football players to adopt strategies to meet energy, and particularly CHO, requirements in the acute period following a match in order to account for this increase in energy requirement.

Testing in Football: A Narrative Review

Football clubs regularly test and monitor players, with different approaches reflecting player age and competitive level. This narrative review aims to summarise justifications for testing and commonly used testing protocols. We also aim to discuss the validity and reliability of specific tests used to assess football players and provide a holistic overview of protocols currently used in football or those demonstrating potential utility. The PubMed, SportDiscus, and Google Scholar databases were screened for relevant articles from inception to September 2024. Articles that met our inclusion criteria documented tests for several purposes, including talent identification or the assessment of growth/maturation, physiological capacity, sport-specific skill, health status, monitoring fatigue/recovery, training adaptation, and injury risk factors. We provide information on specific tests of anthropometry, physical capacity, biochemical markers, psychological indices, injury risk screening, sport-specific skills, and genetic profile and highlight where certain tests may require further evidence to support their use. The available evidence suggests that test selection and implementation are influenced by financial resources, coach perceptions, and playing schedules. The ability to conduct field-based testing at low cost and to test multiple players simultaneously appear to be key drivers of test development and implementation among practitioners working in elite football environments.

Enhancing match official performance: a forward-thinking approach for football evolution

The future of football demands more from players and referees due to heightened match intensity and frequency. To optimize performance and health, collaboration among sport scientists, coaches, and medical staff is crucial. However, match officials often lack the same support as elite players, hindering their development. Granting professional status to referees, implementing evidence-based training, and adopting gender-inclusive methods are vital. Coping with future challenges requires better career support and economic conditions for officials, along with research to enhance their performance and health.

Skinfold thickness in elite male professional football players: changes across 3 seasons including a COVID-19 lockdown period

This study investigates variations in skinfold thickness in a European professional football team within and across multiple seasons, including before and after COVID-19 restrictions. Skinfold thickness was measured in 49 male players on 32 occasions across three seasons (2018/19, 2019/20 and 2020/21). Intra- and inter-seasonal trends were examined by comparing values for the sum of eight skinfolds (sum8) at key time points using linear mixed models. In each season, the largest differences in sum8 occurred after the preseason period. These differences ranged from a mean difference (Mdiff) of -11.0 mm (p < 0.001) in 2018/19 to -4.8 mm (p < 0.001) in 2020/21. Increases in sum8 occurred after each off-season; however, the increase after the off-season before the 2020/21 season (which included the COVID-19 lockdown period) was the lowest in magnitude and was not statistically significant (Mdiff = 2.9 mm, p = 0.06). Changes occurring in sum8 between the start and end of the competitive season did not follow a consistent pattern and were generally smaller in magnitude than the changes between other seasonal time points. Despite the notable heterogeneity in sum8 between players, changes within players generally followed a similar pattern between the different seasonal timepoints. In summary, changes in skinfold thickness were predominantly related to off-season and 'preparation for competition' periods. Increases in skinfold thickness can be mitigated during extended remote training periods with appropriate training and nutritional strategies.

Short-Term Cocoa Supplementation Influences Microbiota Composition and Serum Markers of Lipid Metabolism in Elite Male Soccer Players

OBJECTIVES

Dietary strategies to improve arachidonic acid:eicosapentaenoic acid (AA:EPA) ratios are of interest due to potential reductions in inflammation and oxidative stress following exercise. The aim of this study was to investigate the impact of a novel dietary intervention, that is, the ingestion of 30 g of dark chocolate, on blood lipid profiles and gut microbiota composition in elite male soccer players.

METHODS

Professional male soccer players were randomly assigned to the experimental group (DC) provided with 30 g of dark chocolate or to the control group (WC), provided with 30 g of white chocolate, for 30 days. Before and after intervention, blood, fecal sample, and anthropometry data were collected. For each outcome, two-way repeated-measure analysis of variance was used to identify differences between baseline and endpoint (Week 4), considering treatment (dark chocolate, white chocolate) as intersubjects' factors. Metagenomic analysis was performed following the general guidelines, which relies on the bioBakery computational environment.

RESULTS

DC group showed increased plasma polyphenols (from 154.7 ± 18.6 μg gallic acid equivalents/ml to 185.11 ± 57.6 μg gallic acid equivalents/ml, Δ pre vs. post = +30.41 ± 21.50) and significant improvements in lipid profiles: total cholesterol (Δ -32.47 ± 17.18 mg/dl DC vs. Δ -2.84 ± 6.25 mg/dl WC, Time × Treatment interaction p < .001), triglycerides (Δ -6.32 ± 4.96 mg/dl DC vs. Δ -0.42 ± 6.47 mg/dl WC, Time × Treatment interaction p < .001), low-density lipoprotein (Δ -18.42 ± 17.13 mg/dl vs. Δ -2.05 ± 5.19 mg/dl WC, Time × Treatment interaction p < .001), AA/EPA ratio (Δ -5.26 ± 2.35; -54.1% DC vs. Δ -0.47 ± 0.73, -6.41% WC, Time × Treatment interaction p < .001) compared with WC group. In addition, 4 weeks of intervention showed a significant increase in high-density lipoprotein concentration in DC group (Δ + 3.26 ± 4.49 mg/dl DC vs. Δ -0.79 ± 5.12 mg/dl WC). Microbial communities in the DC group maintained a slightly higher microbial stability over time (exhibiting lower within-subject community dissimilarity).

CONCLUSION

Ingesting 30 g of dark chocolate over 4 weeks positively improved AA:EPA ratio and maintained gut microbial stability. Dark chocolate ingestion represents an effective nutritional strategy to improve blood lipid profiles in professional soccer players. What Are the Findings? Ingesting 30 g of dark chocolate for 4 weeks positively influences blood lipid AA: EPA ratio while maintaining gut microbial stability. What This Study Adds? Dietary intake of specific foods such as dark chocolate represents an alternative strategy to support the health and recovery of elite soccer players. What Impact Might This Have on Clinical Practice in the Future? From a clinical and translational perspective, dark chocolate ingestion positively modulates favorable blood lipid profiles and polyunsaturated fatty acid metabolism while maintaining gut microbial stability. Dark chocolate ingestion may be considered as an effective nutritional strategy in elite sport environments during periods of high-intensity training and congested competitions. Further research is required to determine functional outcomes associated with the observed improvements in blood lipid profiles.

Influence of Carbohydrate Intake on Different Parameters of Soccer Players' Performance: Systematic Review

BACKGROUND

The objective of this systematic review is to analyze the influence of carbohydrate (CHO) intake on physical and technical aspects, glucose and muscle glycogen levels, fatigue, cognition, and gastrointestinal comfort involved in the performance of soccer players, as well as to examine whether there are any differences between men and women.

METHODS

A bibliographic search was conducted in PubMed, Web of Science, Scopus, and SportDiscus, resulting in 61 selected articles. The PRISMA recommendations and the Cochrane Handbook for Systematic Reviews guidelines were followed.

RESULTS

The results indicate that CHO intake before and during the match improves speed and the number of sprints, attenuates the decrease in shooting accuracy and speed, increases time to fatigue, and enhances cognitive function. There is no consensus on passing, dribbling, jumping, or agility improvements. Glucose levels drop during the first 15 min of the second half without affecting performance.

