International journal of sport nutrition and exercise metabolism最新文献

{"title":"Comparison of Ramp and Step Graded Cardiopulmonary Exercise Tests for the Estimate of Substrate Oxidation Rates in Recreationally Active Individuals.","authors":"Lorenzo Nesti, Lorenza Santoni, Silvia Frascerra, Martina Chiriacò, Andrea Natali","doi":"10.1123/ijsnem.2024-0236","DOIUrl":"https://doi.org/10.1123/ijsnem.2024-0236","url":null,"abstract":"<p><p>Fat oxidation rates are key determinants of exercise capacity and metabolic health, evaluated by indirect calorimetry during step graded exercise test. We sought to verify whether indirect calorimetry applied to ramp graded exercise test provides comparable results to the reference test and to identify the physiological bases of possible dissimilarities. To this aim, 14 healthy volunteers performed two cardiopulmonary exercise tests with concomitant stress echocardiography according to standard protocols until limit of tolerance on separate days, in randomized order. Compared at matched exercise intensities, expressed as percentage of estimated maximal rate of oxygen uptake (%V˙O2max), indirect calorimetry applied to ramp provided identical kinetics of macronutrient oxidation, with a negligible (7%, p > .05) constant overestimation of fat and underestimation of carbohydrate oxidation rates. Despite identical hemodynamic and ventilatory parameters throughout the tests, we observed a minute downward shift of the Δ V˙CO2/Δ V˙O2 intercept with ramp in comparison to step (-0.05 ± 0.09 L/min; p = .077) due to delayed alignment of gas exchange to work rate, which explains the differences in substrate oxidation values between the two tests. Ramp macronutrient oxidation rates were fully normalized by correcting the stoichiometric equations for the Δ V˙CO2/Δ V˙O2 intercept difference. In conclusion, cardiopulmonary and metabolic responses are dependent on exercise intensity and not on the protocol used. Indirect calorimetry applied to ramp protocols correctly identifies the kinetics of macronutrient oxidation while introducing minimal differences in the absolute values due to different gas-exchange response that can be mathematically corrected by applying the Δ V˙CO2/Δ V˙O2 correction factor.</p>","PeriodicalId":14334,"journal":{"name":"International journal of sport nutrition and exercise metabolism","volume":" ","pages":"1-10"},"PeriodicalIF":3.0,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144186979","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of Carotenoid Supplementation on Exercise-Induced Oxidative Stress: A Systematic Review and Meta-Analysis of Randomized Clinical Trials.","authors":"Xing Ye, Yanchun Li","doi":"10.1123/ijsnem.2024-0256","DOIUrl":"https://doi.org/10.1123/ijsnem.2024-0256","url":null,"abstract":"<p><strong>Objective: </strong>This study aims to investigate the potential effects of carotenoid supplementation on mitigating exercise-induced oxidative stress and to provide guidance for future research.</p><p><strong>Methods: </strong>We conducted a systematic review and meta-analysis using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched multiple databases from inception to August 2024 for randomized clinical trials investigating the effects of carotenoid supplementation on biomarkers of oxidative stress, inflammatory markers, antioxidant levels, and metabolic parameters in the context of exercise-induced oxidative stress. The search terms included \"carotenoids,\" \"supplementation,\" \"exercise,\" \"oxidative stress,\" \"inflammation,\" \"antioxidants,\" \"metabolic parameters,\" and their synonyms. Two reviewers independently extracted study data, with disagreements resolved by a third reviewer. Quality was assessed by the Cochrane risk-of-bias method. Random and fixed effects models were used for the analysis of standard mean differences (SMD) or weighted mean differences (MDs) with 95% confidence intervals (CI).</p><p><strong>Results: </strong>A total of 12 studies were included in the final analysis. Carotenoid supplementation led to significant effects in assessing oxidative stress induced by exercise (overall oxidative stress: SMD = -0.55, 95% CI [-1.04, -0.06]; malondialdehyde: MD = -0.05, 95% CI [-0.09,-0.02]; total antioxidant capacity: MD = 0.03, 95% CI [0.02, 0.03]; 8-isoprostane: MD = -35.70, 95% CI [-59.32, -12.09]; lipid peroxide: SMD = -1.07, 95% CI [-1.94, -0.20]; and nitric oxide: MD = -8.07, 95% CI [-12.54,-3.59]), inflammatory markers (inflammatory levels: SMD = 1.63, 95% CI [0.81, 2.46]; interleukin levels: SMD = 1.54, 95% CI [0.69, 2.40]; and C-reactive protein: MD = 4.56, 95% CI [0.97, 8.14]), antioxidant levels (SMD = 0.84, 95% CI [0.14, 1.53]), and metabolic parameters (energy expenditure: SMD = -0.52, 95% CI [-0.78, -0.26]; p < .05).