동충하초 (VO2max)

Objective: Seaweed and microalgae provide antioxidants, polyunsaturated fatty acids, and bioactive compounds that may enhance exercise performance and accelerate recovery. However, evidence remains inconsistent. This systematic review and meta-analysis aimed to evaluate the effects of algae-derived supplementation on exercise performance and physiological recovery outcomes in healthy and athletic adults. Methods: This review was registered in PROSPERO (CRD420251166723) and conducted in accordance with PRISMA 2020 guidelines. PubMed, Web of Science, Embase, Cochrane Library, EBSCO, and CNKI were systematically searched for randomized controlled trials (RCTs) evaluating algae supplementation in exercise contexts. Inclusion and exclusion criteria were defined based on the PICOS framework. Primary outcomes included VO2max, Time to exhaustion (TTE), maximal power output (WRmax), Time-Trial (TT) performance, and creatine kinase (CK). Standardized mean differences (SMDs) with 95% confidence intervals (CIs) were calculated using a random-effects model. Subgroup, sensitivity, and publication bias analyses were performed. Results: Twenty-two RCTs (n = 822) investigating Spirulina, Chlorella, brown-algal polysaccharides, or astaxanthin met inclusion criteria. Algae supplementation showed a suggestive improvement in VO2max (SMD = 0.88, 95% CI: 0.00-1.75) and significantly improved in TTE (SMD = 1.06, 95% CI: 0.16-1.96), with smaller effects on WRmax (SMD = 0.29, 95% CI: 0.03-0.55), and no significant benefit for TT performance (SMD = -0.27, 95% CI: -0.74 to 0.21). Regarding recovery, CK concentrations were significantly reduced (SMD = -0.78, 95% CI: -1.28 to -0.28). Subgroup analysis suggested greater effects for Chlorella supplementation, higher dosages, and aerobic training contexts; reductions in muscle-damage markers were more evident following resistance exercise. Sensitivity analyses supported the robustness of the main findings with minimal evidence of publication bias. Conclusions: Algae-derived supplements-particularly Spirulina and Chlorella-may modestly enhance aerobic exercise performance and attenuate exercise-induced muscle damage under certain conditions. Eff

OBJECTIVE: This systematic review and meta-analysis aimed to assess the effect of concurrent training (CT) on exercise capacity and quality of life in patients with chronic obstructive pulmonary disease (COPD), and to identify the optimal CT dose to enhance 6-min walk distance (6MWD). METHODS: Relevant randomized controlled trials (RCTs) examining the effects of CT on exercise capacity and quality of life in patients with COPD were identified through a comprehensive search of PubMed, Embase, Web of Science, Cochrane Library, Scopus, and SPORTDiscus. A multilevel Bayesian random-effects model was used to conduct both pairwise and dose-response meta-analyses. RESULTS: A total of 1,037 COPD patients were included in the 20 studies. Based on pairwise comparisons, CT was found to significantly improve 6MWD (MD: 44.08; 95% CrI: 33.35-54.72; SD: 20.85; 95% CrI: 13.29-32.26), VO2max (MD: 1.02; 95% CrI: 0.04-2.00; SD: 0.91; 95% CrI: 0.23-2.12), LP 1RM (MD: 30.53; 95% CrI: 3.38-57.71; SD: 2.52; 95% CrI: 0.04-15.19), CP 1RM (MD: 12.20; 95% CrI: 2.77-21.59; SD: 2.44; 95% CrI: 0.05-10.71), and SGRQ score (MD: -8.65; 95% CrI: -10.79 to -6.51; SD: 5.04; 95% CrI: 2.52-8.99). However, no significant improvement was observed in FVC, FEV1, and FEV1/FVC. Additionally, a nonlinear dose-response relationship was observed between CT and 6MWD, with the optimal dose identified as 1,220 MET-min/week (MD = 24.83; 95% CrI: 14.96-34.70). CONCLUSIONS: CT was found to significantly improve exercise capacity and quality of life in COPD patients, while showing limited effects on pulmonary function indicators. Moreover, a nonlinear dose-response relationship was identified between CT and 6MWD, with the most pronounced effects observed at a weekly dose of 1,220 MET-min. SYSTEMATIC REVIEW REGISTRATION: https://www.crd.york.ac.uk/prospero/, CRD42025630487.

