Carbohydrate Nutrition and Team Sport Performance

Nutrition in CrossFit® - scientific evidence and practical perspectives: a systematic scoping review

BACKGROUND

CrossFitⓇ sessions and competitions are characterized by high-intensity challenges that combine aerobic and anaerobic activities with short recovery periods. As a result, effective nutritional practices play a crucial role in optimizing performance and enhancing recovery. Therefore, nutritional practices are central to optimizing performance and accelerating recovery. This review aims to summarize current evidence on nutritional and ergogenic aid responses to CrossFitⓇ practice.

METHODS

The search was conducted in four electronic databases (PubMed, Web of Science, Scopus and SportDiscus). Gray literature was also extracted for studies exploring the nutritional habits of CrossFitⓇ participants as well as the ingestion of ergogenic aids. In addition, a meta-analysis was conducted to examine the impacts of dietary habits and ergogenic aids on performance.

RESULTS

Forty-nine studies met the eligibility criteria and were included in the current review. Carbohydrate intake was below the recommendations for athletes, although protein ingestion remains adequate. High-carbohydrate diets had a positive effect on CrossFitⓇ performance. The evidence concerning the effects of a ketogenic diet on performance is limited. When used prior to or during the workout, the impact of carbohydrates on CrossFitⓇ performance was negligible, whereas the effect of caffeine was significant. Ergogenic aids, particularly creatine and protein, are commonly used by CrossFitⓇ participants.

CONCLUSION

The standard diets recommended to CrossFitⓇ participants need to be revised because they are characterized by lower values of carbohydrates. Caffeine should be used prior to or during the CrossFitⓇ sessions. Regarding the impact of ergogenic aids on recovery, future studies are needed.

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.

Sports Nutrition Knowledge and Carbohydrate Intake in Young Male Elite Football Players: Insights from a Case Study of HNK Hajduk Academy

Background: Proper nutrition is crucial for optimizing performance and recovery in elite young football players. This study aimed to assess sports nutrition knowledge, adherence to the Mediterranean diet (MD), and carbohydrate intake across different training phases, evaluating their relations with match performance. Methods: Thirty-three male HNK Hajduk academy players (15-19 years) completed a nutrition questionnaire and a seven-day food diary, while performance metrics were analyzed using GPS tracking. Results: The results showed that sports nutrition knowledge was generally low (43.0 ± 17.0%), with significant misconceptions about carbohydrate fueling strategies. Players significantly overestimated their MD adherence, with a self-reported KIDMED index (6.06 ± 2.41) notably higher than the corrected score derived from food diaries (4.21 ± 2.53, p < 0.001). Carbohydrate intake was suboptimal on match-related days (3.64 g/kg on match day, 4.45 g/kg on the day before), failing to meet the recommended minimum of 6 g/kg per day. Regression analysis predicted that energy (β = 0.83; p = 0.02) and carbohydrate intake (β = 0.69; p = 0.03) on match day significantly predicted distance covered per minute, with a positive relationship observed for both outcomes, highlighting its impact on endurance. However, no significant relationship was found between carbohydrate intake and maximum sprint speed. Conclusions: These findings underscore the need for structured nutrition education within football academies to enhance players' dietary habits and performance outcomes. Future research should focus on longitudinal interventions to assess how improved nutrition knowledge influences dietary adherence and athletic performance over time. Although knowledge of sports nutrition is fundamental, practical training and education to improve dietary competencies are crucial for athletes to effectively apply this knowledge in daily training and match preparations.

Nutrition knowledge, supplementation practices and access to nutrition supports of collegiate student athletes in Ireland

PURPOSE

To provide a comprehensive assessment of nutrition knowledge, supplementation practices and access to nutrition supports in third-level/university student athletes in Ireland.

METHODS

Nutrition knowledge was assessed using the Abridged Nutrition for Sport Knowledge Questionnaire (ANSKQ), with additional questions on nutrition information sources, access to nutritional supports and supplement use.

RESULTS

138 student athletes completed the online questionnaire. Participants had a mean (± SD) Total Nutrition Knowledge (TNK) score of 51.6 ± 13.7%, classed as "average". Scores were higher in the General Nutrition Knowledge (GNK) (61.4 ± 15.4%) sub-section, while Sports Nutrition Knowledge (SNK) scores (47.2 ± 15.5%) were considered "poor". Athletes that studied nutrition/dietetics at university level had higher GNK (69.9 ± 12.3% vs. 60.3 ± 15.5%), SNK (61.5 ± 13.7% vs. 45.3 ± 14.8%) and TNK (64.1 ± 11.8% vs. 50.0 ± 13.1%) scores than other students (all p < 0.05). Athletes with prior nutrition education/training also had significantly better TNK, GNK and SNK scores than those with no previous education/training (p < 0.001). Dietary supplements were used by 62.4% of participants, 64.0% of whom used 3 or more supplements. The most popular supplements were protein (77.9%), vitamin D (47.7%) and multivitamins (47.7%). Only 49.3% of participants had previous access to nutrition supports, but 80.4% of participants wanted more support.

CONCLUSIONS

Student athletes demonstrated inadequate levels of nutrition knowledge, particularly in the areas of sports nutrition, coupled with a high prevalence of nutritional supplement use. Athletes with higher education levels and prior nutrition education/training demonstrated greater nutrition knowledge, although a high desire for more nutrition supports was reported by the athletes in this cohort.

An investigation into how the timing of nutritional supplements affects the recovery from post-exercise fatigue: a systematic review and meta-analysis

Background

This study used a systematic evaluation and meta-analysis to determine how the timing of nutritional supplements affected the recovery from post-exercise weariness. A vital component of enhancing athletic performance and advancing health is post-exercise recovery, where nutritional supplements are crucial. Although it has been demonstrated that supplementing timing may affect recovery outcomes, there is conflicting evidence about the best time to take supplements.

Methods

We thoroughly searched several academic databases and screened for inclusion of randomized controlled trials, clinical trials, and observational studies that satisfied the criteria in order to examine the effects of varying nutritional supplementation timing (immediate vs. delayed supplementation) on fatigue recovery.

Results

The findings demonstrated that, in comparison to delayed supplementation, protein and carbohydrate supplementation right after exercise dramatically expedited muscle recovery, glycogen recovery, and decreased tiredness. Furthermore, the impact of supplementation timing on recovery effects differed depending on the individual and the type of exercise (e.g., strength training, endurance exercise, and high-intensity interval training).

Conclusion

Recovery from post-exercise weariness is significantly impacted by the timing of nutritional intake. Supplementing with protein and carbohydrates right after exercise, particularly after intense exercise, can help with tiredness relief, muscle recovery, and glycogen replenishment.

[Effects of intermittent fasting and sports performance: a narrative review]

Introduction

Recently, fasted exercise has generated interest for its potential to stimulate metabolic and performance adaptations. The present study aims to analyze the effects of fasting and fasted training on performance and metabolism, acutely and chronically. The databases Medline (PubMed), Physiotherapy Evidence Database (PEDro), Cochrane, and Google Scholar were searched. In total, 767 studies were identified. Of those, 51 studies were finally included. Acutely, exercise on fasting promotes fat oxidation at low and moderate intensities, while protein catabolism is not increased. Performance is not affected in efforts lower than 1 hour. Chronically, fasting generates greater efficiency in fat metabolism and the ability to regulate blood glucose in the long term, although it has not been possible to determine whether these findings improve sports performance. More research is needed in elite athletes, with high training loads and with a periodized approach to fasting.

