Abbie E Smith-Ryan, Gabrielle M DelBiondo, Ann F Brown, Susan M Kleiner, Nhi T Tran, Stacey J Ellery
{"title":"Creatine in women's health: bridging the gap from menstruation through pregnancy to menopause.","authors":"Abbie E Smith-Ryan, Gabrielle M DelBiondo, Ann F Brown, Susan M Kleiner, Nhi T Tran, Stacey J Ellery","doi":"10.1080/15502783.2025.2502094","DOIUrl":"10.1080/15502783.2025.2502094","url":null,"abstract":"<p><strong>Background: </strong>Creatine supplementation in women has gained attention for its potential benefits beyond muscle growth, including reproductive health, cognitive health and aging. Women exhibit distinct physiological differences from men, influenced by hormonal fluctuations during pre-menopause, pregnancy, and menopause, and these factors should be considered for their influence on creatine metabolism.</p><p><strong>Objective: </strong>This review aims to provide a historical evaluation of creatine supplementation in women, its potential applications across female-specific life stages, recent research highlights, and targets for future research. The review also considers the impact of hormonal changes on creatine metabolism and effectiveness as a dietary supplementation.</p><p><strong>Methods: </strong>This is a narrative overview of historical and recent research evaluating the effects of creatine in women.</p><p><strong>Results: </strong>Early studies demonstrated the benefits of creatine on exercise performance in women, though they often overlooked menstrual cycle variability. Recent research has begun to account for these hormonal fluctuations, enhancing the understanding of creatine's applications. Creatine supplementation has shown positive effects on muscle strength, exercise performance, and body composition, particularly when combined with resistance training. Additionally, creatine may improve mood and cognitive function, potentially alleviating symptoms of depression. Emerging evidence suggests creatine's benefits during pregnancy and post-menopause, though data on perimenopausal women remains limited.</p><p><strong>Conclusion: </strong>Creatine supplementation presents a promising strategy for enhancing various aspects of women's health across the lifespan. Future research should focus on optimizing dosing strategies, understanding long-term health implications, and exploring creatine's effects during pregnancy and perimenopause.</p>","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"22 1","pages":"2502094"},"PeriodicalIF":4.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12086928/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144078885","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
David Marko, Ronald L Snarr, Petr Bahenský, Václav Bunc, Miroslav Krajcigr, Tomáš Malý
{"title":"Beta-alanine supplementation improves time to exhaustion, but not aerobic capacity, in competitive middle- and long-distance runners.","authors":"David Marko, Ronald L Snarr, Petr Bahenský, Václav Bunc, Miroslav Krajcigr, Tomáš Malý","doi":"10.1080/15502783.2025.2521336","DOIUrl":"10.1080/15502783.2025.2521336","url":null,"abstract":"<p><strong>Background: </strong>Beta-alanine (βA) is a non-essential amino acid purportedly used to enhance aerobic exercise performance. While previous research indicates the benefits of βA on time to exhaustion (TTE) and aerobic capacity (VO<sub>2peak</sub>) in adults, evidence is lacking in adolescent athletes. Thus, the purpose of this study was to determine the effects of 4 weeks of βA supplementation on aerobic performance in adolescent runners.</p><p><strong>Methods: </strong>Twenty-seven middle- and long-distance runners (aged 17.36 ± 2.17 years) were randomly divided into a βA or placebo (PL) group (maltodextrin). Subjects performed maximal graded exercise tests (GXT) and submaximal trials (SMT; 80% of VO<sub>2peak</sub> for 1500 m) on a treadmill before and after 14 and 28 days of supplementation or PL. Respiratory (V<sub>E</sub>) metabolic (VO<sub>2</sub>, RER, lactate [La]), and cardiovascular (HR) variables were measured during the GXT and SMT, along with the first (VT1) and second ventilatory threshold (VT2) and TTE monitored during the GXT only. Within- and between-group differences were assessed using a repeated-measures mixed-model analysis of variance.</p><p><strong>Results: </strong>Findings indicated that despite a trivial increase in VO<sub>2peak</sub> over 4 weeks, the βA group increased TTE by 6.5% compared to 1.4% in the PL group (<i>d</i> = 0.46). Additionally, small effects in HR<sub>max</sub>, V<sub>E</sub>, [La], and TTE were observed between groups favoring βA. Regarding the SMT, both average HR and RER decreased by 4% in the βA group, with no changes for the PL.