</p><p><strong>Conclusion: </strong>Carotenoid supplementation appears to attenuate exercise-induced oxidative stress and the inflammatory response and improve antioxidant levels and metabolic capabilities. However, these results may be influenced by participant variability or methodological differences. Further research with larger sample sizes, longer supplementation periods, higher doses, and carotenoid bioavailability is needed to confirm these findings.</p>","PeriodicalId":14334,"journal":{"name":"International journal of sport nutrition and exercise metabolism","volume":" ","pages":"1-18"},"PeriodicalIF":3.0,"publicationDate":"2025-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144127635","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Female Athletes Report Positive Experiences as Research Participants.","authors":"Ella S Smith, Alannah K A McKay, Kathryn E Ackerman, Kirsty J Elliott-Sale, Trent Stellingwerff, Rachel Harris, Louise M Burke","doi":"10.1123/ijsnem.2024-0182","DOIUrl":"https://doi.org/10.1123/ijsnem.2024-0182","url":null,"abstract":"<p><p>Given the underrepresentation of women in sports and exercise science research, we sought to understand the experiences of female athletes currently involved in applied sports and exercise science research to inform future studies and potentially increase participation rates. Accordingly, we investigated the experiences of 89 female athletes (n = 48 cyclists/triathletes, n = 19 race walkers, n = 22 National Rugby League Indigenous Women's Academy players) who participated in four separate studies of sports performance with different methodological characteristics. Participants completed a questionnaire upon study completion that queried prior research participation, reasons for participating and experiences during the current study. Across all 89 athletes, 81% were first-time research participants, with the primary barriers cited as a perceived lack of opportunities or being unaware of opportunities (93%). Participants rated an interest in the research outcome as the most important aspect influencing their decision to participate (90 ± 14 [out of 100]), followed by the opportunities to receive personalized results (84 ± 20) and education (78 ± 27). Most participants (87%) stated that they would apply the study findings to their sports involvement, while the remaining 13% reported that they required support to understand the application of results. The majority (94%) of participants indicated a willingness to participate in future studies, while the research experience was rated positively at a mean 77 out of 100. Ultimately, our findings uncovered a perceived lack of opportunity as the primary barrier to female athlete research participation. As such, opportunities for women to participate in high-quality studies should be prioritized.</p>","PeriodicalId":14334,"journal":{"name":"International journal of sport nutrition and exercise metabolism","volume":" ","pages":"1-11"},"PeriodicalIF":3.0,"publicationDate":"2025-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144017752","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Female Exercise Metabolism: Quality Assessment of Existing Knowledge Base and Key Challenges in Study Design.","authors":"Sarah Bagot, Jennifer Miles-Chan, Anthony C Hackney, Martine Duclos, Laurie Isacco","doi":"10.1123/ijsnem.2024-0095","DOIUrl":"10.1123/ijsnem.2024-0095","url":null,"abstract":"<p><p>A better understanding of the practical and methodological challenges inherent in accurately tracking female hormonal status would enhance the clarity of research findings in exercise metabolism. The purpose of this study was to conduct an objective assessment of the quality of existing literature in this area and to provide a general overview of the practical conditions and issues encountered in studies investigating substrate metabolism during exercise in women, both in those using (HC+) or not using (HC-) hormonal contraceptives. Forty-four articles were identified through systematic reviews, meta-analyses, and searches on PubMed/MEDLINE. A quality assessment framework was developed and applied using a double-blind scoring approach. The loss/exclusion of data between baseline and final analyses per study was quantified, and the main challenges were highlighted. A higher mean global score was observed in studies conducted among HC+ women (81%) than those among HC- women (46%). Although the dropout rates were rarely mentioned in HC+ women articles, the mean rate of participant/data loss in HC- groups was 22.1%. The rate of HC- participant loss was positively correlated with the global score (r = .504, p = .02). High-quality research may be easier to achieve in studies involving HC+ women compared with those involving HC- women. Studies on HC- women seem to face more practical challenges, such as tracking the menstrual cycle and targeting specific (sub)phases of the menstrual cycle, along with technical and feasibility limitations. Thus, although the framework for designing such studies exists, the quality assessment of the available literature emphasizes its challenge in terms of research implementation.</p>","PeriodicalId":14334,"journal":{"name":"International journal of sport nutrition and exercise metabolism","volume":" ","pages":"255-268"},"PeriodicalIF":3.0,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143566754","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Minimal Influence of Formulated Nutritional Interventions on Sleep and Next-Morning Physical Performance, Cognitive Function, and Postural Sway in Adult Males: A Randomized, Placebo-Controlled, Crossover Study.","authors":"Matthew Morrison, Jonathon Weakley, Gregory D Roach, Charli Sargent, Dean J Miller, Lara Nyman, Carissa Gardiner, Gabriella Munteanu, Matthew D Pahnke, Shona L Halson","doi":"10.1123/ijsnem.2024-0148","DOIUrl":"10.1123/ijsnem.2024-0148","url":null,"abstract":"<p><p>Athletes often experience poor sleep quality and quantity which may hinder physical performance and cognitive function. Presleep nutritional strategies may be an alternative to pharmacological interventions to improve sleep. The aim of this study was to examine the effect of two different doses of a nutritional intervention (both containing high Glycemic Index carbohydrate, whey, tryptophan, theanine, and 5'AMP) versus placebo on objective and subjective sleep, next-morning physical performance, cognitive function, and postural sway. Seventeen healthy, trained adult males completed three double-blind trials in a randomized, counterbalanced, crossover design. Participants were allocated to conditions using a Latin Square design. A (a) low-dose, (b) high-dose, or (c) placebo drink was provided 90 min before sleep each night. Polysomnography was used to measure objective sleep parameters. Cognitive function, postural sway, and subjective sleep quality were assessed 30 min after waking. Physical performance was assessed using a 10-min maximal effort cycling time trial each morning. All data were analyzed using linear mixed effects models and effect sizes were calculated using Cohen's d. This study was registered prospectively as a clinical trial with Australian New Zealand Clinical Trials Registry (registration number: NCT05032729). No significant main effects or improvements were observed in objective or subjective sleep parameters, physical performance, cognitive function, or postural sway. The low-dose intervention appeared to reduce N3 sleep duration compared with placebo (-13.6 min). The high-dose intervention appeared to increase N1 sleep duration compared with placebo (+7.4 min). However, the magnitude of changes observed were not likely to cause meaningful reductions in sleep quality and quantity.</p>","PeriodicalId":14334,"journal":{"name":"International journal of sport nutrition and exercise metabolism","volume":" ","pages":"192-205"},"PeriodicalIF":3.0,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143472472","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Caffeinated Ice Slushy Enhances 1,200 kJ Cycle Time-Trial Performance in the Heat.","authors":"Grant J Landers, Shannon Ward, Matthew Zimmermann","doi":"10.1123/ijsnem.2024-0164","DOIUrl":"10.1123/ijsnem.2024-0164","url":null,"abstract":"<p><p>This study aimed to assess the effects of caffeine ingestion incorporated into an ice slushy on cycling time-trial (CTT) performance in hot, humid conditions. Nine moderately trained recreational male cyclists or triathletes ingested 6.8 g/kg crushed ice with either 6% carbohydrate concentration only (CON) or 6% carbohydrate concentration and 3 mg/kg caffeine (CAF) consumed over a 30 min period prior to exercise in a single-blind, counterbalanced design. Postingestion, participants completed a CTT equating 1,200 kJ of work (∼40 km) in a climate-controlled chamber (33 °C and 60% relative humidity). Experimental sessions were separated by 7 days. During each CTT, rectal temperature, cycling time, heart