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.

Microwave-Heating-Assisted Synthesis of Ultrathin and Ultralong Hydroxyapatite Nanowires Using Biogenic Creatine Phosphate and Their Derived Flexible Bio-Paper with Drug Delivery Function

With an ultrahigh aspect ratio and a similar chemical composition to the biomineral in bone and tooth, ultralong hydroxyapatite nanowires (UHAPNWs) exhibit a meritorious combination of high flexibility, excellent mechanical performance, high biocompatibility, and bioactivity. Despite these exciting merits, the rapid and green synthesis of UHAPNWs remains challenging. In this work, we have developed an environment-friendly, rapid, and highly efficient synthesis of ultrathin UHAPNWs by the microwave-assisted calcium oleate precursor hydrothermal method using biogenic creatine phosphate as the bio-phosphorus source. Owing to the controllable hydrolysis of bio-phosphorus-containing creatine phosphate and the highly efficient heating of microwave irradiation, ultrathin UHAPNWs with a homogeneous morphology of several nanometers in diameter (single nanowire), several hundred micrometers in length, and ultrahigh aspect ratios (>10,000) can be rapidly synthesized within 60 min. This effectively shortens the synthesis time by about two orders of magnitude compared with the traditional hydrothermal method. Furthermore, ultrathin UHAPNWs are decorated in situ with bioactive creatine and self-assembled into nanowire bundles along their longitudinal direction at the nanoscale. In addition, ultrathin UHAPNWs exhibit a relatively high specific surface area of 84.30 m2 g-1 and high ibuprofen drug loading capacity. The flexible bio-paper constructed from interwoven ibuprofen-loaded ultrathin UHAPNWs can sustainably deliver ibuprofen in phosphate-buffered saline, which is promising for various biomedical applications such as tissue regeneration with anti-inflammatory and analgesic functions.

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.

Contemporary Themes in Dietary Intake in Rugby Union Players: A Narrative Review

Rugby union is an intermittent team sport with variability in body composition and match-play demands between positions which requires careful consideration for individual dietary requirements. While previous reviews have detailed the macronutrient intake in rugby players, none have discussed the further determinants of dietary intake in this population. Therefore, the purpose of the current review was to summarise the current evidence detailing dietary intake in rugby union players, report on contemporary nutritional research themes, and provide recommendations for athletes, nutritionists, and other stakeholders. In total, eighteen articles report on dietary intake in rugby players, with only one of these detailing dietary intake in female athletes. Recent studies have reported on both protein and carbohydrate periodisation practices in rugby union players; however, there is currently limited evidence as to the influence of these on performance, recovery, and well-being. Factors influencing eating patterns, the impact of sports nutritionists on dietary intake, and food consumption in catered and non-catered environments has been explored in isolated studies. Nutrition knowledge levels in rugby players have been reported in several studies; however, the influence this has on dietary intake in rugby players is unknown. Collectively, despite new contemporary themes emerging in the literature concerning dietary intake in rugby players, the studies are isolated; as such, there is limited scope to the translatability of information due to heterogeneity in sex, level of play, and location of participants. Given this, future research should aim to build upon the themes identified in this review in combination to support practitioners working within their specific environments. This will subsequently build towards the generation of rugby-specific recommendations.

The Impact Plant-Based Diets Have on Athletic Performance and Body Composition: A Systematic Review

Plant-based diets have gained popularity among athletes in recent years. Some believe that plant-based diets will improve performance owing to higher intakes of carbohydrates and antioxidants. Some believe it that will harm performance due to lower intakes of complete protein and creatine. This systemic review was conducted using Covidence software. A literature search of PubMed, Embase (Elsevier), CINAHL Plus (EBSCO), and Web of Science was completed on 22 March 2022. Following the development of clear objectives and a research question that identified the population, intervention, comparison, and outcomes, initial search criteria and keywords were identified. Extracted results totaled 2249, including 797 duplicates. The initial screening resulted in 1437 articles being excluded. The remaining 15 articles proceeded to full-text screening. A final 8 articles were included in the review, with 7 excluded. This paper will review the impact plant-based diets have on athletic performance and body composition in healthy young adults aged 18 to 45 years.

Kinanthropometry and dietary habits of non-professional rugby players

Introduction

Evaluating the body composition and dietary habits of non-professional athletes can help identify areas for improvement to enhance sports performance. The present study aimed to describe the anthropometric and body composition features, as well as the dietary habits, of non-professional rugby players in Argentina.

Methods

Fifty-seven rugby players from a Group III Club of the Unión de Rugby de Buenos Aires (URBA) were assessed using extensive anthropometric measurements according to the International Society for the Advancement of Kinanthropometry (ISAK) protocol. Reference data from professional rugby players in Group I clubs were used as a control for body composition comparisons. Dietary intake was evaluated using the 24-h recall method, and nutrient analysis was performed with SARA software.

Results

Non-professional rugby players were shorter (Forwards: 175.9 vs. 181.5 cm; Backs: 172.5 vs. 175.7 cm), had higher body fat percentages (Forwards: 16.4 vs. 12.3%; Backs: 11.0 vs. 9.3%), and were less muscular (Forwards: 46.0 vs. 48.8%; Backs: 48.4 vs. 50.2%) compared to professional rugby players. The average dietary intake was 3,363 Kcal, with protein and carbohydrate intakes of 1.4 g kg-1 day-1 and 4.1 g kg-1 day-1, respectively, and 35% of energy intake from fat. Backs reported a higher caloric intake than forwards (3,682 vs. 2,827 Kcal). There was a high prevalence of insufficient intake of calcium (58%), vitamin A (49%), and vitamin C (65%), the latter two corresponding with a low intake of fruits and vegetables (6% of total energy intake). Meal pattern analysis showed that 46% of total energy was ingested at dinner.

Conclusions

The body composition of non-professional rugby players from low-income clubs could be improved to enhance rugby performance, as compared to players in more competitive tiers. Economic constraints might contribute to a sub-optimal nutritional profile, potentially affecting body composition and on-field performance negatively. Recommendations to improve dietary intake should be made considering the budget constraints of these players.

Effect of Off-Season Iron Supplementation on Aerobic Capacity of Female Handball Player: A Randomized, Double-Blinded, Placebo-Controlled Study

Background

Iron supplementation, especially in female athletes, is 1 of the influential factors in aerobic capacity, and its deficiency can lead to significant problems related to reduced aerobic capacity.

Objectives

This study aimed to investigate the effect of 3 wk of iron supplementation on the aerobic capacity of female handball players.

Methods

In this randomized, double-blinded, and placebo control trial, 14 elite handball players (age: 21.6 ± 5.68 y; height: 169.5 ± 4.9 cm; weight: 62.2 ± 9.25 kg; body mass index (in kg/m2): 21.5 ± 2.9) randomly divided into 2 supplement groups (receiving a 100 mg/d of poly-maltose tri hydroxide iron complex in the form of tablets) and the placebo group (receiving a tablet containing 100 mg/d starch which is the same color and shape as iron tablets). The supplementation protocol was performed for 3 wk during the off-season. Maximal oxygen consumption (VO2max), amounts of carbon dioxide at the first ventilatory threshold, amounts of carbon dioxide at the second ventilatory threshold, time to exhaustion (TTE), pulmonary ventilation (VE), ventilatory equivalents for oxygen, amounts of oxygen at the first ventilatory threshold, amounts of oxygen at the second ventilatory threshold, time to reach first ventilatory threshold, end-tidal partial pressure of oxygen at the first ventilatory threshold, end-tidal partial pressure of carbon dioxide at the first ventilatory threshold and ventilatory equivalents for carbon dioxide were measured using the Bruce test and gas analyzer in 2 pretest and posttest stages.