CONCLUSIONS

It is recommended that players ingest 6-8 g/kg/d of CHO the day before, a meal with 1-3 g/kg 3-4 h before, and 30-60 g/h during the match. Muscle glycogen drops drastically at the end of the match, remaining low at 48 h. Hence, 1-1.5 g/kg/h is recommended during the first 4 h, starting from the first 20 min. Female soccer players have a similar physical demand to men, and energy availability is low, especially in the post-match periods, as they underestimate their energy expenditure and do not consume enough CHO. Therefore, the recommended guidelines should be followed, individualized, and periodized according to each athlete's energy needs.

Perceptual Health and Wellbeing, Self-Reported Sleep, and Hydration Status in Youth Soccer Players During Competition

Introduction: The aim of this study was to assess match time courses on hydration, wellness, and sleep as well as the interrelationship between these variables in youth national soccer players. Materials and Methods: Under-17 and under-19 youth national soccer players (age range: 16.96 ± 1.17 years) completed a perceptual wellness questionnaire, self-reported their sleep, and carried out hydration assessments each morning during a period of competitive match play. Results: Players reported having significantly more sleep leading into the day of a match (MD) compared to both the evening after a match (MD-2; p < 0.001; CI = 7.972 and 8.212) and the evening before a match (MD-1; p < 0.001; CI = 7.996 and 8.174). Furthermore, players reported better health and wellbeing scores on MD compared to both MD-1 (p < 0.001; CI = 19.231 and 19.692) and MD-2 (p < 0.001; CI = 18.911 and 19.489). When self-reported sleep was correlated with the individual components of health and wellbeing, it was highlighted that there were significant effects for fatigue (r = 0.304, p < 0.001; CI = 0.250 and 0.383), mood (r = 0.170, p < 0.001; CI = 0.112 and 0.243), general muscle soreness (r = 0.225, p < 0.001; CI = 0.162 and 0.306), and stress (r = 0.203, p < 0.001; CI = 0.147 and 0.274). Conclusion: It is important to consider sleep strategies to mitigate the potential impact of lack of sleep following match play. Self-reported sleep seems to be appropriate for estimating individual components of health and wellbeing, and therefore may be a suitable replacement for perceptual wellness questionnaires.

Performance variables and nutritional status analysis from Moroccan professional and adolescent football players during the competition period: a descriptive study

Introduction

Nutrition plays an integral role in optimizing football players' performance during training sessions and matches and maintaining their overall health throughout the season. This study aimed to evaluate how well the dietary practices of professional and adolescent football players in Morocco during the competitive period met international macronutrient recommendations, and to explore the relationship between their nutritional status and aerobic performance, as measured by the Yo-Yo IRL1 test.

Methods

A total of 277 footballers from Morocco's professional league, "Botola-Pro", were monitored over a seven-day (training microcycle) during the competitive period. The dietary intake was assessed through self-reported methods and 24-hour recalls. Relevant body composition was measured with bioelectrical impedance (BI), and aerobic performance was evaluated using the Yo-Yo IR test.

Results

The results indicated significant variations in performance and nutritional status across different categories and age groups. The nutritional status of the players didn't match the UEFA recommendations (p < 0.001). We found that higher intake levels of carbohydrates and proteins were positively correlated with the total distance covered by the players (p < 0.001, r = 0.63, R2 = 0.4 for carbohydrates; p < 0.001, r = 0.59, R2 = 0.35 for proteins). Conversely, a higher proportion of energy derived from fats in the diet was negatively correlated with the distance covered (p < 0.001, r = -0.64, R2 = 0.41).

Conclusion

These findings suggest that optimizing carbohydrates and protein intake while managing fat consumption is crucial for enhancing sporting performance. This information is essential for tailoring training programs and nutritional regimens based on the competition level.

'Supporting the Support Staff': A Narrative Review of Nutritional Opportunities to Enhance Recovery and Wellbeing in Multi-Disciplinary Soccer Performance Staff

BACKGROUND

With ever-increasing training, match-play and travel demands in professional soccer, recovery is vital for athletic performance, a statement amplified in tournament and in-season scenarios. However, alongside supporting the tasks associated with these increased demands, the recovery and wellbeing strategies recommended for playing staff are often unavailable to their support staff counterparts, who routinely experience extended working hours over and above scheduled player attendance.

METHODS

Focusing on the contributions of nutrition to this undoubtedly multifactorial issue, this narrative review aimed to (1) identify potential strategies to enhance recovery and wellbeing in multi-disciplinary soccer support staff and (2) highlight future research opportunities exploring the benefits of nutrition for those staff in soccer performance-related support roles.

RESULTS

The potential health and wellbeing consequences of chronic sub-optimal practices suggest that chrononutrition strategies may be an area of future interest. Notably, nutritional strategies that enhance sleep hygiene and immune function warrant consideration. Individualizing such strategies to maximize recovery and wellbeing in multi-disciplinary soccer support staff should offer an adjunct and complementary strategy to the holistic performance-focused support provided to professional soccer players.

CONCLUSIONS

Policymakers responsible for organizational and club structures aligned with soccer performance could consider 'Supporting the Support Staff' when seeking to improve overall performance.

Is Micronutrient Supplementation Helpful in Supporting the Immune System during Prolonged, High-Intensity Physical Training?

It is well known that during prolonged, high-intensity physical training, athletes experience a state of immunosuppression and that balanced nutrition can help maintain immunity. This review summarizes the effects (amplified by virus infection) of high-intensity, long-term exercise on immunity, critically presenting key micronutrients and supplementation strategies that can influence athletes' performance and their immune system. The main conclusion is that micronutrient supplementation with diet could help to protect the immune system from the stress effects induced by intense physical activities. The importance of personalized supplementation has been also recommended.

IOC consensus statement on elite youth athletes competing at the Olympic Games: essentials to a healthy, safe and sustainable paradigm

With the pronounced ongoing growth of global youth sports, opportunities for and participation of youth athletes on the world sports stage, including the Olympic Games, are expected to escalate. Yet, adolescence is a vulnerable period of development and inherently dynamic, with non-linear and asynchronous progression of physical, physiological, psychological and social attributes. These non-concurrent changes within and between individuals are accompanied by irregular and unpredictable threats and impediments. Likewise, the evident age-based criteria and conventional path for those youth athletes deemed eligible candidates for the Olympic Games are not well or consistently defined. Furthermore, the unstructured and largely varying policies and practices across the sporting International Federations specific to youth participation underscore the need to establish a contemporary universal paradigm that would enable elite youth athletes to navigate an individualised healthy pathway to personal, athletic and sport success. First, we reviewed and summarised key challenges facing elite youth athletes and the relevant evidence fundamental to facilitating and supporting central aspects of health and well-being, while empowering safe, sustainable and positive engagement during athletic and personal advancement and competition. Second, we developed and present a modern elite youth athlete model that emphasises a child-centred, practical framework with corresponding guidelines and recommendations to protect health and well-being while safely and favourably managing international sport competition. Our proposed evidence-informed paradigm will enable and support individualised pathways for healthy, well-rounded and sustainable positive engagement while achieving sport success for youth contending or aiming to compete at world-class international sporting events.