rate, blood lactate, and ratings of perceived exertion and thermal sensation were measured at set intervals of work. The 1,200 kJ CTT was completed faster in CAF (4,716 ± 785 s) compared with CON (4,911 ±755 s) (p < .05); and split times were completed faster in CAF compared with CON from the 800 to 1,200 kJ timepoints of the CTT. Precooling lowered rectal temperature similarly in both CAF (-0.6 ± 0.2 °C) and CON (-0.6 ± 0.1 °C) (p > .05). No differences were observed between CAF and CON for heart rate, rating of perceived exertion, rating of perceived thermal sensation, or blood lactate across the measured time points (p > .05). Precooling with the combination of a carbohydrate-based ice slushy and caffeine resulted in improved CTT performance in hot conditions compared with a carbohydrate-based ice slushy alone. Therefore, the addition of caffeine to ice slushies might be considered by endurance athletes competing in the heat for enhanced performance gains.</p>","PeriodicalId":14334,"journal":{"name":"International journal of sport nutrition and exercise metabolism","volume":" ","pages":"225-231"},"PeriodicalIF":3.0,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143414070","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Repetitive Feeding-Challenge With Different Nutritional Densities on Markers of Gastrointestinal Function, Substrate Oxidation, and Endurance Exercise Performance.","authors":"Isabel G Martinez, Jessica R Biesiekierski, Christopher E Rauch, Ricardo J S Costa","doi":"10.1123/ijsnem.2024-0145","DOIUrl":"10.1123/ijsnem.2024-0145","url":null,"abstract":"<p><p>Gut-training has been shown to improve gastrointestinal tolerance, circulatory glucose availability, and exercise performance. The study aimed to investigate the effects of a repetitive feeding-challenge using fat versus carbohydrate (CHO) on markers of gastrointestinal function, glucose availability, and subsequent performance when challenged with a high-CHO load (87 g/hr) during exercise. Forty-four endurance athletes (mean ± SD [9 females and 35 males]: body mass: 71.2 ± 9.2 kg, height: 173.6 ± 7.0 cm, V˙O2max: 55.0 ± 6.1 ml·kg-1·min-1) completed a preintervention gut-challenge trial (T1), involving a 2 hr run (60% V˙O2max) while taking a CHO gel every 20 min (87 g/hr, 10% w/v), followed by a 1 hr self-paced distance test with ad libitum water. Participants were then randomized to a fat (fat feeding-challenge [FFC]; 20 g nut butter, 124 kcal, 11 g fat, 3 g protein, and 3 g CHO) or CHO supplement (CHO feeding-challenge [CFC]; 47 g CHO gel: 123 kcal, 29 g CHO) group to complete a 7-day repetitive feeding-challenge (1 hr exercise and supplement intake every 20 min with 290 ml water), followed by a gut-challenge retrial (T2). FFC did not differ from CFC in terms of resting orocecal transit time, feeding tolerance, or substrate oxidation during T1 and T2. Peak breath hydrogen was lower in FFC than CFC (p = .028) at T2. Total (FFC: 27%, p = .005 vs. CFC: 38%, p = .001) and upper gastrointestinal symptoms severity (FFC: 26%, p = .013 vs. CFC: 40%, p < .001) during exercise was reduced similarly between groups from T1 to T2. FFC covered more distance in T2 (11.51 ± 2.02 vs. 11.08 ± 2.02 km, p = .013), but not significantly different to CFC (p = .341). A repetitive feeding-challenge with fat does not enhance nor worsen gastrointestinal and fueling outcomes compared with a CHO repetitive feeding-challenge.</p>","PeriodicalId":14334,"journal":{"name":"International journal of sport nutrition and exercise metabolism","volume":" ","pages":"173-191"},"PeriodicalIF":3.0,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143364776","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Erratum. Sodium Hyperhydration Improves Performance With No Change in Thermal and Cardiovascular Strain in Female Cyclists Exercising in the Heat Across the Menstrual Cycle.","authors":"","doi":"10.1123/ijsnem.2025-0013","DOIUrl":"10.1123/ijsnem.2025-0013","url":null,"abstract":"","PeriodicalId":14334,"journal":{"name":"International journal of sport nutrition and exercise metabolism","volume":" ","pages":"269"},"PeriodicalIF":3.0,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143028781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sodium Hyperhydration Improves Performance With No Change in Thermal and Cardiovascular Strain in Female Cyclists Exercising in the Heat Across the Menstrual Cycle.","authors":"Lilia Convit, Liliana Orellana, Julien D Périard, Amelia J Carr, Stuart Warmington, Mégane Beaugeois, Anju Abraham, Rhiannon M J