</p><p><strong>Conclusions: </strong>Despite no evidence to suggest increases in VO<sub>2peak</sub>, practitioners should note that improvements in TTE may be observed after 28 days of βA supplementation in adolescent runners.</p>","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"22 1","pages":"2521336"},"PeriodicalIF":4.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12175181/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144317219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ranil Jayawardena, Kalani Weerasinghe, Indu Nanayakkara, Terrence Madhujith, Andrew P Hills, Nishan Sudheera Kalupahana
{"title":"Improvement of sports nutrition knowledge by a dual method education program in track and field athletes: a randomized controlled trial.","authors":"Ranil Jayawardena, Kalani Weerasinghe, Indu Nanayakkara, Terrence Madhujith, Andrew P Hills, Nishan Sudheera Kalupahana","doi":"10.1080/15502783.2025.2519517","DOIUrl":"10.1080/15502783.2025.2519517","url":null,"abstract":"<p><strong>Background: </strong>Athletes with strong sports nutrition knowledge are believed to have sound nutritional practices and better performance. This study aimed to evaluate the effectiveness of a dual-method personalized nutrition education program in improving sports nutrition knowledge (SNK) among Sri Lankan track and field athletes.</p><p><strong>Methods: </strong>This parallel-group, randomized controlled trial recruited national-level track and field athletes aged 18 and above. The intervention group (IG) received personalized sports nutrition consultations at 0, 4<sup>th</sup>, and 8<sup>th</sup> weeks, along with online educational materials via WhatsApp from weeks 10 to 16, while the control group (CG) did not receive any intervention. A per-protocol analysis was followed, and t-tests were used to compare the means.</p><p><strong>Results: </strong>Of the 30 participants enrolled, 13 from IG and 14 from CG completed the study. Following the 16-week intervention, the IG demonstrated significant improvements in total nutrition knowledge (TNK) relative to the CG (IG: 34.41 ± 4.15 vs. CG: 20.96 ± 4.38; <i>p</i> = 0.01), with significant increases in general nutrition knowledge (GNK) (IG:24.54 ± 3.66 vs. CG:15.64 ± 2.33; <i>p</i> = 0.004) and SNK (9.87 ± 3.87 vs. 5.32 ± 4.07; <i>p</i> = 0.006). Changes in TNK were also significantly greater in the IG compared to the CG; (IG:9.45 ± 0.10 vs. CG: -2.63 ± 0.37; <i>p</i> < 0.0001), GNK (IG:4.47 ± 0.08 vs. CG: -1.28 ± 0.09; <i>p</i> < 0.0001), and SNK (IG:4.99 ± 0.72 vs. CG: -1.25 ± 0.74; <i>p</i> < 0.0001).</p><p><strong>Conclusions: </strong>The 16-week dual-method nutrition education intervention was effective in improving TNK, GNK, and SNK among track and field athletes in Sri Lanka.</p><p><strong>Trial registration: </strong>This trial is registered at the Sri Lanka Clinical Trials Registry (SLCTR/2024/013), Universal Trial Number (UTN): U1111-1304-8890 on 10 April 2024.</p>","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"22 1","pages":"2519517"},"PeriodicalIF":4.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12175182/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144310093","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Effect of different sports drink compositions on endurance performance and substrate oxidation: a randomized, double-blind, placebo-controlled crossover study in trained athletes.","authors":"Sascha Ketelhut, Martin Moehle, Laura Hottenrott","doi":"10.1080/15502783.2025.2516004","DOIUrl":"10.1080/15502783.2025.2516004","url":null,"abstract":"<p><strong>Background: </strong>The consumption of sports drinks before, during, and after endurance exercise is a common practice among athletes. These drinks typically contain a variety of components, each of which has been shown to offer individual benefits. However, the combined effects of these components, as formulated in many sports drinks, have not been thoroughly investigated. This study aims to evaluate the impact of typical sports drink components on endurance performance, perceived exertion, and carbohydrate and fat metabolism, using a sequential additive design.