Caffeine Gum Improves Reaction Time but Reduces Composure Versus Placebo During the Extra-Time Period of Simulated Soccer Match-Play in Male Semiprofessional Players

This study aimed to determine whether caffeine gum influenced perceptual-cognitive and physical performance during the extra-time period of simulated soccer match-play. Semiprofessional male soccer players (n = 12, age: 22 ± 3 years, stature: 1.78 ± 0.06 m, mass: 75 ± 9 kg) performed 120-min soccer-specific exercise on two occasions. In a triple-blind, randomized, crossover design, players chewed caffeinated (200 mg; caffeine) or control (0 mg; placebo) gum for 5 min following 90 min of soccer-specific exercise. Perceptual-cognitive skills (i.e., passing accuracy, reaction time, composure, and adaptability) were assessed using a soccer-specific virtual reality simulator, collected pre- and posttrial. Neuromuscular performance (reactive-strength index, vertical jump height, absolute and relative peak power output, and negative vertical displacement) and sprint performance (15 and 30 m) were measured at pretrial, half-time, 90 min, and posttrial. Caffeine gum attenuated declines in reaction time (pre: 90.8 ± 0.8 AU to post: 90.7 ± 0.8 AU) by a further 4.2% than placebo (pre: 92.1 ± 0.8 AU to post: 88.2 ± 0.8 AU; p < .01). Caffeine gum reduced composure by 4.7% (pre: 69.1 ± 0.8 AU to post: 65.9 ± 0.8 AU) versus placebo (pre: 68.8 ± 0.8 AU to post: 68.3 ± 0.8 AU; p < .01). Caffeine gum did not influence any other variables (p > .05). Where caffeine gum is consumed by players prior to extra-time, reaction time increases but composure may be compromised, and neuromuscular and sprint performance remain unchanged. Future work should assess caffeine gum mixes with substances like L-theanine that promote a relaxed state under stressful conditions.

Nutritional habits of professional team sport athletes: An insight into the carbohydrate, fluid, and caffeine habits of English Premier League football players during match play

To better understand the in-match fuelling practices of elite football players and compare against current guidelines, we quantified the carbohydrate, fluid, and caffeine intake of players from an English Premier League club (n = 22) during 90 min of competitive match-play. Mean carbohydrate intake across match-play was 17 ± 11 g.h-1 with players demonstrating a preference towards CHO-containing fluids (58%) when compared with semi-solids (38%) and solids (14%), respectively. CHO intake was significantly lower than reported by players (17 ± 11 vs 24.8 ± 11 g.h-1, p < 0.001) during initial consultation. Fluid was ingested at a rate of 0.45 ± 0.14 L.h-1, with 54, 40 and 6% of ingested fluid coming from water, carbohydrate, and electrolyte-only solutions, respectively. The majority of players (91%) met the UEFA guidelines for fluid consumption. Of the players who consumed caffeine across match-play (55%) the average dose was 233 ± 148 mg (2.8 ± 1.1 mg.kg-1 body mass [BM]), which meets the UEFA consensus guidelines for caffeine intake. Caffeine capsules (42%) and caffeine containing fluids (30%) were the preferred format prior to the warm-up whilst caffeine gum was exclusively used prior to kick-off and during the half-time period (100%). We conclude that 81% of the total playing squad failed to meet the current UEFA CHO intake recommendations of 30-60 g.h-1, which may be attributed to the preference towards fluid-based CHOs as the chosen format of delivery.

Energy expenditure, intake and availability in female soccer players via doubly labelled water: Are we misrepresenting low energy availability?

Female soccer players have been identified as presenting with low energy availability (LEA), though the prevalence of LEA may be overestimated given inaccuracies associated with self-reporting dietary intakes. Accordingly, we aimed to quantify total daily energy expenditure (TDEE) via the doubly labelled water (DLW) method, energy intake (EI) and energy availability (EA). Adolescent female soccer players (n = 45; 16 ± 1 years) completed a 9-10 day 'training camp' representing their national team. Absolute and relative TDEE was 2683 ± 324 and 60 ± 7 kcal kg-1 fat free mass (FFM), respectively. Mean daily EI was lower (P < 0.01) when players self-reported using the remote food photography method (RFPM) (2047 ± 383 kcal day-1) over a 3-day period versus DLW derived EI estimates accounting for body mass (BM) changes (2545 ± 518 kcal day-1) over 7-8 days, representing a mean daily Δ of 499 ± 526 kcal day-1 and 22% error when using the RFPM. Estimated EA was different (P < 0.01) between methods (DLW: 48 ± 14 kcal kg-1 FFM, range: 22-82; RFPM: 37 ± 8 kcal kg-1 FFM, range: 22-54), such that prevalence of LEA (<30 kcal kg-1 FFM) was lower in DLW compared with RFPM (5% vs. 15%, respectively). Data demonstrate the potential to significantly underestimate EI when using self-report methods. This approach can therefore cause a misrepresentation and an over-prevalence of LEA, which is the underlying aetiology of 'relative energy deficiency in sport' (REDs). HIGHLIGHTS: What is the central question of this study? Do self-reported dietary intakes (via remote food photography method, RFPM) overestimate low energy availability (LEA) prevalence in female soccer players compared with energy intake evaluation from the doubly labelled water (DLW) method? What is the main finding and its importance? Estimated energy availability is greater with the DLW method compared with RFPM, such that the prevalence of LEA is greater when self-reporting dietary intakes. Accordingly, data demonstrate the potential to misrepresent the prevalence of LEA, an underlying factor in the aetiology of 'relative energy deficiency in sport' (REDs).

Analysis of Sports Supplement Consumption of Elite Referees of the Spanish Professional Fotball League

BACKGROUND

Sports supplements (SSs) are widely used among team sport athletes; however, evidence supporting the use of SSs among football referees at the elite level is scarce. The aim of the present study was to analyze the consumption of SSs among referees with respect to their level of competition and referee type (main referees (MRs) vs. assistant referees (ARs)).

METHODS

A total of 106 football referees participated in this study, with 46.2% from the First Spanish Division and 53.8% from the Second Spanish Division, representing 84.13% of the total number of referees. Each participant completed a validated questionnaire about SS consumption, with the SSs classified according to the Australian Institute of Sport (AIS) ABCD system: Group A has strong evidence for enhancing athlete health and performance, Group B shows potential benefits but needs more evidence, Group C has inconclusive evidence against use, and Group D includes prohibited substances.

RESULTS

A total of 84.0% of the MRs and ARs reported the consumption of at least one SS. Differences were found only in the consumption of medical supplements between division (p = 0.016) and type of referee (p = 0.041), though no significant differences were found among the remaining AIS SS categories (p > 0.05). Sport performance (49.6%), Internet (41.0%), and dietitian-nutritionists (31.7%) were the primary reason for SS consumption, purchase location, and source of information, respectively. The most frequently consumed SS were whey protein (45.3%), followed by creatine (33.0%), sport bars and sports drinks (28.3%), and caffeine (19.8%).

CONCLUSIONS

MRs and ARs reported a high prevalence of dietary supplement (SS) consumption, with significant differences between division and referee type observed only in medical supplement consumption.

