Journal of the International Society of Sports Nutrition最新文献

{"title":"International society of sports nutrition position stand: β-hydroxy-β-methylbutyrate (HMB).","authors":"John A Rathmacher, Lisa M Pitchford, Jeffrey R Stout, Jeremy R Townsend, Ralf Jäger, Richard B Kreider, Bill I Campbell, Chad M Kerksick, Patrick S Harty, Darren G Candow, Brandon M Roberts, Shawn M Arent, Douglas S Kalman, Jose Antonio","doi":"10.1080/15502783.2024.2434734","DOIUrl":"10.1080/15502783.2024.2434734","url":null,"abstract":"<p><p>Position Statement: The International Society of Sports Nutrition (ISSN) bases the following position stand on an analysis of the literature regarding the effects of β-Hydroxy-β-Methylbutyrate (HMB). The following 12 points have been approved by the Research Committee of the Society: 1. HMB is a metabolite of the amino acid leucine that is naturally produced in both humans and other animals. Two forms of HMB have been studied: Calcium HMB (HMB-Ca) and a free acid form of HMB (HMB-FA). HMB-FA appears to lead to increased appearance of HMB in the bloodstream when compared to HMB-Ca, though recent results are mixed. 2. The available safety/toxicity data suggest that chronic HMB-Ca and HMB-FA consumption are safe for oral HMB supplementation in humans up to at least one year. 3. There are no negative effects of HMB-Ca and HMB-FA on glucose tolerance and insulin sensitivity in humans. There may be improvements in glucose metabolism in younger adults. 4. The primary mode of action of HMB appears to be through its dual mechanism to enhance muscle protein synthesis and suppress muscle protein breakdown. HMB's activation of mTORC1 is independent of the leucine-sensing pathway (Sestrin2-GATOR2 complex). 5. HMB may help reduce muscle damage and promote muscle recovery, which can promote muscle growth/repair. HMB may also have anti-inflammatory effects, which could contribute to reducing muscle damage and soreness. 6. HMB consumption in close proximity to an exercise bout may be beneficial to increase muscle protein synthesis and attenuate the inflammatory response. HMB can provide a beneficial physiological effect when consumed both acutely and chronically in humans. 7. Daily HMB supplementation (38 mg/kg body weight) in combination with exercise training may improve body composition through increasing lean mass and/or decreasing fat mass with benefits in participants across age, sex, and training status. The most pronounced of these improvements in body composition with HMB have been observed in studies with robust resistance training programs and dietary control. 8. HMB may improve strength and power in untrained individuals, but its performance benefits in trained athletes are mixed and increase with an increase in study duration (>6 weeks). HMB's beneficial effects on athletic performance are thought to be driven by improved recovery. 9. HMB supplementation appears to potentially have a positive impact on aerobic performance, especially in trained athletes. The mechanisms of the effects are unknown. 10. HMB supplementation may be important in a non-exercising sedentary and aging population to improve muscle strength, functionality, and muscle quality. The effects of HMB supplementation with exercise are varied, but the combination may have a beneficial effect on the treatment of age-associated sarcopenia under select conditions. 11. HMB may be effective in countering muscle disuse atrophy during periods of inactivity due to illness or injury. The ","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"22 1","pages":"2434734"},"PeriodicalIF":4.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11740297/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142854635","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":"Efficacy of time restricted eating and resistance training on body composition and mood profiles among young adults with overweight/obesity: a randomized controlled trial.","authors":"Tingting Cui, Yichao Sun, Weibing Ye, Yubo Liu, Mallikarjuna Korivi","doi":"10.1080/15502783.2025.2481127","DOIUrl":"10.1080/15502783.2025.2481127","url":null,"abstract":"<p><strong>Background/objective: </strong>Dietary restriction or exercise regimens can promote weight loss or physical fitness among patients with obesity. However, intervention-associated adverse effects may impede patients' motivation to participate in dietary/exercise interventions. We examined the effects of time restricted eating (TRE) with or without resistance training (RT) on body composition, mood profile, and sleep quality in young college adults with overweight or obesity.