Results

There were significant improvements in oxygen at the first ventilatory threshold, time to reach first ventilatory threshold, and end-tidal partial pressure of carbon dioxide at the first ventilatory threshold and a significant decrease in end-tidal partial pressure of oxygen at the first ventilatory threshold (P < 0.05). Also, no significant changes were found in VO2max, carbon dioxide at the first ventilatory threshold, carbon dioxide at the second ventilatory threshold, oxygen at the second ventilatory threshold, TTE, VE, ventilatory equivalents for oxygen, and ventilatory equivalents for carbon dioxide after 3 wk of iron supplementation (P > 0.05).

Conclusions

The study found that 3 wk of off-season iron supplementation positively impacted female handball players' aerobic capacity; however, it did not significantly improve their VO2max.

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.

Metabolic, cognitive and neuromuscular responses to different multidirectional agility-like sprint protocols in elite female soccer players - a randomised crossover study

PURPOSE

Resistance to fatigue is a key factor in injury prevention that needs to be considered in return-to-sport (RTS) scenarios, especially after severe knee ligament injuries. Fatigue should be induced under game-like conditions. The SpeedCourt (SC) is a movement platform for assessing multidirectional sprint performance, typical of game-sports, due to change-of-direction movements in response to a visual stimulus. Designing adequate fatigue protocols requires the suitable arrangement of several loading variables such as number of intervals, sprint distance or work/relief ratio (W:R). Therefore, this study analysed the acute fatigue effects of different SC protocols on metabolic load, cognitive function and neuromuscular performance.

METHODS

Eighteen female soccer players (mean ± SD; age: 23.1 ± 4.6 years) of the 1st German Division participated in this randomised, crossover study. Using a random allocation sequence, players completed four volume-equated protocols differing in W:R and sprint distance per interval (P1:12 × 30 m, W:R = 1:2 s; P2:12 × 30 m, W:R = 1:3 s; P3:18 × 20 m, W:R = 1:2 s; P4:18 × 20 m, W:R = 1:3 s). Pre- and post-exercise, metabolic load was measured per blood lactate concentration (BLaC), cognitive function per reaction time (RT), and neuromuscular performance including multiple rebound jumps (MRJ height, primary outcome variable; Reactive Strength Index, RSI) and 5 m sprint times (SP5).

RESULTS

Repeated-measures ANOVA revealed significant main time effects (p < .05) with improved performance post-exercise in RT (504 vs. 482 ms, d = 1.95), MRJ height (24.0 vs. 24.8 cm, d = 0.77), RSI (1.39 vs. 1.43, d = 0.52), and SP5 (1.19 vs. 1.17 s, d = 0.56). There was significant main time (p < .001) and time x protocol interaction effects in BLaC (p < .001). P1 induced higher BLaC values (4.52 ± 1.83 mmol/L) compared to P2 (3.79 ± 1.83 mmol/L; d = 0.74) and P4 (3.12 ± 1.83 mmol/L; d = 1.06), whereas P3 (4.23 ± 1.69 mmol/L) elicited higher BLaC values compared to P4 (d = 0.74).

CONCLUSION

All protocols caused an improved cognitive function and neuromuscular performance. The former may be related to enhanced noradrenergic activation or exercise specificity which induced an improved stimulus processing. The latter may be explained by a possible post-activation performance enhancement effect on jump and sprint performance. A shorter relief duration in W:R as opposed to sprint distance per interval produced higher BLaC values. The protocols may serve as reference data for improved RTS decision-making in elite female soccer players.

TRIAL REGISTRATION

Deutsches Register Klinischer Studien (DRKS), No.: DRKS00033496 , Registered 19. Februar 2024, Retrospectively Registered.

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.

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.

Practical Application and Methodological Considerations on the Basics of Sports Nutrition in Basketball: A Comprehensive Systematic Review of Observational and Interventional Studies

The current systematic review (PROSPERO registration no. CRD42022334707) of observational (OS) and interventional studies (IS) aimed at evaluating the state of scientific knowledge on the basics of sports nutrition, framing discipline-specific dietary recommendations, and indicating potential directions for future studies in various age, experience level, and able-bodied abilities groups of basketball players (BP). A systematic search of PubMed, SPORTDiscus, and Web of Science ended on 20 December 2022. Records were excluded if reporting studies on animals, sport disciplines other than basketball, or supplementation protocols other than those related to macronutrients and hydration manipulations. Risk of bias (RoB) was evaluated using Cochrane RoB_2 tools, 'JBI checklist for prevalence studies', and 'Quality assessment tool for before-after (pre-post) studies with no control group'. The relevant data was synthesized in tables and a narrative review was performed. Seventy-two records were included (2581 participants): 63 were on able-bodied BP (2433 participants) and 9 on para-athlete players (148 participants); 45 records were OS and 27 IS. The review disclosed widespread poor nutritional habits and knowledge and shortages in applying adequate nutritional and hydration practices in BP. Moreover, the systematic review revealed the lack of a sufficient number of investigations delivering reliable proof for framing discipline-specific and evidence-based recommendations on the basics of sports nutrition in basketball.

Room for Improvement in Sports Nutrition Knowledge amongst Parents and Caregivers of Male Academy Soccer Players in the UK: A Cross-Sectional Study

In professional soccer clubs in the UK, nutrition support is often polarised towards senior players or those in the senior academy age groups seeking first team selection/involvement. Accordingly, there is an increased reliance on parents and caregivers to provide support regarding nutritional intake. Therefore, the aim of this study was to evaluate the quality of nutrition knowledge of parents and caregivers of male youth soccer players within developmental academies in the UK. Across a single competitive season, 360 registered parents and caregivers of male soccer players from English Premier League under 9-11 (Foundation Phase) and under 12-16 (Youth Development Phase) age group academies completed an online version of the 88-item validated Nutrition for Sport Knowledge Questionnaire. Nutrition knowledge scores were classified as "poor" (43 ± 23%). Nutrition knowledge scores were significantly greater in respondents with dependents representing Category 1 (45 ± 13%) vs. Category 2 (39 ± 15%) academies and in Foundation Phase (44 ± 13%) vs. Youth Development Phase (41 ± 15%). These results demonstrate that there is room for improvement in the nutrition knowledge levels of parents and caregivers of male soccer academy players. We recommend that club academies provide appropriate resources towards nutritional education for parents and caregivers.

Designing New Sport Supplements Based on Aronia melanocarpa and Bee Pollen to Enhance Antioxidant Capacity and Nutritional Value

With a high number of athletes using sport supplements targeting different results, the need for complex, natural and effective formulations represents an actual reality, while nutrition dosing regimens aiming to sustain the health and performance of athletes are always challenging. In this context, the main goal of this study was to elaborate a novel and complex nutraceutical supplement based on multiple bioactive compounds extracted from Aronia melanocarpa and bee pollen, aiming to support physiological adaptations and to minimize the stress generated by intense physical activity in the case of professional or amateur athletes. Our proposed formulations are based on different combinations of Aronia and bee pollen (A1:P1, A1:P2 and A2:P1), offering personalized supplements designed to fulfill the individual requirements of different categories of athletes. The approximate composition, fatty acid profile, identification and quantification of individual polyphenols, along with the antioxidant capacity of raw biological materials and different formulations, was performed using spectrophotometric methods, GS-MS and HPLC-DAD-MS-ESI+. In terms of antioxidant capacity, our formulations based on different ratios of bee pollen and Aronia were able to act as complex and powerful antioxidant products, highlighted by the synergic or additional effect of the combinations. Overall, the most powerful synergism was obtained for the A1:P2 formulation.