</p><p><strong>Methods: </strong>Twelve healthy, trained endurance athletes aged 20 to 35 years participated in a randomized, double-blind, placebo-controlled study. The study involved a baseline assessment and four exercise protocols, each separated by a 7-day washout period. During each exercise protocol, participants cycled for 40 minutes at 80% of their previously determined peak oxygen uptake , followed by an incremental protocol performed to voluntary exhaustion. Participants were randomly assigned to ingest one of four 300 ml solutions 60 and 30 minutes before each exercise protocol: solution A (placebo mineral water), solution B (dextrose and sodium), solution C (solution B + beetroot extract), or solution D (solution C + arginine and L-citrulline). Ventilation and heart rate were continuously monitored before and throughout the exercise. Lactate and glucose levels were measured at specific time points before and during the exercise, while ratings of perceived exertion were recorded every 10 minutes. Power output was continuously tracked throughout the exercise protocol. Body weight was assessed both before and after each exercise session.</p><p><strong>Results: </strong>There were no significant differences between the four solutions in terms of time to exhaustion (<i>p</i> = .703), power output (<i>p</i> = .822), peak oxygen uptake (<i>p</i> = 990), maximum lactate concentration (<i>p</i> = .720), and maximum heart rate (<i>p</i> = .884). During the exercise, no significant differences were observed in lactate and glucose concentrations, heart rate, or ventilatory parameters (ps > .050). However, significant differences (<i>p</i> < .001) in blood glucose concentrations were noted at rest and during the warm-up phase.</p><p><strong>Conclusions: </strong>The effect of the tested sports drink compositions on performance during the selected exercise protocol to voluntary exhaustion appears minimal. This study found no significant differences between the solutions and the placebo. Thus, it can be concluded that consuming a dextrose-based solution before exercise did not offer any performance advantage over water. The additional substances included in solutions B, C, and D did not influence performance, carbohydrate metabolism, or fat metabolism during the exercise.</p>","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"22 1","pages":"2516004"},"PeriodicalIF":4.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12138928/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144225832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Effects of milk fat globule membrane ingestion with exercise on physical strength in healthy young adults: a randomized double-blind, placebo-controlled trial.","authors":"Kyosuke Nakayama, Kyoko Ito, Yoshihiko Minegishi, Noriyasu Ota, Shukuko Ebihara, Chiaki Sanbongi","doi":"10.1080/15502783.2025.2535372","DOIUrl":"10.1080/15502783.2025.2535372","url":null,"abstract":"<p><strong>Background: </strong>The milk fat globule membrane (MFGM) is a structural membrane that covers the globules of triglycerides dispersed in an emulsion of milk. In previous human studies, MFGM ingestion combined with light aerobic exercise training improved agility in elderly individuals. The purpose of this study was to examine whether 4 weeks of daily ingestion of MFGM combined with power training improves instantaneous physical strength - muscle strength, agility, and muscle power compared with placebo (whey protein isolate) in healthy young adults.</p><p><strong>Method: </strong>The study was designed as a randomized, double-blind, and placebo-controlled trial. Ninety-eight healthy young adults aged 20-49 completed the study intervention, and they received either an MFGM powder containing 1.7 g of fat and 160 mg of sphingomyelin or an isocaloric placebo powder daily throughout 4 weeks (3 times/week) of power training. Physical strength tests and body composition measurements were conducted before and after the four-week intervention. An analysis of covariance (ANCOVA) model with baseline values as a covariate was carried out to test differences in post intervention values between groups.</p><p><strong>Results: </strong>Ingestion of MFGM significantly improved peak torque (<i>p</i> = 0.003) and average power (<i>p</i> = 0.019) of isokinetic knee extensors, leg press 1 repetition maximum (RM) (<i>p</i> = 0.004) and sit-ups reps (<i>p</i> = 0.030), but not indicators of agility, compared with placebo after the 4-week intervention. There were no significant changes in lean body mass during the intervention period in either group and no significant differences between groups.</p><p><strong>Conclusions: </strong>We conclude that daily MFGM supplementation combined with power training are effective to improve instantaneous physical strength, such as muscle strength and power, compared with placebo in healthy young adults.</p>","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"22 1","pages":"2535372"},"PeriodicalIF":4.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12281649/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144667858","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Blaine S Lints, Adam T Harrison, Sten O Stray-Gundersen, Gianna F Mastrofini, Riccardo F Romersi, Noah K Nakagawa, Mackenzie B Yoder, Chimaobim E Martin-Diala, Alexa J Chandler, R Davis Moore, Shawn M Arent