</p><p><strong>Methods: </strong>Fifty-four young college students with overweight/obesity were randomized into control (CON), TRE, RT, and TRE plus RT (TRE+RT) trials. The TRE trials restricted to an eating window of 10-hour/day for 8-week. The RT trials performed supervised resistance exercise, while the control trial maintained a regular lifestyle. Changes in body composition variables, blood pressure, mood status, and sleep quality were measured before and after the intervention.</p><p><strong>Results: </strong>TRE intervention alone or in combination with RT significantly (<i>p</i> < 0.01) decreased body weight (>2 kg) and BMI (~1 kg/m²) in adults with overweight/obesity. Both RT alone and combined with TRE substantially decreased fat mass by 1.1 ± 0.5 and 3.2 ± 0.4 kg, respectively. The decreased fat mass was greater in the combination trial than in the RT trial, whereas TRE alone had no effect. In contrast, fat-free mass was significantly (<i>p</i> < 0.01) decreased with TRE (-2.3 ± 06 kg), increased with RT (1.6 ± 0.3 kg), and was stably maintained with combination interventions. The reduced waist and hip circumferences in the TRE (<i>p</i> < 0.01) were similar to those in the TRE+RT trials, however, RT alone had no effect. Time and group interaction showed a large effect size (partial eta squared) for all body composition variables. In addition, RT with or without TRE notably decreased diastolic blood pressure (RT: -5.5 ± 1.9 mmHg, TRE+RT: -4.1 ± 1.5 mmHg, <i>p</i> < 0.05). Mild anxiety levels at baseline in RT (4.8 ± 2.6) and TRE+RT (4.1 ± 3) trials were found to be normal at postintervention in TRE+RT (3.6 ± 1.7) but not in RT (5.6 ± 3.5). No depression or stress was recorded among the participants during the intervention. The reported poor sleep quality among participants at baseline was significantly improved with RT (4.8 ± 2.9; <i>p</i> < 0.05), and tended to improve with TRE+RT interventions (4.5 ± 1.9).</p><p><strong>Conclusions: </strong>10-hour TRE is beneficial for weight/fat loss without affecting mood status. However, TRE combined with RT might be more effective for weight/fat loss, maintaining muscle mass, and good quality of sleep among young adults with overweight or obesity.</p>","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"22 1","pages":"2481127"},"PeriodicalIF":4.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11926902/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143663708","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":"Neither pre-sleep nor post-exercise protein consumption influences resistance exercise training adaptations in older adults.","authors":"Alex O Klemp, Michael J Ormsbee, Mingchia Yeh, Chester M Sokolowski, Do-Houn Kim, Lynn B Panton, Jeong-Su Kim","doi":"10.1080/15502783.2025.2519511","DOIUrl":"10.1080/15502783.2025.2519511","url":null,"abstract":"<p><strong>Purpose: </strong>Limited data exists that compare pre-sleep versus post-exercise protein intake during resistance exercise training (RET) in older adults. This study examined whether 40 g of protein consumed post-exercise (PRP) or pre-sleep (PSP) enhances muscle thickness (MT) and strength compared to RET alone (RETO) in older men.</p><p><strong>Methods: </strong>Thirty untrained older men (65.7 ± 4.0 yrs) completed 12 weeks of supervised RET (2×/week) and were randomized to PRP (<i>n</i> = 9), PSP (<i>n</i> = 11), or RETO (<i>n</i> = 10). MT of the vastus lateralis (VL), rectus femoris (RF), and vastus intermedius (VI) and 1-repetition maximum (1-RM) for leg and chest press were assessed at weeks 0, 6, and 12.</p><p><strong>Results: </strong>VL (0 to 12 weeks: + 0.16 cm, 95% C.I. [0.06, 0.25]), RF (0 to 12 weeks: + 0.13 cm, 95% C.I. [0.03, 0.23]), and VI MT (0 to 12 weeks: + 0.18 cm, 95% C.I. [0.05, 0.31]) and chest press (0 to 12 weeks: + 10.9 kg, 95% C.I. [5.50, 16.3]) and leg press (0 to 12 weeks: + 28.3 kg, 95% C.I. [19.63, 37.1]) 1-RM increased (<i>p</i> < 0.050) with no group differences.</p><p><strong>Conclusion: </strong>Consuming 40 g of protein post-exercise or pre-sleep did not enhance RET-induced improvements in muscle thickness or strength in older adults with adequate baseline protein intake (≥1.0 g/kg/day). RET alone elicited significant gains, emphasizing that adherence to training and meeting daily protein requirements are more critical than timing strategies for untrained older adults. ClinicalTrials.gov identifier: NCT05922475, 06/23/2023, retrospectively registered.</p>","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"22 1","pages":"2519511"},"PeriodicalIF":4.