The associations between anthropometric characteristics and nutritional parameters in male elite rugby union players

The objective was to analyse the associations between anthropometric characteristics and diet in male rugby players according to the playing position. A cross-sectional study was developed. The forwards had higher body weight (107 kg) and fat mass (FM; 12%) than the backs (87.8 kg and 8.47%, respectively) (p < 0.05). The quality of diet needs to improve (KIDMED value of 5.87 and 6.36 for forwards and backs, respectively). Nutritional imbalances, such as deficits in carbohydrates, fibre, calcium, magnesium and vitamin D, and excess of fats, saturated fatty acid, cholesterol and sugars were found. Carbohydrates and proteins intake were significant associated (p < 0.05) with a minor FM. Forwards with a KIDMED index of less than 8 had a significantly higher FM than those who maintained an optimal diet (p < 0.05). The diet of rugby players should be more in line with dietary recommendations and take into account the player position to optimise sports performance.

Assessment of the Dietary Intake and Nutritional Status of Polish Professional Futsal Players: A Descriptive Study-Do Futsal Players Require Nutritional Education?

Futsal is a discipline with high training and nutritional requirements. Despite growing research interest in athletes' diet and nutritional status, no studies have examined Polish male futsal players. Therefore, the aim of this descriptive study was an assessment of the dietary intake and nutritional status in a selected group of futsal players. The study comprised 11 members of a top Polish futsal team (aged 26 ± 3.62 years). Dietary intake was assessed using a standardized 3-day food record. Body composition, total energy expenditure, physical fitness level, and concentrations of the biochemical indices of each participant were estimated. The energy availability in the diet was lower than recommended. Moreover, low consumption of carbohydrates was stated, as well as an inadequate intake of Vitamins E and D. Higher protein and cholesterol intake than recommended were also observed. To conclude, our results point to the need for educating athletes and coaches, particularly teaching about proper food choices, promoting quality foods, and, in some cases, using individual dietary plans to meet energy and nutrient needs. Nutrition education would help to improve their dietary and health habits and optimize their performance in sports training.

The ergogenic effects of acute carbohydrate feeding on endurance performance: a systematic review, meta-analysis and meta-regression

A systematic review with meta-analysis was conducted to analyze the effect of carbohydrate (CHO) intake during exercise and some variables that could moderate this effect on endurance performance. We included 136 studies examining the effect of CHO ingestion during endurance exercise in the meta-analysis. The overall effect on performance showed a significant increase after CHO intake compared to the placebo/control groups. A larger effect of CHO consumption is observed in time to exhaustion than in time trials performance test. Moreover, the effectiveness of CHO supplementation was greater the longer the duration of the events. Also, there seems to be a higher effect of CHO intake in lower trained than in higher trained participants. In contrast, the magnitude of performance change of CHO intake is not affected by the dosage, ergometer used, the type of intake of the CHO ingestion and the type of CHO. In addition, a lower rate of perceived exertion and higher power and heart rate are significantly associated with the ingestion of CHO during endurance exercise. These results reinforce that acute CHO feeding is an effective strategy for improving endurance performance, especially, in less trained subjects participating in time to exhaustion tests of longer durations.

Personality Determinants of Exercise-Related Nutritional Behaviours among Polish Team Sport Athletes

A proper diet increases the effectiveness of training and accelerates post-workout regeneration. One of the factors determining eating behaviour are personality traits, including those included in the Big Five model, i.e., neuroticism, extraversion, openness, agreeableness, and conscientiousness. The aim of this study was to analyse the personality determinants of peri-exercise nutritional behaviours among an elite group of Polish athletes practicing team sports. The study was conducted in a group of 213 athletes, using the author's validated questionnaire of exercise-related nutrition behaviours and the NEO-PI-R (Neuroticism Extraversion Openness-Personality Inventory-Revised). A statistical analysis was performed using Pearson's linear correlation and Spearman's rank correlation coefficients as well as a multiple regression analysis, assuming a significance level of α = 0.05. It has been shown that the level of the overall index regarding normal peri-exercise eating behaviours decreased with increasing neuroticism (r = -0.18) and agreeableness (r = -0.18). An analysis of the relationship between the personality traits (sub-scales) of the Big Five model demonstrated that the overall index of proper peri-exercise nutrition decreased with the intensification of three neuroticism traits, i.e., hostility/anger (R = -0.20), impulsiveness/immoderation (R = -0.18), and vulnerability to stress/learned helplessness (R = -0.19), and four traits of agreeableness, i.e., straightforwardness/morality (R = -0.17), compliance/cooperation (R = -0.19), modesty (R = -0.14), and tendermindedness/sympathy (R = -0.15) (p < 0.05). A multiple regression analysis exhibited that the full model consisting of all the analysed personality traits explained 99% of the variance concerning the level of the proper peri-exercise nutrition index. In conclusion, the index of proper nutrition under conditions of physical effort decreases along with the intensification of neuroticism and agreeableness among Polish athletes professionally practicing team sports.

Energy availability and macronutrient intake in elite male Gaelic football players

Evidence suggests that Gaelic football (GF) players do not meet the recommended energy intake (EI) levels and therefore may be at risk of low energy availability (LEA). This study examined energy availability (EA) in 20 elite male GF players. At two stages during a season (2019-2020), repeated measures of EI, exercise energy expenditure (EEE), EA and body composition were performed. Sixty-five percent reported with LEA [<30 kcal.kg Lean Body Mass (LBM)^-1.day^-1] at pre-season (PRE), with 70% at in-season (IN). Mean daily carbohydrate intake (PRE 3.2 ± 0.82 g.kg; IN 3.4 ± 0.79 g.kg) was below the recommended intake (5-7 g.kg) in 95% at PRE and 100% at IN. All consumed the recommended daily amount of protein (PRE 1.85 ± 0.57 g.kg; IN 1.87 ± 0.48 g.kg) and fat (PRE 1.23 ± 0.4 g.kg; IN 1.02 ± 0.3 g.kg). Significant correlations (P = 0.001) were reported between EA and carbohydrates (PRE r = 0.801; IN r = 0.714); protein (PRE r = 0.675; IN r = 0.769); fat (PRE r = 0.805; IN r = 0.733) and energy intake (PRE r = 0.960; IN r = 0.949). Twenty percent were at risk of disordered eating. This study suggests male elite GF players require education and interventions surrounding nutrition, in particular EA.

Aspects Regarding the Consumption of Dietary Supplements among the Active Population in Romania

Food supplements contain a variety of combinations of vitamins, minerals, plant extracts, and other substances. Any physical effort requires energy from balanced and healthy nutrition. This research aimed to identify the categories of dietary supplements used by active and very active participants who attend the sports and leisure centers from Targu Mures city. The survey was developed in paper and online forms using the Internet and supported multimedia and self-administration. The sample consists of 517 subjects chosen randomly from the research population and divided into the active and highly active PAI subgroups based on age, education, and gender. IBM SPSS Statistics Version 20.0 was used to process the collected data. All data were analysed descriptively. Differences between independent groups were assessed using an Independent sample t-test and a Chi-square test. Statistical significance was accepted when p < 0.05. Additionally, a Pearson correlation was done. The most representative age category was between 18 and 22 years old (42.7%), the ones using dietary supplements most frequently. There were significant differences by group of age regarding the consumption of food supplements (p < 0.05) and also by gender (p < 0.05).