OBJECTIVE: This meta-analysis aimed to evaluate the effects of high-intensity interval training (HIIT) on aerobic capacity, athletic performance, and body composition in martial arts athletes. METHODS: A systematic search was conducted in multiple databases, including PubMed, MEDLINE, Web of Science, CNKI, ProQuest and SciELO, following PRISMA guidelines. Fourteen randomized controlled trials (RCTs) involving 348 participants were included. The inclusion criteria focused on martial arts athletes undergoing HIIT, with outcome measures including aerobic capacity (HRmax, VO2max), athletic performance (strength, agility, speed), and body composition (muscle mass, body fat percentage, body weight). Data were analyzed using a random-effects model to calculate standardized mean differences (SMD). RESULTS: The findings demonstrated that HIIT significantly improved aerobic capacity, athletic performance, and body composition in martial arts athletes. Improvements in aerobic capacity were primarily reflected in VO2max (SMD = 1.04, 95% CI [0.74, 1.33], I 2 = 16.3%, p = 0.284). With respect to athletic performance, significant improvements were observed in lower-limb muscular power (SMD = 0.33, 95% CI [0.02, 0.64], I 2 = 48%, p = 0.017), agility (SMD = -0.45, 95% CI [-0.79, -0.11], I 2 = 0%, p = 0.922), and speed (SMD = -0.45, 95% CI [-0.79, -0.11], I2 = 0%, p = 0.922). Regarding body composition, the primary improvement was observed in percent body fat (SMD = -0.51, 95% CI [-0.92, -0.09], I 2 = 0%, p = 1.000). However, no significant improvements were found in HRmax, skeletal muscle mass, or body weight. CONCLUSION: HIIT represents an effective training modality for martial arts athletes, and future studies should focus on long-term, large-sample randomized controlled trials to further clarify differential effects across subgroups and training modalities, as well as to explore optimal strategies for integrating HIIT with martial arts-specific training.

RATIONALE: Individuals with type 1 diabetes mellitus (T1DM) may present with hypertension. Aerobic exercise could induce post-exercise hypotension. However, the clinical and ambulatory blood pressure responses may vary depending on the exercise prescription. OBJECTIVE: To verify the acute and chronic effect on blood pressure after different aerobic exercise intervals in type-1 diabetics. METHODS: A systematic review following the PRISMA protocol in Pubmed, Scielo, and Medline databases. The TESTEX scale was used to assess the methodological study quality (n = 6). Participants (control group): 35 adolescents and 51 adults (their own control). Acutely: No statistical post-exercise hypotension was found among the studies with clinical analysis, except one for adults performing interval exercise. Additionally, descriptively, three studies shown reduced mean values (∼0.1-10 mmHg in systolic pressure) after 20 or 30 min for adults. A single ambulatory analysis with T1DM adolescents showed a variation of ∼1 mmHg in systolic and diastolic after 24h and the daytime: 118 ± 10 and 71 ± 7 and nighttime mean: 112 ± 11 and 64 ± 9 mmHg (P > 0.05). Chronically: A single study with moderate intensity continuous aerobic training (60 % VO2max) reduced ∼5.8 mmHg in systolic and ∼3 mmHg in diastolic after 12 weeks in T1DM adolescents. CONCLUSION: A single moderate-intensity continuous aerobic session does not promote statistical post-exercise hypotension in adolescents but interval exercise could reduce in males with T1DM adults. However, 12 weeks of continuous aerobic training may reduce SBP significantly for adolescents. Future research should compare blood pressure responses among interval, intermittent, and continuous aerobic exercises in different T1DM ages.