{"title":"A caffeine and theacrine combination improves cognitive performance in tactical personnel under physically fatiguing conditions.","authors":"Blaine S Lints, Adam T Harrison, Sten O Stray-Gundersen, Gianna F Mastrofini, Riccardo F Romersi, Noah K Nakagawa, Mackenzie B Yoder, Chimaobim E Martin-Diala, Alexa J Chandler, R Davis Moore, Shawn M Arent","doi":"10.1080/15502783.2025.2536146","DOIUrl":"10.1080/15502783.2025.2536146","url":null,"abstract":"<p><strong>Background: </strong>Optimizing human performance under stressful physical and cognitive conditions is paramount during high-stakes military operations. As such, interventions to improve warfighter performance by mitigating task-induced cognitive performance deficits are necessary. While caffeine is the most widely consumed psychoactive substance in the world, common side effects (i.e. anxiousness, micro-saccades, irritability) may be detrimental to warfighter operations. Theacrine, a purine alkaloid similar in structure to caffeine but with a longer half-life, less habituation, and fewer side effects, is proposed as a caffeine-alternative to enhance cognitive resilience.</p><p><strong>Methods: </strong>Tactically trained participants (<i>n</i> = 20; F = 5; <i>M</i> = 16; age = 21.5 ± 3.8 y) completed one baseline and three experimental visits. Baseline included familiarization with cognitive tasks and a graded exercise test to determine VO<sub>2max</sub>. Experimental sessions, separated by ≥96 hours, were double-blind, placebo-controlled, and randomized. Participants completed cognitive testing (Dynavision, Trazer, Object Hit and Avoid, Anti-Saccade, Two-Back), consumed either 300 mg caffeine (CAF), 150 mg caffeine +150 mg theacrine (CTC), or placebo (PLA), and repeated cognitive tests 60-min post supplementation. After a high-intensity interval exercise session (10 intervals at >90% VO<sub>2max</sub> with recovery), reaction time (RT) tests were repeated after the 4th and 8th intervals, as well as immediately and 30-min post-exercise. Heart rate was measured continuously. Change scores were calculated from baseline, and data analyzed using repeated measures ANOVA (α = 0.05) with Bonferroni correction.</p><p><strong>Results: </strong>Both CAF and CTC consistently enhanced cognitive and physical performance compared to PLA. In the Two-Back task, CTC showed significantly higher total accuracy (<i>p</i> < 0.01), while both CAF and CTC had fewer target (<i>p</i> < 0.01) and non-target errors (CAF: <i>p</i> = 0.03; CTC: <i>p</i> < 0.01) than PLA. CTC also had significantly faster RTs (<i>p</i> = 0.03) and lower RT variability for non-target trials compared to both PLA and CAF (<i>p</i> < 0.01). For the Dynavision Go/NoGo task, both CTC (<i>p</i> = 0.01) and CAF (<i>p</i> = 0.03) had significantly faster RTs than PLA, regardless of time point. Post-exercise, accuracy (<i>p</i> = 0.01) and RTs (<i>p</i> < 0.01) improved significantly compared to post-supplement. In the Object Hit & Avoid task, CAF and CTC significantly improved task accuracy (<i>p</i> < 0.01) while reducing omission (<i>p</i> < 0.01) and commission errors (<i>p</i> < 0.01) compared to PLA. HRV measures (RMSSD, NN intervals, SDNN) significantly increased post-supplementation (<i>p</i> < 0.01) but decreased immediately (<i>p</i> < 0.01) and 30 min post-exercise (<i>p</i> < 0.01). Blood lactate significantly declined at 5 (<i>p</i> < 0.01) and 10 min (<i>p</i> < 0.01) post-exe","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"22 1","pages":"2536146"},"PeriodicalIF":4.