The Influence of Full-Time Holistic Support Delivered by a Sports Nutritionist on Within-Day Macronutrient Distribution in New Zealand Provincial Academy Rugby Union Players

Dietary intake is an important consideration for rugby union ('rugby') players to ensure substrate provision for optimal performance and facilitate recovery. Within-day meal distribution is especially important for athletes, particularly those with congested schedules and multiple daily training sessions. In the present study, 10 provincial academy rugby players engaged in a holistic support protocol informed by behaviour-change techniques led by a full-time sports nutritionist. Dietary intake was estimated during a 4-week monitoring and 4-week intervention period using the remote food photography method on one high-volume training day (two training sessions) and two low-volume training days (≤1 training session) per week. Lean body mass did not change significantly in response to the intervention. Significant increases were observed for protein on both low-volume (breakfast, AM snack, evening snack) and high-volume (post-gym, AM snack, evening snack) training days. Carbohydrate intake post-intervention was significantly greater at the pre-gym eating occasion but lower at PM snack and dinner eating occasions on high-volume days. These data suggest that incorporating a holistic support protocol led by a sports nutritionist can influence within-day nutrient intake in rugby players; however, no change to lean body mass was observed, and the influence of these changes in nutrient intake on performance and recovery warrants further investigation.

Practical Nutrition Strategies to Support Basketball Performance during International Short-Term Tournaments: A Narrative Review

A short-term (e.g., 6 days) basketball tournament is a shorter version of international tournaments, and qualification in it enables participation in international tournaments such as the Olympics and World championships or preparation before major tournaments. Time for recovery between matches is shorter compared with major tournaments, resulting in an accentuated load on players, which can be repeated up to four times within the 6-day competition period. Therefore, nutritional strategies need to focus on faster and adequate recovery after each match as well as optimum fuelling and hydration before and during matches. Travelling can also create additional challenges when preparing and/or applying those nutritional strategies. There are some particular evidence-based sport foods and ergogenic aids that can improve intermittent activity and/or the execution of motor skills, which may facilitate basketball players' recovery and performance. The present review provides practical nutritional strategies to support short-term basketball tournaments based on players' physiological needs and current sport nutrition guidelines.

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

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

Dietary Intake of Recreational Endurance Runners Associated with Race Distance-Results from the NURMI Study (Step 2)

While the popularity of distance running is growing worldwide, endurance runners’ dietary challenges associated with their prolonged training and racing activities have not yet been fully understood. The present investigation was conducted with the aim of examining the association between race distance and dietary intake of distance runners. A total of 317 runners initially participated, and after data clearance, 211 endurance runners (57% females) were finally considered the study sample. Runners were assigned to three race distance groups: 10-km (n = 74), half-marathon (n = 83), and marathon/ultra-marathon (n = 54). An online survey was used to collect data; dietary intake was monitored using a comprehensive food frequency questionnaire, including 53 food groups categorized in 14 basic and three umbrella clusters. There was no significant difference (p > 0.05) between race distance groups in consumption of most food clusters except for “fruits and vegetables” and “total of protein”, with a predominance of 10-km runners compared to half-marathoners and (ultra-)marathoners (p ≤ 0.05). Age was a significant predictor for the consumption of only five (out of 17) food clusters (p ≤ 0.05), including “fruit and vegetables”, “unprocessed meat”, “processed meat”, “eggs”, and “plant protein”. Future investigations with a larger sample size and more differentiated (sub)groups may help provide comparable data to develop a better understanding of the dietary behaviors among shorter versus longer distance runners.

Factors influencing performance and injury risk in elite female Gaelic team sport players and future research directions: a narrative review

BACKGROUND

Sports science research in elite female Gaelic team sports has increased in recent years, but still a large disparity exists between the volume of studies involving male and female players. As a consequence of this, it is difficult for practitioners to develop an evidence-based approach when working with female players.

MAIN BODY

In this review, we discuss the current research available in elite female Gaelic team sports with focus on seven specific areas including physical and physiological demands, anthropometric and performance characteristics, injury risk, nutritional considerations, and female physiology. There appears to be unique physical demands data in match play across positions in Camogie, however, there is currently no comparative data available in ladies Gaelic football. Similarly, there is no research available on the physiological demands of both elite female Gaelic team sports. According to existing literature, performance characteristics such as speed and power are lower in this population compared to other elite female team sports. Although data is limited, the anthropometric characteristics of elite female Gaelic team sport players appear homogenous with some positional differences observed at a sub-elite level. Previous research has demonstrated a high prevalence of lower limb injuries in female elite Gaelic team sports and the provision of quality, evidence-based strength & conditioning could help mitigate these injury risks. Female Gaelic team sport players have been shown to have poor nutrition knowledge and inadequate intakes of micronutrients. Finally, although menstrual cycle phase and oral contraceptives have been shown to influence performance in other female intermittent sports, to date there has not been any research carried out in elite female Gaelic team sport players.

CONCLUSIONS

It is evident that limited research has been carried out on elite female Gaelic sport players. More up-to-date, high-quality investigations are needed to address the research gaps, which in turn should enable practitioners in the field to apply sound, evidence-based practice/theory when working with this population.

Assessing Dietary Nutrient Adequacy and the Effect of Season-Long Training on Body Composition and Metabolic Rate in Collegiate Male Basketball Players

The success of performance in basketball relies on both optimal body composition and nutrient intake. The purpose of this study was to examine seasonal changes in body composition (BC), resting metabolic rate (RMR) and respiratory quotient (RQ), as well as dietary intake of National Collegiate Athletic Association (NCAA) Division I (DI) male basketball players. BC, RMR and RQ were assessed during pre-season, in-season, and post-season (September, December, and March) while dietary assessment data were collected in September and February. Results of this study indicated that players received inadequate energy (p < 0.0001), protein (p < 0.001) and carbohydrate (p < 0.0001) relative to the recommendations for exercising individuals during the September baseline period. However, following diet analysis and consultations and relative to recommendations, athletes received adequate amounts of energy and protein during follow-up, yet intakes of carbohydrate (p = 0.0025) were still significantly different than recommended. Results also indicated that there was a decrease in percent body fat (%BF) during season, an increase in lean body mass (LBM) from pre- to post-season, a peak in RMR during season and an increase in RQ post-season. These findings reveal that significant metabolic and body composition changes occur in players over the season and suggest that nutritional strategies employed concomitantly may be beneficial.