BACKGROUND: Chronic heart failure (CHF) is a common clinical syndrome characterized by reduced exercise capacity, diminished quality of life (QoL), and unfavorable cardiovascular outcomes. Conventional cardiac rehabilitation often requires moderate-to-high-intensity exercise, which may be tolerated poorly by many CHF patients. Low-intensity mind-body interventions, such as traditional Chinese exercises (TCEs), are potentially more suitable; however, the evidence from existing studies is fragmented and sometimes inconsistent. Thus, this study aimed to conduct an umbrella review of systematic reviews (SRs) and meta-analyses (MAs) to evaluate the effectiveness of TCEs in improving exercise capacity, QoL, and cardiovascular function in patients with CHF. METHODS: An umbrella review of SRs/MAs was conducted by searching English and Chinese databases without language limits and focusing on randomized controlled trials (RCTs) that assessed the additional benefit of TCEs in individuals with CHF. Methodological quality was appraised using the A Measurement Tool to Assess Systematic Reviews 2 (AMSTAR 2) checklist and the Risk of Bias in Systematic Reviews (ROBIS) instrument. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system was utilized to quantify the certainty of evidence. Individual trial data were retrieved, and re-meta-analyses were performed using standard statistical procedures, with publication bias assessed via Egger's test. RESULTS: A total of 15 SRs/MAs were included, encompassing 65 original trials. Our re-meta-analysis indicated that TCEs were associated with substantially longer 6-minute walk test (6-MWT) values, improved QoL measured by the Minnesota Living with Heart Failure Questionnaire (MLHFQ), higher left ventricular ejection fraction (LVEF), reduced B-type natriuretic peptide (BNP) levels, and enhanced maximal oxygen consumption (VO2max). Baduanjin exhibited a particularly robust effect on lowering N-terminal pro-B-type natriuretic peptide (NT-proBNP) concentrations, while Yijinjing yielded comparatively greater improvements in VO2max. Nonetheless, limitations such as suboptimal methodological quality and overlappin

PURPOSE: This meta-analysis evaluated the effects of exercise combined with intermittent fasting (EX + IF) on body composition, cardiometabolic health, and muscle performance in adults and examined potential moderators. (2) PubMed, Web of Science, Embase, and the Cochrane Library were searched, and reference lists of eligible studies were screened. Effect sizes were calculated as Hedges'g. A three-level random-effects model was fitted using the metafor package in R, with moderation and meta-regression analyses conducted to identify influential factors. RESULTS: Sixty-five randomized controlled trials (RCTs) including 3,293 participants (18-75 years) were included; 42% were overweight/obese and 11% were trained individuals. Compared with control conditions (exercise alone, intermittent fasting alone, or neither), EX + IF significantly reduced body mass, body mass index, body fat percentage, fat mass, waist circumference, and visceral fat, with no significant effects on fat-free mass or lean body mass. For cardiometabolic outcomes, EX + IF reduced total cholesterol, triglycerides, low-density lipoprotein cholesterol, and interleukin-6; improved fasting blood glucose, fasting insulin, and homeostasis model assessment of insulin resistance (HOMA-IR); and modestly increased VO2max. Multivariable meta-regression indicated maximal effects with 45-60 min per session, 4 sessions/week (230-300 min/week), over 14-30 weeks (cumulative training time 7,463-8,592 min). CONCLUSION: EX + IF improves body composition in adults, benefits selected lipid and glycemic markers, and enhances cardiorespiratory fitness. Based on current evidence, it may be particularly suitable for middle-aged adults with overweight/obesity whose primary goals are weight loss and improved insulin resistance (45-60 min/session, 4 sessions/week, for ≥14 weeks). SYSTEMATIC REVIEW REGISTRATION: https://www.crd.york.ac.uk/PROSPERO/view/CRD420251131430.

BACKGROUND: To systematically evaluate the effects of high-intensity interval training (HIIT) on cardiorespiratory fitness and physical function in middle-aged and older women. METHODS: PubMed, Web of Science, and Scopus were searched from inception to November 2025. Randomized controlled trials comparing HIIT with control interventions in middle-aged and older women were included. Random-effects meta-analyses were performed. Primary outcomes were maximal or peak oxygen uptake (VO2max/VO2peak) and physical or functional performance measures. RESULTS: Nineteen randomized controlled trials were included. Meta-analysis showed that HIIT significantly improved VO2max compared with control interventions (SMD = 1.20, 95% CI 0.86-1.54, I2 = 31%), with high certainty of evidence. No significant effect was observed for VO2peak (SMD = 0.23, 95% CI -0.23 to 0.69). HIIT did not significantly improve muscle strength (SMD = -0.17, 95% CI -1.04 to 0.70), though strength assessments were not always specific to the muscle groups trained, flexibility, or sit-to-stand performance. Walking ability showed a borderline significant improvement (SMD = 0.49, 95% CI 0.00-0.97), with very low certainty of evidence. Subgroup analyses indicated consistent VO2max improvements across age groups, body mass status, and intervention durations. CONCLUSION: HIIT significantly improves cardiorespiratory fitness in middle-aged and older women but shows limited effects on physical function. HIIT alone is insufficient to comprehensively improve functional performance. SYSTEMATIC REVIEW REGISTRATION: https://www.crd.york.ac.uk/PROSPERO/view/CRD420251272861.