Retirements of professional tennis players in second- and third-tier tournaments on the ATP and WTA tours

The demands of professional tennis, including physical and psychological aspects, contribute to the frequency of retirements at elite levels of the sport. The aim of this study was to analyze epidemiological patterns and risk factors associated with retirements in previous ATP and WTA Tour tournaments. A retrospective cohort study was conducted. This study focused on previous ATP and WTA Tour tournaments. The ATP database encompassed 584,806 matches, while the WTA database included 267,380 matches. To assess retirements, potential risk factors such as playing surface, tournament category, match round, and player age were analyzed. Incidence rates were calculated for the period between 1978-2019 for men and 1994-2018 for women. The overall incidence rate was 1.56 (95%CI: 1.54, 1.59) and 1.36 (95%CI: 1.33, 1.39) retirements per 1000 games played in male and female competitions, respectively. Retirements increased over the years. Higher incidence rates were observed on hard (1.59 [95%CI: 1.56, 1.63] and 1.39 [95%CI: 1.34, 1.44]) and clay (1.60 [95%CI: 1.57, 1.63] and 1.36 [95%CI: 1.32, 1.41]) compared to grass courts (0.79 [95%CI: 0.65, 0.94] and 1.06 [95%CI: 0.88, 1.27]). Risk factors differed by gender, with tournament category significant in males (IRR: 1.23 [95%CI: 1.19, 1.28] in ITF vs ATP) and match round in females (IRR: 0.92 [95%CI: 0.88, 0.98] in preliminary vs final). This study provides valuable insights for coaches, players, support teams, and epidemiologists regarding retirements and associated risk factors in previous ATP and WTA Tour tournaments, contributing to injury prevention strategies.

Recovery during Successive 120-min Football Games: Results from the 120-min Placebo/Carbohydrate Randomized Controlled Trial

PURPOSE

This study aimed to examine the recovery kinetics (i.e., time-dependent changes) of performance-related variables between two 120-min male football games performed 3 d apart with and without carbohydrate supplementation.

METHODS

Twenty male players (20 ± 1 yr; body fat, 14.9% ± 5.1%; maximal oxygen consumption, 59.4 ± 3.7 mL·kg -1 ·min -1 ) participated in two 120-min football games (G1, G2) according to a randomized, two-trial, repeated-measures, crossover, double-blind design. Participants received carbohydrate/placebo supplements during recovery between games. Field activity was monitored during the games. Performance testing and blood sampling were performed before and at 90 and 120 min of each game. Muscle biopsies were collected at baseline and at 90 and 120 min of G1 and pre-G2.

RESULTS

Compared with G1, G2 was associated with reduced total distance (10,870 vs 10,685 m during 90 min and 3327 vs 3089 m during extra 30 min; P = 0.007-0.038), average (6.7 vs 6.2 km/h during extra 30-min game-play; P = 0.007) and maximal speed (32.2 vs 30.2 km/h during 90 min and 29.0 vs 27.9 km/h during extra 30 min; P < 0.05), accelerations/decelerations ( P < 0.05), and mean heart rate ( P < 0.05). Repeated sprint ability ( P < 0.001), jumping ( P < 0.05), and strength ( P < 0.001) performance were compromised before and during G2. Muscle glycogen was not restored at G2 baseline ( P = 0.005). Extended game-play reduced lymphocyte, erythrocyte counts, hematocrit, hemoglobin, reduced glutathione ( P < 0.05) and increased delayed onset of muscle soreness, creatine kinase activity, blood glycerol, ammonia, and protein carbonyls ( P < 0.05) before and during G2. Pax7 + ( P = 0.004) and MyoD + cells ( P = 0.019) increased at baseline G2. Carbohydrate supplementation restored performance and glycogen, reduced glycerol and delayed onset of muscle soreness responses, and increased leukocyte counts and Pax7 + and MyoD + cells.

CONCLUSIONS

Results suggest that extended football games induce a prolonged recovery of performance, which may be facilitated by carbohydrate supplementation during a congested game fixture.

Changes in Body Composition and Nutritional Periodization during the Training Macrocycle in Football-A Narrative Review

Nutrition periodization in football training is an important determinant of adaptation to cyclic training loads. Personalizing an athlete's diet is crucial to ensure optimal performance and body composition, depending on the phase of training. The purpose of this review is to answer the question of how the body composition of football players changes over the training macrocycle and how dietary recommendations should be tailored to specific training periods. The review of scientific evidence was conducted based on the available literature, typing in phrases related to training and nutrition periodization using the PubMed and Google Scholar database methodology tools. A literature search resulted in the selection of 346 sources directly related to the topic of the study, and then those with the highest scientific value were selected. There is a need to adjust energy and nutrient intake according to the different training phases in a football player's preparation cycle. During the preparatory phase, it is recommended to increase protein and energy intake to support anabolic processes and muscle mass development. During the competitive period, due to the intensity of matches and training, the importance of carbohydrates for glycogen replenishment and recovery is emphasized. The transition phase requires the regulation of caloric intake to prevent adverse changes in body composition. Hydration has been identified as a key element in each phase of training. Cooperation between coaches, nutritionists, and players is essential to optimize sports performance and rapid recovery, and the authors recommend continuous adaptation and nutritional optimization as an integral part of football training.

Dietary intake and adherence to the Mediterranean diet in semi-professional female soccer players: a cross-sectional study

Background

Adequate energy and nutrient intakes in athletes contribute to optimal performance and recovery, decrease the risk of injury, and help preserve athletes' health. The Mediterranean diet (MD) is considered suitable for covering the nutritional needs of athletes, while contributing to improve eating habits. The aim of the present study was to investigate the energy and nutrient intakes of semi-professional female soccer players and their adherence to the MD, during the competitive season.

Methods

A cross-sectional observational study was conducted on twenty-three female soccer players, who were invited to fill in a 3-day food diary twice, one month apart, to assess their energy and nutrient intakes and a validated questionnaire (MEDI-LITE) to evaluate their adherence to MD. Exercise energy expenditure during three training and match-play days was monitored by GPS.

Results

On average, the participants consumed 1,981 kcal/day, with 44% of their energy deriving from carbohydrates, 21% from protein, and 34% from fat; the mean MD adherence score was 10.1 ± 1.8, corresponding to a good MD adherence. A substantial percentage of athletes were at risk of insufficient nutrient intakes for vitamin D (100%), iodine (87%), potassium (87%), vitamin E (39%), iron and zinc (17 and 30%, respectively).

Conclusion

The evaluation of the dietary intake in female soccer players showed energy deficiency in relation to training level, mainly due to the insufficient intake of carbohydrates, and micronutrient deficiencies. The technical staff should promote adequate consumption of starchy foods in female athletes and emphasize the importance of a proper distribution of energy intake among different eating occasions, including snacks. Periodic monitoring of the nutritional status of micronutrients (vitamin D and some minerals) could help reduce deficiency risk. Over all, nutrition education to improve eating habits of athletes seems worthy of attention, in order to preserve athletes' health and performance.