Fluid Balance and Carbohydrate Intake of Elite Female Soccer Players during Training and Competition

This study examined sweat rate, sweat sodium concentration [Na⁺], and ad-libitum carbohydrate and fluid intakes in elite female soccer players during training (n = 19) and a match (n = 8); eight completed both for comparisons. Body mass (kg) was obtained before and after exercise to calculate sweat rate. The sweat [Na⁺] was determined from absorbent patches on the thigh or back. Sweat rate, percentage body mass change, and sweat [Na⁺] for 19 players during training were 0.47 ± 0.19 L·h⁻¹, +0.19 ± 0.65%, and 28 ± 10 mmol·L⁻¹, respectively. Sweat rate was higher during a match (0.98 ± 0.34 L·h⁻¹) versus training (0.49 ± 0.26 L·h⁻¹, p = 0.007). Body mass losses were greater post-match (−1.12 ± 0.86%) than training (+0.29 ± 0.34%, p = 0.003). Sweat [Na⁺] was similar for training (29 ± 9 mmol·L⁻¹) and a match (35 ± 9 mmol·L⁻¹) (p = 0.215). There were no differences in match versus training carbohydrate intakes (2.0 ± 2.3 g·h⁻¹, 0.9 ± 1.5 g·h⁻¹, respectively, p = 0.219) or fluid intakes (0.71 ± 0.30 L·h⁻¹, 0.53 ± 0.21 L·h⁻¹, respectively, p = 0.114). In conclusion, female soccer players’ sweat rates were higher during a match than during training, and carbohydrate intakes were below recommendations for matches and training.

Effects of the ketogenic diet on performance and body composition in athletes and trained adults: a systematic review and Bayesian multivariate multilevel meta-analysis and meta-regression

This systematic review with meta-analysis aimed to determine the effects of the ketogenic diet (KD) against carbohydrate (CHO)-rich diets on physical performance and body composition in trained individuals. The MEDLINE, EMBASE, CINAHL, SPORTDiscus, and The Cochrane Library were searched. Randomized and non-randomized controlled trials in athletes/trained adults were included. Meta-analytic models were carried out using Bayesian multilevel models. Eighteen studies were included providing estimates on cyclic exercise modes and strength one-maximum repetition (1-RM) performances and for total, fat, and free-fat masses. There were more favorable effects for CHO-rich than KD on time-trial performance (mode [95% credible interval]; -3.3% [-8.5%, 1.7%]), 1-RM (-5.7% [-14.9%, 2.6%]), and free-fat mass (-0.8 [-3.4, 1.9] kg); effects were more favorable to KD on total (-2.4 [-6.2, 1.8] kg) and fat mass losses (-2.4 [-5.4, 0.2] kg). Likely modifying effects on cyclic performance were the subject's sex and VO2max, intervention and performance durations, and mode of exercise. The intervention duration and subjects' sex were likely to modify effects on total body mass. KD can be a useful strategy for total and fat body losses, but a small negative effect on free-fat mass was observed. KD was not suitable for enhancing strength 1-RM or high-intensity cyclic performances.

Nutritional Intake and Training Load of Professional Female Football Players during a Mid-Season Microcycle

Football (soccer) is a high-intensity intermittent sport with large energy demands. In a repeated-measures design, we analysed the nutritional intake and training load of fourteen female football players (22.50 ± 4.38 y; 57.23 ± 8.61 kg; 164 ± 6.00 cm; 18.33 ± 2.48% of fat mass and 23.71 ± 2.51 kg of muscle mass) competing in the highest female Football Portuguese League across a typical mid-season microcycle. The microcycle had one match day (MD), one recovery session (two days after the MD, MD+2), three training sessions (MD-3, MD-2, MD-1) and two rest days (MD+1). Energy intake and CHO (g.kg.BW−1) intake were lower on the days before the competition (MD+2, MD-3, MD-2 and MD-1 vs. MD; p < 0.05; ES: 0.60−1.30). Total distance, distance covered at high-speed running (HSRD) and the high metabolic distance load (HMLD) were lower on MD+2, MD-3 and MD-1 compared with MD (p < 0.05; ES: <0.2−5.70). The internal training load was lower in all training sessions before the competition (MD+2, MD-3, MD-2 and MD-1 vs. MD; p ≤ 0.01; ES: 1.28−5.47). Despite the small sample size and a single assessment in time, the results suggest that caloric and CHO intake were below the recommendations and were not structured based on the physical requirements for training sessions or match days.

A Multidisciplinary Approach to Game Day Preparation for Team Sports: A Delphi Study With Expert Consensus

ABSTRACT

Mason, BRJ, Pumpa, KL, McKune, AJ, Gill, ND, and Ball, NB. A multidisciplinary approach to game day preparation for team sports: A Delphi study with expert consensus. J Strength Cond Res 36(5): 1345-1352, 2022-The aim of this study was to identify game day preparation strategies used by performance staff to improve team sport performance and to determine consensus regarding the application and importance of these strategies. Twenty-five performance staff working in high performance or professional team sports participated in this Delphi study, which implemented 3 survey rounds. The first round sought responses to open-ended questions relating to the use of game day preparation strategies. These responses were developed into statements and recirculated (round-2 survey), with subjects asked to rate their level of agreement with each statement. The third and final survey presented revised versions of statements that did not reach a consensus in the previous round, along with new statements derived from subject responses. A thematic analysis of the open-ended responses in the first survey identified 5 key themes relating to game day preparation strategies: "exercise," "nutrition," "psychological," "technical and tactical," and "other." The round-2 survey included 38 statements across the 5 themes, with 22 reaching the consensus threshold (≥75%) for agreement. The remaining 16 statements did not reach consensus. The final survey included 18 statements (16 revised and 2 new) with 12 reaching the consensus threshold for agreement. Key preparation strategies identified in this study include structured and progressive warm-ups, strength and power-based priming sessions, individualized nutrition plans, and precooling in hot conditions. Performance staff working in similar environments should consider adopting these strategies to improve athlete or team performance.

Nutrition knowledge of elite and non-elite Gaelic footballers

Dietary intake plays a significant role in athletic performance and is influenced by several factors, including nutrition knowledge. Gaelic footballers are amateur athletes who conduct high-intensity, intermittent activity during training and competition, and have previously demonstrated insufficient dietary intake. This study aimed to examine nutrition knowledge in elite and non-elite Gaelic footballers. An online survey was distributed to competitive Gaelic footballers, examining nutrition knowledge using the Abridged Nutrition for Sport Knowledge Questionnaire. Total, general, and sport nutrition knowledge were compared between elite and non-elite athletes, and those who had and had not previously received nutrition education, using Mann-Whitney U-tests. A total of 190 participants (15.3% women) completed the survey. No differences between elite and non-elite athletes in nutrition knowledge were identified (p > 0.05). Athletes with previous nutrition education scored higher than those without previous nutrition education in total (54.0 ± 4.9% vs 46.8 ± 9.6%; p = 0.002) and sport (51.9 ± 12.5% vs 43.4 ± 11.8%; p = 0.005) nutrition knowledge. Findings suggest an importance of nutrition education at all levels of athletic competition to improve nutrition knowledge, which may empower athletes to make appropriate dietary decisions to support training and competition demands.

New Opportunities to Advance the Field of Sports Nutrition

Sports nutrition is a relatively new discipline; with ~100 published papers/year in the 1990s to ~3,500+ papers/year today. Historically, sports nutrition research was primarily initiated by university-based exercise physiologists who developed new methodologies that could be impacted by nutrition interventions (e.g., carbohydrate/fat oxidation by whole body calorimetry and muscle glycogen by muscle biopsies). Application of these methods in seminal studies helped develop current sports nutrition guidelines as compiled in several expert consensus statements. Despite this wealth of knowledge, a limitation of the current evidence is the lack of appropriate intervention studies (e.g., randomized controlled clinical trials) in elite athlete populations that are ecologically valid (e.g., in real-life training and competition settings). Over the last decade, there has been an explosion of sports science technologies, methodologies, and innovations. Some of these recent advances are field-based, thus, providing the opportunity to accelerate the application of ecologically valid personalized sports nutrition interventions. Conversely, the acceleration of novel technologies and commercial solutions, especially in the field of biotechnology and software/app development, has far outstripped the scientific communities' ability to validate the effectiveness and utility of the vast majority of these new commercial technologies. This mini-review will highlight historical and present innovations with particular focus on technological innovations in sports nutrition that are expected to advance the field into the future. Indeed, the development and sharing of more “big data,” integrating field-based measurements, resulting in more ecologically valid evidence for efficacy and personalized prescriptions, are all future key opportunities to further advance the field of sports nutrition.