BACKGROUND: Physical inactivity is a critical factor exacerbating obstructive sleep apnea (OSA) and its associated comorbidities. Previous evidence has largely relied on subjective questionnaires, leading to a lack of definitive evidence based on objective measurements. This study aimed to systematically evaluate the effects of digital health interventions (DHIs) on objective physical activity, body composition, and sleep parameters in OSA patients, while further exploring the efficacy differences between active intervention and passive monitoring modes. METHODS: A systematic search was conducted across five major databases (including PubMed and Embase) and registration platforms up to November 19, 2025. Only randomized controlled trials (RCTs) that assessed physical activity using objective tools were included. Bias was evaluated using the Cochrane Risk of Bias Tool 2.0 (RoB 2.0), and the quality of evidence was graded using the GRADE system. Statistical analyses utilized random-effects models to calculate Mean Differences (MD) and 95% Confidence Intervals (CI). Subgroup analyses were performed based on a refined classification of intervention modes, accounting for interaction patterns, theoretical foundations, and the application of behavior change techniques (BCTs). RESULTS: A total of seven randomized controlled trials involving 693 patients were included. Overall meta-analyses revealed no statistically significant differences between digital interventions and standard care in increasing daily steps (MD = 86.94, P = 0.85), reducing body mass index (P = 0.74), improving the Apnea-Hypopnea Index (P = 0.31), or alleviating somnolence (P = 0.15). However, telerehabilitation-based interventions significantly improved peak oxygen uptake [MD = 342.41 ml/min, 95% CI (38.05, 646.77)]. Exploratory subgroup analyses and individual study data suggested that active intervention modes characterized by synchronous interaction or theory-driven protocols showed a greater tendency for weight loss compared to passive monitoring and significantly increased absolute step counts during the intervention period (P = 0.02). The overall quality of evidence for the primary outcomes wa

BACKGROUND/OBJECTIVES: While traditional sports nutrition emphasizes high carbohydrate intake for endurance athletes, trained athletes may achieve metabolic adaptation to low-carbohydrate and ketogenic diets with maintained or improved performance outcomes. This systematic review and meta-analysis synthesize evidence on the effects of low-carbohydrate (≤130 g·day-1 or ≤25% total energy) and ketogenic (<50 g·day-1 or <10% total energy) diets on aerobic performance variables in trained athletes. METHODS: A comprehensive search of five electronic databases (PubMed, SCOPUS, Web of Science, SPORTDiscus, and Cochrane Central Register of Controlled Trials) identified 33 aerobic-focused studies meeting comprehensive inclusion criteria. Selected studies examined trained athletes (≥6 months structured training, age 18-45 years) randomized to low-carbohydrate, ketogenic, or high-carbohydrate control conditions with outcome data on aerobic performance variables (VO2max, time trial performance, time to exhaustion, and exercise economy) and metabolic markers (fat oxidation and substrate utilization). Quality assessment employed Newcastle-Ottawa Scale methodology. RESULTS: Maximal aerobic capacity (VO2max) was preserved in 50.0% of studies, with 11.1% documenting improvements. Submaximal exercise economy showed the greatest sensitivity, with 50.0% documenting impaired efficiency. Time to exhaustion demonstrated context-dependent effects, with 69.2% maintaining performance. All 30 studies measuring fat oxidation demonstrated consistent increases (+28% to +200%). Critically, temporal analysis identified a 1-week adaptation threshold: studies measuring outcomes within ≤7 days documented performance impairment, while studies measuring at >1 week consistently demonstrated maintained or improved performance. CONCLUSIONS: Low-carbohydrate diets reliably induce metabolic adaptation characterized by dramatically increased fat oxidative capacity. However, aerobic performance responses are nuanced, with preserved maximal aerobic power, transient submaximal efficiency impairments, and context-dependent endurance effects. Adaptation involves initial acute-phase decrements (≤7 days) followe