The Effects of Acute Deep Seawater Supplementation on Muscle Function after Triathlon

(1) Background: Trainers and athletes have always sought to reduce the failure of muscle function during long endurance events. However, nowadays, it is a topic that is generating much debate in the scientific field. Currently, deep-sea water (DSW) intake seems to be a suitable hydration alternative for this type of endurance event. Therefore, the aim of this study was to determine whether DSW consumption during a triathlon event could preserve muscle function after exercise. (2) Methods: Nineteen trained male triathletes (age = 39.0 ± 4.25 years; BMI = 23.67 ± 1.81 kg/m2) randomly performed three triathlons, one of them consuming DSW (Totum SPORT 30 AB, Laboratories Quinton International, S.L., Spain), the other consuming isotonic placebo and the last with tap water-hydration. A vertical jump test with countermovement and an isometric muscle strength test were conducted before and after the triathlon test. (3) Results: There was a significant difference between treatment × time during the isometric muscle strength test. Based on the Tukey post hoc analysis, the peak net force decreased statistically in the placebo (p = 0.045) and control conditions (p = 0.026), but not in the experimental condition (p = 0.121). In addition, all of the conditions studied obtained similar results in the countermovement vertical jump after exercise. (4) Conclusions: As a result, consumption of DSW seems to delay the failure of muscle function specifically in isometric exercises but does not improve performance in sports. Thus, DSW does not alter muscle capacity in a negative way; therefore, its consumption may be recommended.

'You can change your life through sports'-physical activity interventions to improve the health and well-being of adults experiencing homelessness: a mixed-methods systematic review

OBJECTIVES

Systematically synthesise evidence of physical activity interventions for people experiencing homelessness (PEH).

DESIGN

Mixed-methods systematic review.

DATA SOURCES

EMBASE, Web of Science, CINAHL, PubMed (MEDLINE), PsycINFO, SPORTDiscus and Cochrane Library, searched from inception to October 2022.

ELIGIBILITY CRITERIA

PICO framework: population (quantitative/qualitative studies of PEH from high-income countries); intervention (physical activity); comparison (with/without comparator) and outcome (any health/well-being-related outcome). The risk of bias was assessed using Joanna Briggs Institute critical appraisal tools.

RESULTS

3615 records were screened, generating 18 reports (17 studies, 11 qualitative and 6 quantitative (1 randomised controlled trial, 4 quasi-experimental, 1 analytical cross-sectional)) from the UK, USA, Denmark and Australia, including 554 participants (516 PEH, 38 staff). Interventions included soccer (n=7), group exercise (indoor (n=3), outdoor (n=5)) and individual activities (n=2). The risk of bias assessment found study quality to vary; with 6 being high, 6 moderate, 4 low and 1 very low. A mixed-methods synthesis identified physical and mental health benefits. Qualitative evidence highlighted benefits carried into wider life, the challenges of participating and the positive impact of physical activity on addiction. Qualitative and quantitative evidence was aligned demonstrating the mental health benefits of outdoor exercise and increased physical activity from indoor group exercise. Quantitative evidence also suggests improved musculoskeletal health, cardiovascular fitness, postural balance and blood lipid markers (p<0.05).

CONCLUSION

Qualitative evidence suggests that physical activity interventions for PEH can benefit health and well-being with positive translation to wider life. There was limited positive quantitative evidence, although most was inconclusive. Although the evidence suggests a potential recommendation for physical activity interventions for PEH, results may not be transferable outside high-income countries. Further research is required to determine the effectiveness and optimal programme design.

Exploring the Impact of Alternative Sources of Dietary Nitrate Supplementation on Exercise Performance

An increase in the level of nitric oxide (NO) plays a key role in regulating the human cardiovascular system (lowering blood pressure, improving blood flow), glycemic control in type 2 diabetes, and may help enhance exercise capacity in healthy individuals (including athletes). This molecule is formed by endogenous enzymatic synthesis and the intake of inorganic nitrate (NO3-) from dietary sources. Although one of the most well-known natural sources of NO3- in the daily diet is beetroot (Beta vulgaris), this review also explores other plant sources of NO3- with comparable concentrations that could serve as ergogenic aids, supporting exercise performance or recovery in healthy individuals. The results of the analysis demonstrate that red spinach (Amaranthus spp.) and green spinach (Spinacia oleracea) are alternative natural sources rich in dietary NO3-. The outcomes of the collected studies showed that consumption of selected alternative sources of inorganic NO3- could support physical condition. Red spinach and green spinach have been shown to improve exercise performance or accelerate recovery after physical exertion in healthy subjects (including athletes).

Post-discharge nutritional management for patients with coronary heart disease and frailty: a qualitative study

BACKGROUND

Frail elderly patients experience physiological function and reserve depletion, leading to imbalances in their internal environment, which increases the risk of coronary heart disease recurrence and malnutrition. However, the majority of these patients, who primarily have a low level of education and lack self-management skills, face difficulties actively dealing with obstacles during the transition period after their discharge from hospitalization. Therefore, it is necessary to understand and discuss in depth the nutrition management experience of discharged elderly patients with coronary heart disease and frailty (ages 65-80 years old) and to analyze the promoting and hindering factors that affect scientific diet behavior during the discharge transition period.

METHODS

Fifteen elderly patients with coronary heart disease and frailty who had been discharged from the hospital for 6 months were interviewed using a semistructured method. The directed content analysis approach to descriptive research was used to extract topics from the interview content.

RESULTS

All participants discussed the problems in health nutrition management experience of discharged. Five topics and ten subtopics were extracted, such as ①Weak perceptions and behaviors towards healthy eating (personal habit solidification, negative attitudes towards nutrition management), ②Lack of objective factors for independently adjusting dietary conditions (reliance on subjective feelings, times of appetite change), ③Personal hindrance factors (memory impairment, deficiencies in self-nutrition management), ④Expected external support (assistance care support, ways to obtain nutritional information), ⑤Lack of continuous nutrition management (interruption of professional guidance, avoidance of medical treatment behavior).

CONCLUSIONS

Nutrition management after discharge places a burden on elderly patients with coronary heart disease and frailty. According to the patients' physical conditions, we should develop a diet support system that is coordinated by individuals, families and society.

Supplement Consumption by Elite Soccer Players: Differences by Competitive Level, Playing Position, and Sex

Soccer is a sport practiced all over the world and whose practice begins in young athletes. Currently, the consumption of nutritional supplements is essential to achieve the maximum performance of players. The aim of this study was to describe the consumption of sports supplements (CSS) by elite soccer players and its association with their competitive level, playing position, and sex. A comparative descriptive and non-experimental study was performed during the 2021-2022 competitive season. A total of 70 elite players completed one online questionnaire about their CSS. We found that sports drinks (55.7%), sports bars (50.0%), whey protein (48.6%), caffeine (47.1%), and creatine (60.0%) were the most consumed supplements by the total sample. Relative to the categories, the CSS was higher in the senior teams for both men and women. Regarding playing positions, caffeine was more consumed by midfielders and forwards (p = 0.013). Finally, in relation to sex, significant differences were found in the consumption of sports confectionery (p = 0.036), whey protein (p = 0.002), β-alanine (p = 0.013), and melatonin (p = 0.016). Soccer club SS questionnaires gather data to understand patterns, assess effectiveness and risks, and aid research. In conclusion, differences were found in the CSS according to competitive level, sex, and playing position.