Carbohydrate Mouth-Rinsing Improves Overtime Physical Performance in Male Ice Hockey Players During On-Ice Scrimmages

Purpose

This randomized, double-blind, crossover study examined the effects of mouth-rinsing (MR) with a carbohydrate (CHO) vs. a placebo (PLA) solution on external and internal loads in hydrated ice hockey players during regulation and overtime (OT) periods of an on-ice scrimmage.

Methods

Twelve skilled male hockey players (22.6 [3.4] years, 178.9 [4.7] cm, 84.0 [6.5] kg) played three 20-min regulation periods and one 12-min OT period of small-sided 3-on-3 scrimmage. Skaters repeated 2 min shift and rest intervals. Participants mouth rinsed with 25 mL of CHO or PLA solution approximately every 10 min for a total of 7 rinses. A local positioning system (LPS) tracked external load variables including speed, distance, acceleration, and deceleration. Internal load was monitored with heart rate (HR) sensors and a rating of perceived exertion (RPE).

Results

During regulation play, both the conditions developed similar fatigue, with significantly decreased high-intensity distance, average speed and decelerations, and increased RPE, from period 1 to 2 and 3. In OT, CHO MR increased the distance skated at high-intensity (224 [77], 185 [66] m, p = 0.042), peak speed (24.6 [1.6], 23.7 [1.3] km·h⁻¹, p = 0.016), number of sprints (1.9 [1.2], 1.2 [0.9], p = 0.011), and decreased distance skated at slow speed (300 [33], 336 [47], p = 0.034) vs. PLA MR. OT RPE was similar between the two conditions in spite of more work done in CHO MR.

Conclusions

CHO MR may be a valuable practice to protect against decrements in external load with increased playing time in ice hockey, and possibly allows athletes to perform more work relative to perceived levels of exertion.

Ergo-Nutritional Intervention in Basketball: A Systematic Review

Using nutritional supplements is a widespread strategy among basketball players to ensure the appropriate provision of energy and nutrients to avoid certain complaints. Particularly in basketball, there is no consensus on the type, quantity or form of use in which these supplements should be administered. Therefore, the main aim of this systematic review is to highlight the ergo-nutritional aids that may be effective in basketball. A structured search was carried out following the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA®) guidelines in the Medline/PubMed and Web of Science, Cochrane Library, and Scopus databases until 31 December 2021; no year restriction was applied to the search strategy. There were no filters applied to the basketball players' level, gender, race, or age to increase the power of the analysis. The results of this systematic review have shown that the effective dose of caffeine to enhance anaerobic performance and the feeling of vigorousness and energy ranges from 3 to 6 mg·kg-1, showing more positive effects when is supplemented 60-75 min before exercise in the morning and in test-based task. On the other hand, vitamin E (ranging from 200 to 268 mg), vitamin D (10,000 IU) and EPA (2 g) may have a potential role in recovery and wellness. The primary limitation of this study is the scarcity of studies related to nutritional supplementation in basketball players. However, a major strength is that this is the first systematic review describing what ergo-nutritional aids may be specifically helpful for basketball. Despite the need for future studies, certain nutritional supplements may have promising advantages for basketball (long-term supplementation of nitrates for recovery), whereas others (β-alanine, sodium bicarbonate, and acute nitrate supplementation) might theoretically be regarded as not interesting for basketball, or even not recommended by the World Anti-Doping Agency (WADA) as bovine colostrum.

New electrolyte beverages prepared by the citrus canning processing water through chemical improvement

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Citrus segment membrane removal during canning was improved for clean process.

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The improved process using mixed acid (alkali) showed good membrane removal result.

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The processing water was fully used for preparing a new healthy electrolyte drink.

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The bioactive compounds in the canning processing water were completely recoverd.

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This green process with economic viability has great society benefits.

In the production of canned citrus, large amounts of processing water were discharged during the segment membrane removal process, causing severe pollution. In order to reduce pollution and recover the bioactive compounds in the processing water, the production of canned satsuma mandarin, sweet orange and grapefruit were studied, and improved acid (0.1% HCl, 0.4% citric acid) and alkali (0.1% KOH, 0.2% NaOH) were used to conduct the new chemical hydrolysis process to remove the segment membrane. The obtained acid and alkali processing water were firstly explored the potential to make novel beverages, which contain electrolytes (Na: 472–945 ppm; K: 208–279 ppm; Cl: 364–411 ppm; citrate: 1105–1653 ppm) and potential prebiotics such as pectin and flavonoids. The improved segment membrane removal process realized the conversion of wastewater into drinkable beverages at low costs. The bioactive compounds were fully recovered without wastewater discharging, which produced great environmental, economic and health value.

A Glimpse of the Sports Nutrition Awareness in Spanish Basketball Players

Basketball is a team sport, with many fans and practitioners worldwide from all ages and levels. In all cases, players accumulate high levels of fatigue, and there is also limited time to recover between games or practices. In particular, nutrition plays a key role in optimizing performance and recovery. However, it is typical to observe erroneous nutritional behaviors among basketball players. It has been theorized that these behaviors are influenced by habits acquired based on the individual’s knowledge. Therefore, the main aim of this study was to conduct a descriptive research of the sports nutrition knowledge and practices in a sample of Spanish basketball players, from athletes under 18 years old (n = 69) to nonprofessional (n = 14) and professional adult players (n = 21). The sample was comprised of 49 men and 55 women. This was a transversal, cross-sectional, observational and descriptive study. All participants (n = 104) completed an anonymous online survey in order to analyze their sports nutrition knowledge and practices. In view of the obtained results, we can conclude that the knowledge of sport-specific nutrition in players under 18 years old, as well as non-professional and professional adult basketball players, is insufficient through all the categories and levels. The lack of professional support and time management difficulties were identified as some of the main barriers.

In-Season Nutrition Strategies and Recovery Modalities to Enhance Recovery for Basketball Players: A Narrative Review

Basketball players face multiple challenges to in-season recovery. The purpose of this article is to review the literature on recovery modalities and nutritional strategies for basketball players and practical applications that can be incorporated throughout the season at various levels of competition. Sleep, protein, carbohydrate, and fluids should be the foundational components emphasized throughout the season for home and away games to promote recovery. Travel, whether by air or bus, poses nutritional and sleep challenges, therefore teams should be strategic about packing snacks and fluid options while on the road. Practitioners should also plan for meals at hotels and during air travel for their players. Basketball players should aim for a minimum of 8 h of sleep per night and be encouraged to get extra sleep during congested schedules since back-to back games, high workloads, and travel may negatively influence night-time sleep. Regular sleep monitoring, education, and feedback may aid in optimizing sleep in basketball players. In addition, incorporating consistent training times may be beneficial to reduce bed and wake time variability. Hydrotherapy, compression garments, and massage may also provide an effective recovery modality to incorporate post-competition. Future research, however, is warranted to understand the influence these modalities have on enhancing recovery in basketball players. Overall, a strategic well-rounded approach, encompassing both nutrition and recovery modality strategies, should be carefully considered and implemented with teams to support basketball players' recovery for training and competition throughout the season.