Update of doi: 10.1002/14651858.CD013617. RATIONALE: The estimated global cost of inactivity is USD (US dollar) 53.8 billion. Exercise is a low-cost, effective, and accessible intervention that can reduce cardiovascular disease risk in sedentary populations. However, nearly one-third of adults do not meet the levels of physical activity recommended by the World Health Organization (WHO). WHO guidelines do not include advice for people who wish to undertake high-intensity interval training (HIIT), because it is unclear whether HIIT is an efficacious and acceptable method for sedentary populations to reduce their risk of cardiometabolic syndrome. As lack of time is the most frequently cited barrier to exercise, and HIIT requires a lower time commitment than moderate-intensity continuous training (MICT), this topic warrants a high-quality, non-biased exploration of the literature. OBJECTIVES: To assess the benefits and harms of high-intensity interval training (HIIT) on cardiometabolic health in healthy, sedentary adults. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, Web of Science Core Collection (SCI-Expanded, SSCi, CPCI-S), and two trial registries up to 13 October 2025. ELIGIBILITY CRITERIA: We included randomised control trials (RCTs) that compared HIIT with a non-exercise control (comparison 1) or with MICT (comparison 2) over four weeks or longer in healthy adults (aged 18-64 years) who were sedentary at baseline. We excluded studies of athletes, as we were interested in the benefits of HIIT for public health, not for performance. We also excluded studies of people with overweight (body mass index (BMI) 25-29.9 kg/m²) or obesity (BMI ≥ 30 kg/m²) who were recruited as a result of a medical event or diagnosis. OUTCOMES: Our main outcomes were cardiorespiratory fitness (measured as maximum oxygen consumption (VO2max) or peak oxygen consumption), systolic blood pressure, waist circumference, waist-to-hip ratio, all-cause mortality, circulating triglycerides, and adverse events. RISK OF BIAS: We used the Cochrane risk of bias tool (Rob 2) to assess the risk of bias in the RCTs. SYNTHESIS METHODS: We synthesised results for each outcome using a random-eff

BACKGROUND: Low-volume high-intensity interval training (LVHIIT) is known to improve cardiometabolic health; however, the potential additive effects of combining LVHIIT with inspiratory muscle training (IMT) in reducing the severity of metabolic syndrome (MetS) have not been fully explored. This study aimed to evaluate the effects of 8 weeks of IMT combined with LVHIIT on cardiorespiratory fitness, MetS parameters, and respiratory muscle function in individuals with MetS. METHODS: This randomized, controlled, double-blind trial included 38 adults with MetS, aged 42 to 60 years, who were randomly assigned to 3 groups: LVHIIT (n = 12), LVHIIT + IMT (n = 14), and control (n = 12). The primary outcome was the change in maximal oxygen consumption (VO2max) after 8 weeks. Secondary outcomes included MetS z-score, anthropometric measures, metabolic blood markers, and respiratory muscle strength and endurance. All outcomes were assessed at baseline and after the 8-week intervention. RESULTS: The mean age of participants was 50 ± 5 years, and 67% were women. Significant group × time interactions were observed for VO2max, oxygen uptake efficiency slope, heart rate recovery at 1 minute, waist circumference, hip circumference, visceral fat ratio, fasting plasma glucose, glycosylated hemoglobin A1c, and MetS z-score (P < .05). Both LVHIIT and LVHIIT + IMT groups showed significant improvements in VO2max (P < .001). Respiratory muscle strength and endurance increased significantly only in the LVHIIT + IMT group (P < .001). CONCLUSION: Eight weeks of LVHIIT combined with IMT led to improvements in cardiorespiratory fitness, respiratory muscle function, and key MetS components, including MetS z-score. Integrating IMT into LVHIIT may be an effective, clinically feasible, and time-efficient approach to improve cardiometabolic health in individuals with MetS in cardiac rehabilitation.

This randomized controlled trial examined the effects of a 10-week high-intensity interval training (HIIT) program on physiological and hematological outcomes in 28 adolescent girls with overweight or obesity. Participants were randomly assigned to a HIIT group or a control group. The HIIT protocol comprised 4 sets of 6 × 15-s bouts at 90%-105% of maximal aerobic speed (MAS), interspersed with 15-s active recovery at 50% MAS, performed three times per week. Significant group×time interactions were observed for body composition, aerobic capacity, maximal heart rate (HRmax), erythrocytes, hemoglobin, hematocrit, creatine kinase (CK), and lactate dehydrogenase (LDH). Between-group comparisons showed greater improvements in body mass, body fat, waist circumference, MAS, estimated VO2max, and plasma volume in the HIIT group compared with controls, though not all differences reached statistical significance. Within-group analysis in the HIIT group revealed reductions in body mass (p < 0.001, d = 0.37), body fat (p = 0.001, d = 0.78), waist circumference (p < 0.001, d = 0.54), HRmax (p = 0.020, d = 0.88), erythrocytes (p = 0.007, d = 0.46), hemoglobin (p = 0.019, d = 0.84), hematocrit (p = 0.004, d = 0.34), CK (p = 0.049, d = 0.29), and LDH (p = 0.032, d = 0.41), alongside increases in MAS (p = 0.007, d = 0.64) and estimated VO2max (p = 0.007, d = 0.64). Plasma volume variation was also higher in the HIIT group. Overall, a 10-week HIIT intervention enhanced body composition, plasma volume, and cardiorespiratory fitness, while reducing markers of muscular and metabolic stress. These results indicate that HIIT is a feasible and effective approach for improving physiological and metabolic health in adolescent girls with overweight or obesity, supporting its potential as a targeted exercise strategy in this population. © 2026 The Author(s). European Journal of Sport Science published by Wiley‐VCH GmbH on behalf of European College of Sport Science.