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144690642","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Nutritional strategies for minimizing gastrointestinal symptoms during endurance exercise: systematic review of the literature.","authors":"Janez Mlinaric, Nina Mohorko","doi":"10.1080/15502783.2025.2529910","DOIUrl":"10.1080/15502783.2025.2529910","url":null,"abstract":"<p><strong>Background: </strong>The gastrointestinal (GI) tract plays a critical role in achieving peak athletic performance either during training or in competitions. Despite its significance, the GI tract's role in the training process of athletes is often neglected, resulting in frequent GI symptoms. These disturbances are particularly prevalent in endurance sports, where GI function is commonly compromised, leading to adverse effects on performance. In this review, we examine potential nutritional causes of the GI symptoms and provide possible solutions to mitigate them, aiming to enhance athletes' overall performance and well-being.</p><p><strong>Methods: </strong>PRISMA methodology was used to search through PubMed Database from January 2023 to March 2023. The selected studies were comprised of randomized controlled trials, crossover trials and case studies.</p><p><strong>Results: </strong>Twenty-nine studies met the inclusion criteria for this systematic review. The studies were categorized into five distinct areas of research on GI symptoms in endurance exercise: gut training protocols, effects of different carbohydrate solutions and mixtures, low FODMAP diet, hydrogel CHO technology, and probiotic supplementation.Gut training protocols seem promising in improving GI symptoms over time. Optimizing carbohydrate intake during exercise according to current recommendations has been associated with lower incidence and severity of GI symptoms as well. The low FODMAP diet also shows potential to reduce GI symptoms, although its restrictive nature could negatively affect athletes in other ways. Hydrogel carbohydrate products, at present, do not demonstrate any benefits over standard carbohydrate products. Probiotic supplementation shows mixed evidence regarding its effectiveness in alleviating and reducing GI symptoms during endurance exercise.</p><p><strong>Conclusion: </strong>We have acknowledged that the onset of GI symptoms is very complex, and that onset is influenced by a huge variety of factors. It should be emphasized that the elimination of GI symptoms in each athlete must be approached individually and thoughtfully.</p>","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"22 1","pages":"2529910"},"PeriodicalIF":4.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12258207/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144618725","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Raúl Domínguez, Inmaculada López-León, Javier Moreno-Lara, Esteban Rico, Antonio J Sánchez-Oliver, Ángela Sánchez-Gómez, Javier Pecci
{"title":"Sport supplementation in competitive swimmers: a systematic review with meta-analysis.","authors":"Raúl Domínguez, Inmaculada López-León, Javier Moreno-Lara, Esteban Rico, Antonio J Sánchez-Oliver, Ángela Sánchez-Gómez, Javier Pecci","doi":"10.1080/15502783.2025.2486988","DOIUrl":"https://doi.org/10.1080/15502783.2025.2486988","url":null,"abstract":"<p><strong>Background: </strong>Competitive swimmers have a high prevalence of sports supplement (SS) consumption. However, only a few SS are scientifically proven to be safe, effective, and legal. Therefore, before incorporating supplements to enhance performance and health in competitive swimming, it is crucial to conduct an analysis and review to assess their effects. The objective of this study was to analyze the demonstrated effects of SS, as reported in published studies, on the swimming performance of competitive swimmers.</p><p><strong>Methods: </strong>Following PRISMA guidelines, a systematic search was conducted across six databases for the selection of studies included in this review. Studies that analyzed the effects of sports supplementation compared to placebo were included and subjected to meta-analysis.</p><p><strong>Results: </strong>This revision included 23 studies, 16 of them (69.6%) qualified as excellent and 7 (30.4%) as good at the methodological level based on the punctuation in the PEDro scale. The systematic review included 422 swimmers (61.8% male, 38.2% female), with distances assessed ranging from 50 m to 800 m, including studies employing interval procedures. Creatine showed a significant effect (ES = -0.46; 95% CIs = -0.75 to -0.17, <i>p</i> = 0.002; I<sup>2</sup> = 11%) on swimming performance, while the rest of the analyzed supplements did not show significant effects (all <i>p</i> > 0.05).