Acute fuelling and recovery practices of academy soccer players: implications for growth, maturation, and physical performance

Academy soccer players frequently train in the evening (i.e. 1700-2000 h), hence limited time to nutritionally prepare and recover due to schooling, travel and sleep schedules. Accordingly, we assessed timing and quantity of energy intake in the pre-training and post-training period. Over a 3-day in-season training period, male players (n=48; n=8 from under (U) 12, 13, 14, 15/16, 18 and 23 players) from an English Premier League academy self-reported dietary intake and physical activity levels (via the remote food photography method and activity diary, respectively) in the four hours pre- and post-training. Timing of pre-training energy intake ranged from 40 ± 28 mins (U15/U16 players) to 114 ± 71 mins (U18) before training and mean carbohydrate (CHO) intake ranged from 0.8±0.4 g.kg-1 (U23) to 1.5±0.9 g.kg-1 (U12). Timing of post-training energy intake ranged from 39 ± 27 mins (U14) to 70 ± 84 mins (U23) and mean CHO intake ranged from 1.6±0.8 g.kg-1 (U12) to 0.9±0.5 g.kg-1 (U14). In contrast to CHO, all age groups consumed sufficient protein intake in the post-training period (i.e. > 0.3 g.kg-1). We conclude academy soccer players habitually practice sub-optimal fuelling and recovery strategies, the consequence of which could impair growth, maturation and physical performance.

Analysis of potential hydration opportunities during future football tournaments based on data from the 2018 FIFA World Cup

The World Cup is traditionally held oppressive thermal conditions. Therefore, teams should follow heat strain mitigation strategies, including optimal fluid ingestion. The objective of this analysis was to assess and visually communicate match-based World Cup player hydration opportunities and behaviors. Broadcast recordings of the 2018 World Cup (June-July) were analyzed. Descriptive data were reported for match duration, the number, type, and duration of breaks, and player-initiated hydration moments, as well as environmental conditions categorized as 'no thermal stress' and 'thermal heat stress.' The median number and interquartile range of total match breaks were 7 [5-8] during official breaks, with a duration of 42 [23-72] seconds. There were 2 [1-3] player-initiated hydration moments per game, with a duration of 77 [55-100] seconds. On top of the 29% (#126) of breaks in which drinking occurred, an additional 26% (#33) of self-initiated drinking was registered with a duration of 7 [4-28] seconds without an official break. There was no significant difference (P = 0.22) in self-initiated hydration between thermal conditions. Relative percentages showed suboptimal use of substitution (14%) and VAR (38%) breaks vs. injury breaks (75%). In conclusion, football players did not sufficiently use available breaks to hydrate.

Prevalence of sports supplements consumption and its association with food choices among female elite football players

OBJECTIVES

The present study aimed to 1) investigate the consumption of Sports Supplements (SSs) among female elite football players, 2) evaluate the influence of age on SS consumption, and 3) determine the relationship between the consumption of SSs and dietary choices among elite football players.

METHODS

A total of 126 female football players of Primera Iberdrola and Reto Iberdrola who participated in this descriptive, observational, and cross-sectional study completed a self-administered questionnaire on SSs and the Athletes' Food Choices Questionnaire.

RESULTS

Overall, 84.1% of participants consumed supplements, mainly for improved sports performance (68.3%) and health (34.1%). The main sources of purchase were the Internet (34.9%) and specialized shops (23.8%), and players were commonly advised by a dietitian-nutritionist to use SSs (56.3%). The SSs most often consumed included whey protein (30.2%), sports drinks (28.6%), creatine monohydrate (28.6%), sports bars (27.8%), and caffeine (27.8%). Older players consumed more supplements at the time of data compilation. Players predominantly acquired these supplements by using the Internet and reported benefits from their use (all P ≤ 0.036). Additionally, players who consumed SSs conveyed more concern about their food choices.

CONCLUSIONS

A high prevalence of female football players consumed SSs, particularly SSs supported by robust scientific evidence. Older players had higher supplement consumption rates. The use of SSs was related to food choices through nutritional characteristics of foods, knowledge about health and nutrition, weight control with the help of food, and the performance benefits players could acquire.

Energy expenditure and dietary intake in professional female football players in the Dutch Women's League: Implications for nutritional counselling

In contrast to male football players, research on the nutritional requirements of female football players is limited. This study aimed to assess total daily energy expenditure (TDEE) in professional female football players, along with body composition, physical activity and dietary intake. This observational study included 15 professional football players playing in the highest Dutch Women's League. TDEE was assessed by doubly labelled water over 14 days, along with resting metabolic rate (RMR; ventilated hood), fat-free mass (FFM; dual-energy x-ray absorptiometry), and dietary intake (24-h recalls). Physical activity energy expenditure (PAEE) was derived from subtracting RMR and estimated diet-induced thermogenesis (10%) from TDEE. TDEE was 2882 ± 278 kcal/day (58 ± 5 kcal/kg FFM) and significantly (p < 0.05) correlated with FFM (r = 0.62). PAEE was 1207 ± 213 kcal/d. Weighted energy intake was 2344 kcal [2023-2589]. Carbohydrate intakes were 3.2 ± 0.7, 4.4 ± 1.1 and 5.3 ± 1.9 g/kg body mass for rest, training and match days, respectively, while weighted mean protein intake was 1.9 ± 0.4 g/kg body mass. In conclusion, the energy requirements of professional female football players are moderate to high and can be explained by the substantial PAEE. To fuel these requirements, sports nutritionists should consider shifting the players' focus towards prioritizing adequate carbohydrate intakes, rather than emphasizing high protein consumption.

Role of the Menstrual Cycle on Performance and Injury Risk: A Survey of Female Professional Rugby Players in the United Kingdom

BACKGROUND

Female athletic performance and injury risk is impacted by variations in the menstrual cycle (MC), but the understanding of the impacts and mechanisms influenced by the menstrual cycle on exercise performance are not fully delineated.

AIMS AND OBJECTIVES

Evaluate associations between the menstrual cycle, perceived performance, and injury risk of elite female rugby players using an online survey.

METHODS

An anonymous online questionnaire was completed by 150 elite female rugby players from two English rugby leagues, the Betfred Women's Super League (BWSL) and the Allianz Premier 15s (AP15s). The collected data were analysed thematically.

RESULTS

The Chi-square test was used to assess associations between age groups and contraception usage, weight change, and training and playing performance; none of the associations were statistically significant (all p values > 0.05). Thematic analysis of 11,660 words of data revealed four themes: (a) MC impact on training and competition, (b) education and period management plans, (c) openness of conversations and comfort taking time off, and (d) injury risk. The impacted performance areas were physical (83.7%), psychological (85.7%), and nutritional (80.3%); players experienced decreased appetite, nausea, fatigue, strength declines, heighted emotions, and worsened focus. In total, 87.8% of athletes perceived the MC to negatively impact performance, 85.7% of players desired to be educated further to prevent injuries, improve nutrition, and training adaptions, 51.7% of participants perceived risk of injury to be higher during MC, and 86.4% of participants did not feel comfortable taking time off due to the MC, worrying that selection would be affected and about opinions from others.

CONCLUSION

A clear negative impact on perceived performance and injury risk was reported by survey participants. The interaction of physical, psychological, and nutritional factors, and a lack of awareness and education emphasise the need for further comprehensive studies and interventions, with measures such as MC monitoring and profiling, education, and training adaptions to develop openness, knowledge, and understanding.