PURPOSE: High-intensity interval training (HIIT) is a well-established exercise method, known for its effectiveness in improving various aspects of fitness. This study aimed to assess the effect of five distinct HIIT protocols, including Small Sided Games Long Interval (SSG(LI)), Long Interval (LI), Small Sided Games Short Interval (SSG(SI)), Short Interval (SI), and Sprint Interval Training (SIT), on aerobic, agility, vertical jump performance, sprinting abilities, and heart rate variability (HRV) in amateur soccer players. METHODS: Forty participants were randomly assigned to one of five training groups, and a four-week training intervention was conducted. The pre- and post-training assessments included measurements of maximal oxygen uptake (VO2max), anaerobic power, reactive agility, vertical jump height, sprint times, and HRV parameters. RESULTS: Results showed that all training groups demonstrated significant improvements in VO2max. Reactive agility performance significantly improved in the SSG(LI), SSG(SI), SI, and SIT groups, whereas no significant changes were observed in sprint times or anaerobic power. Leg-specific vertical jump performance showed significant improvements in the right and left legs. HRV parameters showed variable responses to the training protocols. Significant main effects of Time were observed for LF (F = 3.592, p = 0.016, ηp 2 = 0.310) and low frequency/high frequency (LF/HF) ratio (F = 5.699, p = 0.023, ηp 2 = 0.151), indicating overall changes across participants from pre- to post-training. CONCLUSIONS: These findings underscore the adaptability of HIIT and its association with improvements in aerobic endurance, agility, and leg-specific vertical jumping capabilities across different training forms, while acknowledging that causation cannot be definitively established due to the quasi-experimental design. ©2026 Karabıyık et al.

Exercise may lower Alzheimer's Disease and Related Dementia (ADRD) risk. While insulin has been proposed to benefit cognition, the effect of exercise on neuronal insulin signaling in humans is unclear. PURPOSE: We tested the hypothesis that a single bout of aerobic exercise would raise insulin signaling mediators from plasma-derived neuronal extracellular vesicles (nEVs). METHODS: Fifteen sedentary adults with obesity (12F; ~56y; ~31 kg/m2) completed an evening rest and acute exercise condition (70% maximal oxygen consumption (VO2max)) in a randomized, counterbalanced order. Following an overnight fast, plasma was collected for analysis of nEV insulin signaling biomarkers before and after intranasal insulin spray (INI, 40 IU) as well as 60 min following a 75 g oral glucose tolerance test (OGTT). Plasma glucose and insulin were also measured at 30 and 60 min during the OGTT, and total area under the curve (tAUC) was calculated. RESULTS: Exercise tended to lower glucose tAUC0-150min (p = 0.08, d = 0.50), independent of insulin tAUC0-150min (p = 0.99, d = 0.00). Exercise increased pIR-Tyr1162/Tyr1163 (p = 0.05, η2 = 0.05), pIRS-1-Ser636 (p = 0.02, η2 = 0.07), pAkt-Ser473 (p = 0.03, η2 = 0.06), and pTSC2-Ser939 (p = 0.01, η2 = 0.08) with medium effect sizes across blood draws, compared with the resting condition. Exercise also raised fasting and decreased pp70S6K-Thr412 before and after the OGTT, compared with increased levels after rest during the OGTT (p = 0.02, η2 = 0.10). Exercise had no effect on other insulin signaling proteins (e.g., pmTOR-Ser2448, pGSK3β-Ser9, etc.). CONCLUSIONS: A single bout of aerobic exercise increases some nEV-associated insulin signaling phosphoproteins in people with cardiometabolic risk. Additional work is warranted to determine if changes in brain insulin signaling translate to lower ADRD risk. CLINICAL TRIALS REGISTRATION: NCT05853913. © 2026 The Author(s). Comprehensive Physiology published by Wiley Periodicals LLC on behalf of American Physiological Society. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.