Snipe","doi":"10.1123/ijsnem.2024-0125","DOIUrl":"10.1123/ijsnem.2024-0125","url":null,"abstract":"<p><p>This study investigated the effect of sodium hyperhydration on thermal and cardiovascular strain and exercise performance in unacclimatized endurance-trained females exercising in the heat and whether effects differ between menstrual cycle (MC) Phase 1 (low estrogen and progesterone) and MC Phase 4 (moderate estrogen and high progesterone). Twelve female cyclists/triathletes completed four trials in a randomized, double-blinded, crossover design. Participants consumed 30 ml·kg-1 fat-free mass fluid with either sodium chloride (7.5 g·L-1) or placebo (sucrose) 2 hr prior to 75 min of steady-state cycling (60% V˙O2peak) followed by a 200-kJ time trial (TT) in 34 °C and 60% relative humidity, with both interventions completed during MC Phase 1 and Phase 4. Rectal temperature and heart rate were measured at baseline, every 5 min during steady state, every 50 kJ of TT, and TT completion. Body mass was measured every 30 min preexercise and pre and post steady state and TT to assess hydration status. Linear mixed models were fitted to estimate intervention and MC phase effect. There were no significant sodium hyperhydration or MC phase effects on rectal temperature or heart rate (p > .05). Body mass increased with sodium versus placebo (0.38 [0.02, 0.74] kg; p = .04), with a greater increase in MC Phase 4 (0.69 [0.17, 1.2] kg; p < .001). TT performance improved with sodium versus placebo (-1.55 [-2.46, -0.64] min; p = .001), with a greater improvement in MC Phase 4 (-1.85 [-3.16, -0.55] min; p = .005). Sodium hyperhydration is a promising heat mitigation strategy for females undertaking prolonged exercise in the heat, especially during MC Phase 4 and when fluid access is limited.</p>","PeriodicalId":14334,"journal":{"name":"International journal of sport nutrition and exercise metabolism","volume":" ","pages":"99-111"},"PeriodicalIF":3.0,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142728537","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evening Alpha-Lactalbumin Supplementation Alters Sleep Architecture and Reduces Morning Reaction Time in an Athletically Trained Population With Sleep Difficulties.","authors":"Jackson Barnard, Spencer Roberts, Michele Lastella, Damien L Callahan, Brad Aisbett, Dominique Condo","doi":"10.1123/ijsnem.2024-0094","DOIUrl":"10.1123/ijsnem.2024-0094","url":null,"abstract":"<p><p>Evening consumption of a whey protein rich in the amino acid tryptophan, alpha-lactalbumin (ALAC), has previously shown to benefit sleep-particularly among poor sleepers. Given trained populations often experience sleep difficulty, this study investigated whether evening supplementation of ALAC would influence sleep outcomes, mood, and next-day cognitive performance within a trained population with sleep difficulties. Nineteen trained participants (females, n = 11) with sleep difficulties (Athlete Sleep Screening Questionnaire: 8.1 ± 3.1; Pittsburgh Sleep Quality Index: 10.5 ± 4.1) completed this double-blinded, counterbalanced, randomized, crossover trial. Forty grams of ALAC or control were supplemented 2 hr presleep for three consecutive nights in a controlled environment, with sleep measured using dry electroencephalography. Blood samples were taken on the first evening of each experimental trial, with mood, sleepiness, and recovery assessed across the evening and morning. A cognitive testing battery was also completed each morning. During the ALAC condition, the primary findings were that participants had raised plasma tryptophan levels (p < .01), increased nonrapid eye movement Stage 2 sleep duration (CON: 205.9 ± 33.3; ALAC: 216.5 ± 33.1 min), reduced rapid eye movement duration (CON: 110.8 ± 27.9; ALAC: 99.7 ± 23.1 min), and improved reaction time in cognitive tests involving sensory motor speed, spatial orientation, and vigilant attention (p < .05). Data suggest evening supplementation of 40 g ALAC alters sleep architecture and improves next-morning reaction time in trained populations with sleep difficulties. Therefore, trained individuals experiencing sleep difficulty may benefit from acute ALAC supplementation to assist next-day performance. Future research should investigate this effect within habitual environments, outside of a tightly controlled setting.</p>","PeriodicalId":14334,"journal":{"name":"International journal of sport nutrition and exercise metabolism","volume":" ","pages":"215-224"},"PeriodicalIF":3.0,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143005481","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}