Body Composition Changes in Male and Female Elite Soccer Players: Effects of a Nutritional Program Led by a Sport Nutritionist

BACKGROUND

Soccer is a game in constant evolution and the intensity of play is increasing. Nutrition can play a role in the physical performance of elite players, maintaining their health and facilitating recovery. It is important to cover players' energy demands, and low energy availability may therefore result in impaired performance. This study aimed to evaluate alterations in body composition to determine the effects of a nutritional program led by a sport nutritionist.

METHODS

A group of 88 elite soccer players from a Serie A club in Italy (44 males aged 26.5 ± 3.0 years and 44 females aged 27.1 ± 5.2 years) were enrolled. To evaluate changes in body composition, bioimpedance and anthropometric measurements were obtained following the protocol of the International Society for the Advancement of Kinanthropometry (ISAK).

RESULTS

Compared with females, males had more muscle mass and less fat mass in both seasons evaluated. Comparing the first and last seasons, the male soccer players showed increased muscle mass and decreased fat mass while the female soccer players only showed decreased fat mass.

CONCLUSIONS

The presence of a specialist sport nutritionist on the staff of professional soccer clubs could be important to ensure energy availability and evaluate body composition during the season.

Dietary Intake of Soccer Players before, during and after an Official Game: Influence of Competition Level and Playing Position

Physical demands in soccer differ according to league level and playing position and may influence nutritional requirements. This study examined the effect of competition level and playing position on dietary intake in male soccer players (SP). Diet was weighed and recorded by 123 SP for 3 days; before, on the day, and the day after an official match. SP in the Super League (SL, n = 33) division reported higher (p < 0.05) average three-day energy (195 ± 36 kJ/kg), carbohydrate (6.0 ± 1.1 g/kg), and protein (2.2 ± 0.5 g/kg) intakes compared to the intakes reported by SP in the 2nd (n = 30) (energy: 159 ± 31 kJ/kg; carbohydrate: 4.6 ± 1.2 g/kg; protein: 1.9 ± 0.4 g/kg), 3rd (n = 30) (energy: 153 ± 34 kJ/kg; carbohydrate: 4.5 ± 1.2 g/kg; protein: 1.7 ± 0.4 g/kg), and 4th (n = 30) (energy: 152 ± 36 kJ/kg; carbohydrate: 4.2 ± 1.2 g/kg; protein: 1.7 ± 0.5 g/kg) national leagues (mean ± SD). Furthermore, when data were analyzed by playing position (pooled data), wide midfielders reported higher (p < 0.05) energy (183 ± 33 kJ/kg), carbohydrate (5.4 ± 1.2 g/kg), and fat (1.5 ± 0.4 g/kg) intakes compared to central defenders (energy: 147 ± 37 kJ/kg; carbohydrate: 4.1 ± 1.1 g/kg; fat: 1.2 ± 0.4 g/kg). The dietary intake of SP may differ according to the playing position and competition level, possibly due to different metabolic demands in training and competition.

Pattern of Consumption of Sports Supplements of Spanish Handball Players: Differences According to Gender and Competitive Level

(1) Background: Given the physiological characteristics of handball, players may require the use of certain sports supplements (SS). However, very few studies have investigated the consumption of SS in handball. The aims were to determine the number of handball players who consume SS, to analyze their SS consumption pattern according to gender and competitive level, and to assess whether the SS they consume are supported by scientific evidence, and to which group they belong according to the classification of the Australian Institute of Sport (AIS). (2) Methods: A descriptive-correlational study was carried out on the habitual consumption of SS in 360 federated Spanish players by using a self-administered and validated questionnaire. (3) Results: These showed 65.8% of the sample consumed SS. According to the total number of participants, the most consumed supplements were from Group A: sports drinks (30.8%) and whey protein (30.4%). When analyzing the data by gender, the men's consumption was significantly higher for whey protein (p < 0.001), caffeine (p = 0.009), and creatine monohydrate (p < 0.001). When analyzed by competitive level, the provincial category players group showed a significantly lower consumption than the rest of the groups for protein bars (p = 0.038), whey protein (p = 0.005) and creatine monohydrate (p < 0.001), while the honor division group showed a significantly higher intake of creatine monohydrate than the remaining groups (p < 0.001). (4) Conclusions: The handball players showed a moderate consumption of SS, without using substances that were not supported by scientific evidence and opting in most cases for supplements belonging to group A from the AIS classification. Men tended to consume more SS, and SS consumption increased based on competitive level.

Personality Determinants Related to the Use of Selective and Effective Dietary Supplements by Elite Polish Team Sport Athletes

INTRODUCTION

The purpose of this research was to analyse relationships between personality traits and the use of selected dietary supplements among Polish athletes training in team sports. This subject matter has not been explored in prior research.

MATERIAL AND METHODS

This research was carried out among a group of 213 athletes (men) in the 18-36 age range, with the implementation of a proprietary validated questionnaire for the use of dietary supplements and the NEO-PI-R inventory (Neuroticism-Extraversion-Openness Personality Inventory-Revised). Statistical analyses were performed with the Kruskal-Wallis and Mann-Whitney tests, assuming the following level of significance: α = 0.05.

RESULTS

It was shown that athletes who periodically and regularly consumed isotonic drinks, as well as energy bars and gels, were characterised by a lower level of neuroticism than those who did not consume them. Athletes who periodically took multivitamin preparations were characterised by a lower level of extraversion and openness, and those periodically using multimineral preparations were characterised by a higher level of agreeableness than those who did not use these agents. Athletes not taking creatine were characterised by the lowest level of conscientiousness among the study participants. The use of protein nutrients, probiotics and caffeine was not associated with any personality traits in the athletes.

CONCLUSIONS

Further relationships of the Big Five personality traits were demonstrated with the use of effective dietary supplements by athletes; the most unambiguous correlations were described for neuroticism and conscientiousness in such a way that the use of isotonic drinks, as well as energy bars and gels, was connected with a low level of neuroticism, while the use of creatine was connected with high conscientiousness.

Nitric Oxide in the Field: Prevalence and Use of Nitrates by Dietitians and Nutritionists in Spanish Elite Soccer

Soccer players make frequent use of dietary supplements to improve performance. One of the most widely used strategies to optimize performance is to increase the bioavailability of nitric oxide through nitrates, as it could delay fatigue during physical exertion, among other benefits. This may be positive for performance in soccer, although there is almost no research in professional soccer. The aim of the study was to evaluate the use of nitrates and behaviours related to their consumption in Spanish elite soccer clubs. Dietitian-nutritionist representatives from 45 teams from the most important Spanish soccer leagues completed an online survey to determine if, when, how and why nitrates are prescribed to soccer players. Of the total sample, 55.6% indicated providing nitrates, always before matches, but only 36% in training. There was a wide variation and lack of consistency in the timing, dosage and form of administration of nitrates. The use of mouthwashes or the protocol of chronic nitrate intake was not taken into account in most cases. The present study indicates a lack of interpretation between scientific knowledge and its application in practice, highlighting the need for future research to better understand how to optimize the use of nitrates in professional soccer.