BACKGROUND: Accessibility barriers contribute to low participation in center-based cardiac rehabilitation. We developed an innovative, comprehensive, dual-phase telerehabilitation program to address this gap (Smartphone Cardiac Rehabilitation, Assisted Self-Management; SCRAM). OBJECTIVE: The study aimed to determine the effectiveness of SCRAM for increasing maximal aerobic exercise capacity (VO2max). METHODS: A multicenter, parallel 2-arm randomized controlled trial recruited clinically stable adults (aged ≥18 y) with diagnosed coronary heart disease at 3 hospitals in Victoria, Australia (Melbourne, Geelong, and Bendigo) from 2018 to 2021. Participants were randomized (1:1), stratified by sex and study site, to receive SCRAM plus usual cardiovascular care (intervention) or usual cardiovascular care alone (control). SCRAM provided 24 weeks of remote exercise supervision, coaching, and behavior change support via smartphone. Usual cardiovascular care included standard medical care and advice to seek a referral to center-based cardiac rehabilitation, which was heavily impacted during the COVID-19 pandemic. Due to the nature of the treatments, participants were not blinded to allocation; primary outcome assessors and biostatisticians were blinded. The primary outcome was VO2max at 24 weeks, analyzed on the principle of intention-to-treat, using linear regression adjusted for baseline and stratification factors on multiple imputed data. RESULTS: Recruitment and data collection were heavily impacted by COVID-19, although SCRAM delivery was sustained throughout. Of 220 required participants, only 123 (56%) were recruited and randomized (intervention n=63, control n=60); 45% (55/123) had missing VO2max at 24 weeks-largely due to enforced COVID-19 restrictions. Mean VO2max at 24 weeks favored SCRAM (26.10, SD 10.72 mL/kg/min) over control (24.65, SD 7.87 mL/kg/min), but the difference was not statistically significant (mean difference=1.61 mL/kg/min, 95% CI -1.38 to 4.61, P=.28). Among secondary outcomes, patients receiving SCRAM had lower diastolic blood pressure at 24 weeks (mean difference=-5.54 mm Hg, 95% CI -10.01 to -1.06). All reported adverse events (control n=6,

Metformin reduces hyperglycemia and cardiovascular disease risk. However, no study has determined if metformin alters blood pressure and/or aortic waveforms in an exercise intensity dependent manner. We tested if metformin alters blood pressure and aortic waveforms before and during insulin-stimulation following low and high intensity exercise training. In a double-blind, placebo controlled trial, participants were randomized to low intensity exercise plus placebo (∼55% VO2max 5 days/week, LoEx+PL, n = 22) or metformin (2000 mg/day, LoEx+Met, n = 21) and high intensity exercise plus placebo (∼85% VO2max 5 days/week, HiEx+PL, n = 24) or metformin (HiEx+Met, n = 24) for 16 weeks. Carotid-femoral pulse wave velocity (cfPWV) was assessed to determine arterial stiffness. A 120 min euglycemic-hyperinsulinemic clamp (40mU/m2/min, 90 mg/dL) was conducted to assess peripheral and central blood pressures as well as aortic waveforms via applanation tonometry. Inflammatory measures (e.g., hs-CRP, IL-8, MMP-1 and MMP-7) along with fitness (VO2max) and body composition (DXA) were also analyzed. While LoEx+PL tended to decrease cfPWV (p = 0.051), HiEx+Met reduced fasting peripheral diastolic blood pressure (pDBP; p < 0.05) and all treatments except HiEx+Met increased fasting central pulse pressure (p < 0.05). Upon insulin-stimulation, pDBP and reflection magnitude increased while pulse pressure amplification (PPA) decreased after LoEx+Met and HiEx+Met compared with LoEx+PL and HiEx+PL independent of exercise intensity (all, p < 0.05). Interestingly, fasting MMP-1 (p < 0.05) and MMP-7 (p = 0.063) tended to be higher after Met compared with PL, independent of exercise intensity. In conclusion, metformin altered blood pressure and aortic waveform adaptations in relation to inflammation following exercise training in adults at risk for metabolic syndrome. Trial Registration: NCT03355469. © 2026 The Author(s). The Journal of Clinical Hypertension published by Wiley Periodicals LLC.