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144333411","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":"The effects of mental fatigue and caffeine on basketball performance: insights from a crossover study.","authors":"Mehdi Hemmat, Gholamhosein Nazemzadegan, Alireza Niknam, Farhad Daryanoosh, Maryam Koushkie Jahromi","doi":"10.1080/15502783.2025.2541010","DOIUrl":"10.1080/15502783.2025.2541010","url":null,"abstract":"<p><strong>Background: </strong>The interactive effect of mental fatigue and caffeine consumption on sport performance is not clear. This study aimed to investigate the impact of mental fatigue and caffeine gum consumption on power and skill performance in recreationally trained male basketball players.</p><p><strong>Methods: </strong>A randomized, double-blind, crossover design was used, with twenty male participants (age: 16.7 ± 0.86 years, body mass: 79.6 ± 8.2 kg, height: 183.2 ± 8.6 cm, training experience ≥ 3 years). Participants completed four testing sessions under the following conditions: (1) no mental fatigue with placebo gum, (2) mental fatigue with placebo gum, (3) no mental fatigue with caffeine gum, and (4) mental fatigue with caffeine gum. The sessions were separated by one week. Mental fatigue was induced through a 30-minute Stroop task, and caffeine gum (50 mg of caffeine per piece) was administered 15 minutes before performance testing. Power and skill performance were assessed via vertical jump height, V-CUT dribbling test, medicine ball throw, and stationary two-point shooting, with three attempts per test.</p><p><strong>Results: </strong>Mental fatigue significantly increased time to react for congruent name and color (Z = 3.9, <i>p</i> < 0.001) and incongruent name and color (Z = 3.9, <i>p</i> < 0.001), as well as perceived fatigue (Z = 3.9, <i>p</i> < 0.001) after the Stroop task. Performance analysis revealed a significant main effect of condition on vertical jump height (F = 2.9, <i>p</i> = 0.04) and V-CUT dribbling performance (F = 4.4, <i>p</i> = 0.007), but not on medicine ball throw, change of direction test, or stationary two-point shooting (<i>p</i> > 0.05). Mental fatigue (mental fatigue with placebo gum) significantly impaired vertical jump height (<i>p</i> = 0.008) and V-CUT dribbling performance (<i>p</i> = 0.049) compared to the no mental fatigue with placebo gum condition. No significant differences were found between other condition pairs for these performance measures.</p><p><strong>Conclusion: </strong>Mental fatigue negatively affects power and skill performance in basketball players, while caffeine gum consumption may offer a potential strategy to mitigate these effects. While caffeine gum attenuated some performance declines in the mental fatigue with caffeine gum condition compared to mental fatigue with placebo gum, these differences were not statistically significant. Future research should explore optimal caffeine doses and additional performance variables.</p>","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"22 1","pages":"2541010"},"PeriodicalIF":3.9,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12308885/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144731968","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":"Comparison of athlete diet index and body composition between professional and non-professional athletes: a comparative cross-sectional study.","authors":"Elaheh Dehghani, Zahra Gohari Dezfuli, Sakineh Shab Bidar, Fereshteh Torki, Tohid Seif Barghi, Kurosh Djafarian","doi":"10.1080/15502783.2025.2533497","DOIUrl":"10.1080/15502783.2025.2533497","url":null,"abstract":"<p><strong>Background: </strong>This study aimed to compare the Athlete Diet Index (ADI) and body composition between professional and nonprofessional athletes to better understand how differences in training and nutrition impact athletic performance and health.</p><p><strong>Method: </strong>A comparative cross-sectional design was used to analyze 183 athletes (99 professional, 84 nonprofessional) from various sports disciplines in Tehran. Data were collected on body composition parameters, including fat mass (FM) and fat free mass (FM) using bioelectrical impedance analysis (BIA) and the ADI, a validated tool for assessing diet quality.</p><p><strong>Results: </strong>The results revealed that professional athletes had significantly lower FM percentages (16.2% ± 7.1%) and higher FFM percentages (80.8% ± 6.8%) compared to their nonprofessional counterparts (FM 18.8% ± 9.9%, FFM 78.0% ± 9.6%). Additionally, professional athletes exhibited higher ADI scores, indicating better adherence to sports nutrition guidelines.