Meta-Analysis of Carbohydrate Solution Intake during Prolonged Exercise in Adults: From the Last 45+ Years' Perspective

Carbohydrate (CHO) supplementation during prolonged exercise postpones fatigue. However, the optimum administration timing, dosage, type of CHO intake, and possible interaction of the ergogenic effect with athletes' cardiorespiratory fitness (CRF) are not clear. Ninety-six studies (from relevant databases based on predefined eligibility criteria) were selected for meta-analysis to investigate the acute effect of ≤20% CHO solutions on prolonged exercise performance. The between-subject standardized mean difference [SMD = ([mean post-value treatment group-mean post-value control group]/pooled variance)] was assessed. Overall, SMD [95% CI] of 0.43 [0.35, 0.51] was significant (p < 0.001). Subgroup analysis showed that SMD was reduced as the subjects' CRF level increased, with a 6-8% CHO solution composed of GL:FRU improving performance (exercise: 1-4 h); administration during the event led to a superior performance compared to administration before the exercise, with a 6-8% single-source CHO solution increasing performance in intermittent and 'stop and start' sports and an ~6% CHO solution appearing beneficial for 45-60 min exercises, but there were no significant differences between subjects' gender and age groups, varied CHO concentrations, doses, or types in the effect measurement. The evidence found was sound enough to support the hypothesis that CHO solutions, when ingested during endurance exercise, have ergogenic action and a possible crossover interaction with the subject's CRF.

Nutritional approaches to counter performance constraints in high-level sports competition

New Findings

What is the topic of this review?

The nutritional strategies that athletes use during competition events to optimize performance and the reasons they use them.

What advances does it highlight?

A range of nutritional strategies can be used by competitive athletes, alone or in combination, to address various event‐specific factors that constrain event performance. Evidence for such practices is constantly evolving but must be combined with understanding of the complexities of real‐life sport for optimal implementation.

Abstract

High‐performance athletes share a common goal despite the unique nature of their sport: to pace or manage their performance to achieve the highest sustainable outputs over the duration of the event. Periodic or sustained decline in the optimal performance of event tasks, involves an interplay between central and peripheral phenomena that can often be reduced or delayed in onset by nutritional strategies. Contemporary nutrition practices undertaken before, during or between events include strategies to ensure the availability of limited muscle fuel stores. This includes creatine supplementation to increase muscle phosphocreatine content and consideration of the type, amount and timing of dietary carbohydrate intake to optimize muscle and liver glycogen stores or to provide additional exogenous substrate. Although there is interest in ketogenic low‐carbohydrate high‐fat diets and exogenous ketone supplements to provide alternative fuels to spare muscle carbohydrate use, present evidence suggests a limited utility of these strategies. Mouth sensing of a range of food tastants (e.g., carbohydrate, quinine, menthol, caffeine, fluid, acetic acid) may provide a central nervous system derived boost to sports performance. Finally, despite decades of research on hypohydration and exercise capacity, there is still contention around their effect on sports performance and the best guidance around hydration for sporting events. A unifying model proposes that some scenarios require personalized fluid plans while others might be managed by an ad hoc approach (ad libitum or thirst‐driven drinking) to fluid intake.

The Personal Food Systems of Pre-Season NCAA Division 1 High-Contact, Low-Contact, and Non-Contact College Athletes

Previous research indicates that dietary habits may differ between athletes of different sports. In this cross-sectional study, we hypothesize meal frequency, food choices, and food preferences will significantly differ between contact types. The participants were athletes (n = 92; men: n = 57, body fat percent (BF%): 14.8 ± 8.4%, body mass index (BMI): 25.5 ± 5.5 kg·m^-2; women: n = 36, BF%: 26.7 ± 7.3%, BMI: 22.3 ± 2.7 kg·m^-2) from high-contact (HCS), low-contact (LCS), and non-contact (NCS) sports. Meal frequency, food preference, and food choice questionnaires assessed factors influencing dietary habits. Dual-energy X-ray absorptiometry (DXA) measured lean body mass, fat mass, and body fat. A GLM multivariate analysis was used with significance accepted at p < 0.05. Significant body composition differences were observed between genders (p < 0.001) and among sports (p < 0.001). Dinner (83.7%), lunch (67.4%), and breakfast (55.4%) were the most frequently eaten meals, followed by evening snack (17.8%), afternoon snack (15.2%), and morning snack (8.7%). Greater preferences for starches were observed for HCS (p = 0.04; η² = 0.07) and for a greater preference for vegetables was found for NCS (p = 0.02; η² = 0.09). Significant differences also existed in the importance of health (p = 0.04; η² = 0.07), weight control (p = 0.05; η² = 0.11), natural content (p = 0.04; η² = 0.07), and price (p = 0.04; η² = 0.07). These results support our hypothesis that food choices and food preferences differ between contact types. This may help sports dieticians create more individualized nutrition programs.

Achieving an Optimal Fat Loss Phase in Resistance-Trained Athletes: A Narrative Review

Managing the body composition of athletes is a common practice in the field of sports nutrition. The loss of body weight (BW) in resistance-trained athletes is mainly conducted for aesthetic reasons (bodybuilding) or performance (powerlifting or weightlifting). The aim of this review is to provide dietary–nutritional strategies for the loss of fat mass in resistance-trained athletes. During the weight loss phase, the goal is to reduce the fat mass by maximizing the retention of fat-free mass. In this narrative review, the scientific literature is evaluated, and dietary–nutritional and supplementation recommendations for the weight loss phase of resistance-trained athletes are provided. Caloric intake should be set based on a target BW loss of 0.5–1.0%/week to maximize fat-free mass retention. Protein intake (2.2–3.0 g/kgBW/day) should be distributed throughout the day (3–6 meals), ensuring in each meal an adequate amount of protein (0.40–0.55 g/kgBW/meal) and including a meal within 2–3 h before and after training. Carbohydrate intake should be adapted to the level of activity of the athlete in order to training performance (2–5 g/kgBW/day). Caffeine (3–6 mg/kgBW/day) and creatine monohydrate (3–5 g/day) could be incorporated into the athlete’s diet due to their ergogenic effects in relation to resistance training. The intake of micronutrients complexes should be limited to special situations in which there is a real deficiency, and the athlete cannot consume through their diet.

Portuguese Football Federation consensus statement 2020: nutrition and performance in football

Nutrition is an undeniable part of promoting health and performance among football (soccer) players. Nevertheless, nutritional strategies adopted in elite football can vary significantly depending on culture, habit and practical constraints and might not always be supported by scientific evidence. Therefore, a group of 28 Portuguese experts on sports nutrition, sports science and sports medicine sought to discuss current practices in the elite football landscape and review the existing evidence on nutritional strategies to be applied when supporting football players. Starting from understanding football's physical and physiological demands, five different moments were identified: preparing to play, match-day, recovery after matches, between matches and during injury or rehabilitation periods. When applicable, specificities of nutritional support to young athletes and female players were also addressed. The result is a set of practical recommendations that gathered consensus among involved experts, highlighting carbohydrates periodisation, hydration and conscious use of dietary supplements.