Effects of dietary supplements on athletic performance in elite soccer players: a systematic review

Dietary supplements are widely used among athletes, and soccer players are no exception. Nevertheless, evidence supporting the use of dietary supplements aiming to enhance performance in soccer is somewhat contradictory, scarce, or even nonexistent. Thus, the present study aimed to systematically review and synthesize the effects of dietary supplements on athletic performance (e.g. distance covered, sprinting, jump performance) in elite soccer players. Studies enrolling highly trained, elite, and world-class soccer players using dietary supplements were searched in MEDLINE/PubMed, Web of Science, Scopus, and EBSCO databases in June 2022. In total, 1043 studies were identified, and 18 met the eligibility criteria. The studies evaluated the impacts on athletic performance of several dietary supplements, including caffeine, creatine, protein, beverages with carbohydrates and electrolytes, tart cherry juice, nitrate-rich beetroot juice, sodium bicarbonate with minerals, yohimbine, and a proprietary nutraceutical blend. Caffeine supplementation in doses between 3 and 6 mg/kg of body mass may improve jump height and sprint ability, particularly in female players, but individual response to caffeine must be considered. Creatine may improve sprint, agility, and in female players, jump performance. Protein supplementation can improve sprint and jump performance between matches, especially if protein ingested from food is not up to recommendations. Beverages containing carbohydrates and electrolytes can be used as part of the strategies to achieve carbohydrate intake during training and match-days but used alone do not benefit athletic performance. Tart cherry juice might be useful for maintaining athletic performance after matches that produce higher force loss and exercise-induced muscle damage, although polyphenols from the diet might attenuate the effects of tart cherry supplementation. Nitrate-rich beetroot concentrate can attenuate performance decrease in the days following matches. Further investigation with sodium bicarbonate alone is necessary, as supplementation protocols with elite players included other substances. Finally, the available data does not support yohimbine supplementation or the use of Resurgex Plus® to improve athletic performance in elite soccer players. Still, more well-designed research with elite soccer players is needed to improve support and advice regarding the use of dietary supplements for athletic performance enhancement.

Competitive season effects on polyunsaturated fatty acid content in erythrocyte membranes of female football players

BACKGROUND

An optimal and correctly balanced metabolic status is essential to improve sports performance in athletes. Recent advances in omic tools, such as the lipid profile of the mature erythrocyte membranes (LPMEM), allow to have a comprehensive vision of the nutritional and metabolic status of these individuals to provide personalized recommendations for nutrients, specifically, the essential omega-3 and omega-6 fatty acids, individuating deficiencies/unbalances that can arise from both habitual diet and sportive activity. This work aimed to study the LPMEM in professional female football players during the football season for the first time and compare it with those defined as optimal values for the general population and a control group.

METHODS

An observational study was carried out on female football players from the Athletic Club (Bilbao) playing in the first division of the Spanish league. Blood samples were collected at three points: at the beginning, mid-season, and end of the season for three consecutive seasons (2019-2020, 2020-2021, and 2021-2022), providing a total of 160 samples from 40 women. The LPMEM analysis was obtained by GC-FID by published method and correlated to other individual data, such as blood biochemical parameters, body composition, and age.

RESULTS

We observed a significant increase in docosahexaenoic acid (DHA) (p 0.048) and total polyunsaturated fatty acid (PUFA) (p 0.021) in the first season. In the second season, we observed a buildup in the membrane arachidonic acid (AA) (p < .001) and PUFA (p < .001) contents when high training accumulated. In comparison with the benchmark of average population values, 69% of the football players showed lower levels of omega-6 dihomo-γ-linolenic acid (DGLA), whereas 88%, 44%, and 81% of the participants showed increased values of AA, eicosapentaenoic acid (EPA), and the ratio of saturated and monounsaturated fatty acids (SFA/MUFA), respectively. Regarding relationships between blood biochemical parameters, body composition, and age with LPMEM, we observed some mild negative correlations, such as AA and SFA/MUFA ratio with vitamin D levels (coefficient = -0.34 p = .0019 and coefficient = -.25 p = .042); DGLA with urea and cortisol (coefficient = -0.27 p < .006 and coefficient = .28 p < .0028) and AA with age (coefficient = -0.33 p < .001).

CONCLUSION

In conclusion, relevant variations in several fatty acids of the membrane fatty acid profile of elite female football players were observed during the competitive season and, in comparison with the general population, increased PUFA contents were confirmed, as reported in other sportive activities, together with the new aspect of DGLA diminution, an omega-6 involved in immune and anti-inflammatory responses. Our results highlight membrane lipidomics as a tool to ascertain the molecular profile of elite female football players with a potential application for future personalized nutritional strategies (diet and supplementation) to address unbalances created during the competitive season.

Carbohydrate Nutrition and Skill Performance in Soccer

In soccer, players must perform a variety of sport-specific skills usually during or immediately after running, often at sprint speed. The quality of the skill performed is likely influenced by the volume of work done in attacking and defending over the duration of the match. Even the most highly skilful players succumb to the impact of fatigue both physical and mental, which may result in underperforming skills at key moments in a match. Fitness is the platform on which skill is performed during team sport. With the onset of fatigue, tired players find it ever more difficult to successfully perform basic skills. Therefore, it is not surprising that teams spend a large proportion of their training time on fitness. While acknowledging the central role of fitness in team sport, the importance of team tactics, underpinned by spatial awareness, must not be neglected. It is well established that a high-carbohydrate diet before a match and, as a supplement during match play, helps delay the onset of fatigue. There is some evidence that players ingesting carbohydrate can maintain sport-relevant skills for the duration of exercise more successfully compared with when ingesting placebo or water. However, most of the assessments of sport-specific skills have been performed in a controlled, non-contested environment. Although these methods may be judged as not ecologically valid, they do rule out the confounding influences of competition on skill performance. The aim of this brief review is to explore whether carbohydrate ingestion, while delaying fatigue during match play, may also help retain sport soccer-specific skill performance.

Hydration and Body Composition in Sports Practice: An Editorial

Assessing hydration status and monitoring body composition represent crucial aspects when discussing the advantages of embracing a healthy lifestyle, given its significant impact on both health and sports performance [...].

The Influence of Somatic Maturity on Anthropometrics and Body Composition in Youth Soccer Players

The primary aim of this investigation was to compare players' anthropometric (AP) and body composition (BC) characteristics between distinct maturity bands (pre-PHV, circa-PHV, post-PHV) in youth elite soccer. This study considered 320 male soccer players (mean age 13.8 y). Participants were from U14 (n = 157) and U15 (n = 163) age categories. The Khamis-Roche method was applied to calculate the percentage of predicted adult height (PAH) at the time of assessment based on which the players were further divided into maturity bands (pre-PHV ≤ 87%, circa-PHV = 88-95%, post-PHV > 95%). The findings indicated that most of the players were in the circa-PHV stage at the time of investigation. Measurements included height and weight. The estimates of BC parameters were derived using bioelectrical impedance (BIA) analysis. These various AP and BC attributes displayed significant differences among the maturity bands (F = 139.344-7.925; p < 0.001; large effect sizes) except in body fat mass (BFM) (F = 2.998; p = 0.051; small effect size). The current somatic maturity stage of the athletes should be considered when evaluating BC results, otherwise there is a risk of misinterpretation.