</p><p><strong>Conclusions: </strong>These findings highlight the benefits of structured training and personalized nutrition in achieving favorable body composition. This study underscores the importance of personalized nutrition strategies for optimizing athletic health and performance, particularly for nonprofessional athletes who may not have access to professional dietary guidance. Further research is needed to explore the long-term effects of dietary and training interventions on body composition and athletic performance across various athlete populations.</p>","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"22 1","pages":"2533497"},"PeriodicalIF":4.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12261505/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144626654","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":"How reliable is the labeling of a commercial phytosteroid product? A 12-week randomized double-blind training study.","authors":"Joshua Dissemond, Tim Havers, Steffen Held, Stephan Geisler, Tihomir Kostov, Patrick Diel, Svea Türschmann, Maria K Parr, Eduard Isenmann","doi":"10.1080/15502783.2025.2540408","DOIUrl":"10.1080/15502783.2025.2540408","url":null,"abstract":"&lt;p&gt;&lt;strong&gt;Introduction: &lt;/strong&gt;Phytosteroids like 20-hydroxyecdysone (20E) and diosgenin (DSG) have shown promising anabolic and performance-enhancing effects in in vitro, animal, and human studies. Combining phytosteroids is common in supplements, with early in vitro research suggesting additive effects via distinct signaling pathways. However, human studies on the combined effects of 20E and DSG are lacking. This study aimed to evaluate the anabolic and performance-enhancing potential of a commercially available 20E and DSG supplement.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Methods: &lt;/strong&gt;Twenty-eight resistance-trained young men were recruited for this study. Participants were randomized into two groups: a 20E and DSG (EcDi) group, and a placebo (Plac) group. Both groups performed free-weight resistance training three times per week for 12 weeks. The EcDi group received a commercially available phytosteroid product three times a day (as recommended on the label), while the Plac group received a placebo product. Assessments were conducted at four time points (T0, T1 [4 weeks], T2 [8 weeks], T3 [12 weeks]) and included measurements of one-repetition maximum (1-RM) for the squat (SQ) and bench press (BP) exercises, as well as body weight (BW), fat-free mass (FFM), muscle mass (MM), fat mass (FM), and muscle thickness of the pectoralis major (PM) and the proximal, middle and distal regions of the anterior (i.e. &lt;i&gt;M. rectus femoris&lt;/i&gt; and &lt;i&gt;M. vastus intermedius&lt;/i&gt;) and lateral quadriceps femoris (i.e. &lt;i&gt;M. vastus lateralis&lt;/i&gt; and &lt;i&gt;M. vastus intermedius&lt;/i&gt;). Liver and kidney function, along with endocrine parameters, were measured via blood samples pre- and post-intervention. Additionally, the concentration of 20E and DSG in the product was measured by LC-MS/MS, and its biological activity was evaluated using C2C12 cells after the intervention. Data were analyzed using a linear mixed model (LMM).&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;Twenty-four participants completed the study successfully. Significant improvements in 1-RM SQ and BP were observed across both groups, indicating a time but no specific group effect. Similarly, significant time effects without group effects were found for FFM, MM, FM and muscle thickness (anterior quadriceps femoris at 30%, lateral quadriceps femoris at 50% and PM). Subsequent analyses of the supplement revealed that less than 1% of the claimed 20E concentration and 10.4% of the claimed DSG concentration were present in the capsules. In addition, no biological activity or hypertrophic effects were detected in the C2C12 cells.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusion: &lt;/strong&gt;This study demonstrated that the prescribed resistance training protocol resulted in significant anabolic and performance-enhancing effects that did not differ between groups. The lack of group-specific differences suggests that the tested phytosteroid supplement did not provide additional benefits. The significant discrepancy between the claimed and actual 20E and DSG concentr","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"22 1","pages":"2540408"},"PeriodicalIF":3.9,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12337734/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144804313","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":"Changes in taste and odor sensitivities during repeated bicycle ergometer exercises.","authors":"Masataka Narukawa, Kensuke Nojiri, Rina Matsuda, Momo Murata, Seiji Sakate, Sachiko Kuga, Hidetoshi Ue","doi":"10.1080/15502783.2024.2441769","DOIUrl":"10.1080/15502783.2024.2441769","url":null,"abstract":"<p><strong>Background: </strong>Effective nutritional support is essential for maintaining good performance during exercise. Taste and olfaction are key senses for food intake, and understanding how their sensitivities change during exercise is important for effective nutritional support. However, the effects of exercise on taste and odor sensitivities remain unclear. This study aimed to investigate changes in taste and odor sensitivities during repeated endurance exercise using a bicycle ergometer.