</p><p><strong>Conclusions: </strong>Creatine supplementation demonstrated ergogenic benefits for competitive swimmers, although the evidence supporting the use of this supplement is still limited. Sodium bicarbonate and β-alanine may enhance performance in distances with higher glycolytic demands, while caffeine is effective at dosages of 3-6 mg/kg administered 60 min before exercise. Further research is needed to confirm the potential ergogenic effects of other supplements, such as beetroot juice.</p>","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"22 1","pages":"2486988"},"PeriodicalIF":4.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11986859/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144041672","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Effects of different dietary supplements on athletic performance in soccer players: a systematic review and network meta-analysis.","authors":"Hua Luo, Tengku Fadilah Tengku Kamalden, Xiaolin Zhu, Changqing Xiang, Nurul Amelina Nasharuddin","doi":"10.1080/15502783.2025.2467890","DOIUrl":"10.1080/15502783.2025.2467890","url":null,"abstract":"<p><strong>Background: </strong>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.</p><p><strong>Methods: </strong>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.</p><p><strong>Results: </strong>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. <i>Kaempferia parviflora</i> (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.</p><p><strong>Conclusions: </strong>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, <i>Kaempferia parviflora</i>, melatonin, and sodium pyruvate, can improv","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"22 1","pages":"2467890"},"PeriodicalIF":4.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11843665/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143458398","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
B Charlesson, J Jones, C Abbiss, P Peeling, S Watts, C T Christophersen
{"title":"Training load influences gut microbiome of highly trained rowing athletes.","authors":"B Charlesson, J Jones, C Abbiss, P Peeling, S Watts, C T Christophersen","doi":"10.1080/15502783.2025.2507952","DOIUrl":"10.1080/15502783.2025.2507952","url":null,"abstract":"<p><strong>Background: </strong>Despite the importance of the gut microbiome on physical performance and health, little is known on the impact of training on an athlete's gut health.</p><p><strong>Objective: </strong>This study investigates the effect of training load on markers of gut health.</p><p><strong>Methods: </strong>Whole stool (24 h) samples were collected from 23 highly trained rowers (mean ± SD; age 19.2 ± 1.1 y; weight 80.1 ± 11.4 kg; height 1.83 ± 0.09 m) following periods of high (HT) and low training load (LT). The microbiome and short-chain fatty acid concentrations were characterized from the whole stool samples. Three-day weighted food records were used to determine diet quality (ADIcore), macronutrient, and fiber intakes during HT and LT.</p><p><strong>Results: </strong>By design, training duration (147%) and intensity (130%) were greater during (HT), compared with (LT) (<i>p</i> < 0.001). Carbohydrate, fat, protein, and fiber intake remained stable, but ADIcore was higher in HT (55 ± 10) compared with LT (49 ± 9; t(15) = 2.78, <i>p =</i> 0.014; CI: 1.34 to 10.155). Stool frequency (1.11 ± 0.47 vs 0.67 ± 0.76; <i>p =</i> 0.007) was lower in HT compared with LT, and a greater number of participants were unable to produce a stool sample during LT (8% vs 47%). Short chain fatty acid (SCFA), propionic (120.64 ± 30.06 mm vs 91.35 ± 34.91 mm; <i>p =</i> 0.007), and butyric acid (104.76 ± 50.02 vs 64.23 ± 22.05 mm, <i>p =</i> 0.003) concentrations were lower in HT compared with LT. Alpha diversity, Shannon-Wiener diversity index (3.43 ± 0.37 vs 3.67 ± 0.34, <i>p =</i> 0.09) was lower in HT than LT. The abundance of the dominant <i>Bacteroidia</i> was greater at HT compared to LT and ratio of firmicutes to <i>Bacteroidota</i> (<i>n</i> = 16, 1.31 ± 1.19 vs 4.29 ± 3.88, t(15) = -3.44, <i>p =</i> 0.04, CI = -4.82 to -1.13) was lower in HT compared to LT.</p><p><strong>Conclusion: </strong>Results of this study indicate that gut microbiome, SCFA concentrations, stool frequency, and diet quality vary between periods of high and low training load in athletes. The relationship between these factors and impact of such changes in gut health is currently unclear and warrants further investigation.</p>","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"22 1","pages":"2507952"},"PeriodicalIF":4.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12100958/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144120016","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}