</p><p><strong>Methods: </strong>A total of 20 women (mean age; 21.6 ± 0.2 years) participated in the study, completing four 60-minute segments, each comprising 50 minutes of bicycle ergometer exercise at an exercise intensity of 60% heart rate reserve and a 10-minute sensory test. The sensory tests were conducted five times in total: after each exercise segment and once before exercise as a control. Four concentrations (×0.5, ×0.75, ×1, and × 1.25) of a commercially available isotonic beverage were used as taste samples, and the subjects evaluated the taste intensity, preference, and odor intensity. Four types of food odorants were used as odor samples, and the subjects rated their preference. The subjects also reported their perceived fatigue levels during the taste and odor tests. Fatigue levels and taste intensity were rated using a 100-mm visual analogue scale, and taste and odor preferences and odor intensity were evaluated using a scoring method.</p><p><strong>Results: </strong>The degree of physical fatigue significantly increased with each successive bicycle exercise segment. The taste intensity and preference for beverages with higher concentrations increased as the number of exercise segments increased, showing a significant increase in taste intensity for the × 1.25 solution in the final segment compared with before the tests. On the other hand, no significant effect was observed on the perceived odor intensity of the isotonic beverages. Similarly, there was no significant effect on the preference for odor samples due to repeated exercise.</p><p><strong>Conclusions: </strong>These results suggest that taste sensitivity may change with prolonged exercise. Additionally, since odor intensity and preference were not significantly affected by repeated exercise, odor sensitivity may be less impacted by exercise than taste sensitivity.</p>","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"22 1","pages":"2441769"},"PeriodicalIF":4.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11654038/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142837209","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":"Comment on \"Association of low muscle mass index and sarcopenic obesity with knee osteoarthritis: a systematic review and meta-analysis\".","authors":"Jinxiang Peng, Haozhu Chen","doi":"10.1080/15502783.2025.2470230","DOIUrl":"10.1080/15502783.2025.2470230","url":null,"abstract":"","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"22 1","pages":"2470230"},"PeriodicalIF":4.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11873926/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143523751","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":"Individual responses to encapsulated caffeine and caffeine chewing gum on strength and power in strength-trained males.","authors":"Hamed Teimouri-Korani, Mohammad Hemmatinafar, Mark Et Willems, Rasoul Rezaei, Babak Imanian","doi":"10.1080/15502783.2025.2495228","DOIUrl":"https://doi.org/10.1080/15502783.2025.2495228","url":null,"abstract":"&lt;p&gt;&lt;strong&gt;Background: &lt;/strong&gt;Liquid-dissolved and encapsulated powder are two popular ways to consume caffeine for performance-enhancing effects. Caffeine in other delivery methods, such as chewing gums, orally dissolvable strips, gels, mouthwashes, energy drinks, and nasal sprays, is believed to be absorbed more quickly into the bloodstream. Inter-individual responses to caffeine's enhancing effects are recognized. The present study examined the inter-individual responses to the acute effects of encapsulated caffeine and caffeinated chewing gum on the lower-body isokinetic and isometric strength and power in strength-trained males.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Method: &lt;/strong&gt;A randomized, cross-over, placebo-controlled study was conducted with 15 strength-trained males (age: 25  ±  4 years, height: 176  ±  7 cm, weight: 75  ±  11 kg, habitual caffeine intake: 66  ±  15 mg·day&lt;sup&gt;-1&lt;/sup&gt;). Participants were randomly assigned to three conditions: i) caffeinated chewing gum (CG), ii) caffeine capsule (CC), and iii) starch capsule as a placebo (PLA). Participants consumed approximately 3 to 4.5 mg·kg&lt;sup&gt;-1&lt;/sup&gt; of caffeine 60 minutes before testing. The washout period between conditions was one week. Participants performed the Sargent jump test, followed by a 5-minute active recovery (walking). Subsequently, isokinetic strength and power (60°/s and 180°/s) and isometric strength (45° and 60°) parameters were measured for knee extensor and flexor muscles. Data were analyzed using one-way repeated measures ANOVA and Bonferroni post hoc tests, with significance set at &lt;i&gt;p&lt;/i&gt; ≤ 0.05. Responders to the caffeine conditions were identified using the smallest worthwhile change (SWC) analysis.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;In knee extensors, 1) average peak torque and power at 60°/s were higher in CC (&lt;i&gt;p&lt;/i&gt; = 0.045; + 11.2% and &lt;i&gt;p&lt;/i&gt; = 0.038; + 14.1%) and CG (&lt;i&gt;p&lt;/i&gt; = 0.044; + 7.3% and &lt;i&gt;p&lt;/i&gt; = 0.015; + 11.4%) compared to PLA with a co-response rate of 60% and 66%, 2) maximum voluntary isometric contraction at 45° (MVIC-45°) was higher in CC compared to PLA (&lt;i&gt;p&lt;/i&gt; = 0.031; + 10.1%), and 3) MVIC-60° was higher in CG compared to PLA (&lt;i&gt;p&lt;/i&gt; = 0.037; + 10.1%) with a co-response rate of 60%. In knee flexors, 1) time to peak torque at 60°/s was higher in CG compared to PLA (&lt;i&gt;p&lt;/i&gt; = 0.011; + 18.2%) with a co-response rate of 46%, 2) average rate of force development at 60°/s was higher in CC (&lt;i&gt;p&lt;/i&gt; = 0.007; + 24.1%) and CG (&lt;i&gt;p&lt;/i&gt; = 0.050; + 20.6%) compared to PLA with a co-response rate of 53%, and 3) average power at 180°/s was higher in CC compared to PLA (&lt;i&gt;p&lt;/i&gt; = 0.033; + 18%) with a co-response rate of 46%. However, there were no differences between other strength indicators in the knee extensors and flexors between the different conditions. Vertical jump height (VJH) was higher in CC (&lt;i&gt;p&lt;/i&gt; = 0.001; + 5.5%) and CG (&lt;i&gt;p&lt;/i&gt; = 0.001; + 6.) compared to PLA, with a co-response rate of 53%.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusion: &lt;/strong&gt;Caffeine s","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"22 1","pages":"2495228"},"PeriodicalIF":4.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12010647/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143979150","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":"Assessing the risk of low energy availability, bone mineral density and psychological strain in endurance athletes.","authors":"Charlotte R Gowers, Christopher J McManus, Henry C Chung, Ben Jones, Jamie Tallent, Sally P Waterworth","doi":"10.1080/15502783.2025.2496448","DOIUrl":"https://doi.org/10.1080/15502783.2025.2496448","url":null,"abstract":"<p><strong>Background: </strong>Adequate energy intake is crucial for athletic performance and recovery. However, many endurance athletes experience Low Energy Availability (LEA), which, if prolonged, can detrimentally impact both health and performance.</p><p><strong>Methods: </strong>A total of 55 endurance athletes (23 females; 45  ±  13 years, 1.64  ±  0.06 m, 64.4  ±  11.4 kg and 32 males; 44  ±  13 years, 1.76  ±  0.18 m, 78.8  ±  9.2 kg) underwent physical assessments and completed questionnaires on dietary habits, training loads, and psychological stress. Dual-Energy X-ray Absorptiometry (DEXA) scans measured bone mineral density (BMD) in the lumbar L1-L4 spine, and body composition. Risk of LEA burnout, and psychological strain were assessed using sport-specific questionnaires.</p><p><strong>Results: </strong>Seventy-seven percent of female athletes were identified as at risk of LEA by the LEAF-Q. These females had higher body weight and fat percentage than those at low risk of LEA. Male athletes had a higher prevalence of low lumbar BMD (31%) compared to females, associated with older age, and longer training histories. Although only 9% of female athletes had low-BMD, those affected had a history of amenorrhea and were identified as at risk of LEA by the LEAF-Q.</p><p><strong>Conclusion: </strong>A high proportion of endurance athletes had low-BMD and were at risk of LEA. This underscores the need for targeted nutritional strategies to mitigate the risks associated with LEA and promote overall athlete well-being.</p>","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"22 1","pages":"2496448"},"PeriodicalIF":4.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12016249/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143971082","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}