PURPOSE: This study aimed to compare the effects of three slide-board training modalities-two high-intensity interval training protocols (HIIT1: 3 min work/2 min rest; HIIT2: 4 min work/1 min rest) and one moderate-intensity continuous training protocol (MICT: 20 min at 70% HRmax)-on aerobic and anaerobic capacities in young speed skaters. METHODS: Twenty-seven youth speed skaters (15 males, 12 females) were randomly assigned to HIIT1, HIIT2, or MICT groups (n = 9 each). All participants completed a 4-week intervention (3 sessions/week) using a slide-board simulator. Aerobic capacity was assessed via maximal oxygen uptake (VO2max) and peak aerobic power output (Pmax) using an incremental cycle test. Anaerobic performance was evaluated with a 30-second Wingate test, including relative peak power (RPP), relative mean power (RMP), and fatigue index (FI). Pre- and post-test data were analyzed using two-way repeated measures ANOVA and paired t-tests. RESULTS: Both HIIT1 and HIIT2 significantly improved VO2max, RPP, and RMP, and reduced FI (p < 0.05), whereas MICT showed no significant changes in any variable. HIIT2 demonstrated greater improvements in Pmax and anaerobic power metrics compared to HIIT1, though intergroup differences were not statistically significant. HIIT1 appeared to enhance fatigue resistance more effectively. CONCLUSION: Slide-board HIIT is an effective short-term training method for enhancing aerobic fitness and anaerobic power in youth speed skaters. HIIT2 (4 + 1 structure) may be more beneficial for sprinters requiring explosive power, while HIIT1 (3 + 2 structure) may suit middle- to long-distance skaters focusing on endurance and fatigue resistance. MICT alone appears insufficient to induce meaningful physiological adaptations in a 4-week period. These findings support the use of structure-specific HIIT protocols for sport-specific conditioning in speed skating. Copyright: © 2026 Zhang et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Background: Structured lipids, composed of re-esterified triacylglycerols containing eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and medium-chain fatty acids, may influence metabolism and endurance performance. This trial aimed to evaluate the effects of eight weeks of structured lipid supplementation on substrate utilization, erythrocyte fatty acid content, and endurance performance in healthy untrained men. Methods: In a double-blind, placebo-controlled, randomized design, 36 participants (18 per group) received either structured lipids or placebo supplementation for eight weeks. Pre- and post-supplementation assessments included maximal oxygen uptake, time to exhaustion, substrate oxidation during exercise at 65% VO2max, and erythrocyte membrane fatty acid content. Non-parametric statistical methods were used to analyze within- and between-group differences. Results: After supplementation, the structured lipids group showed statistically significant within-group changes in substrate utilization, including lower respiratory exchange ratio and higher percentage fat oxidation, total fat oxidation, and mean fat oxidation rate. Statistically significant increases were also observed in erythrocyte EPA + DHA content and time to exhaustion. Compared with the placebo group, the structured lipids group showed statistically significant post-intervention differences in substrate oxidation, erythrocyte EPA + DHA levels, and time to exhaustion. Conclusions: Eight weeks of structured lipid supplementation increased erythrocyte membrane EPA and DHA and enhanced fat oxidation during moderate-intensity exercise in untrained men. Although endurance performance improved, the change was within natural variability and showed substantial interindividual differences. Further rigorously controlled studies are needed to determine whether these metabolic adaptations yield meaningful functional benefits.

Sleep is a fundamental aspect of physiological and psychological functioning, and the beneficial effect of exercise on sleep quality and quantity, depending on training modality, remains underexplored. This study compared the effects of high-intensity interval training (HIIT) versus a moderate-intensity continuous training (MICT) regime on sleep quality. Twenty-five participants (sixteen men, nine women) were randomly assigned to 8-week HIIT or MICT programs. Anthropometric data, blood pressure, and maximal exercise tests (VO2max, lactate, heart rate) were conducted one week before and after training. Sleep quality was evaluated daily through self-reported perception and duration and via the Pittsburgh Sleep Quality Index (PSQI) at baseline, one week, and two weeks post-intervention. Data were analyzed in SPSS version 29 using repeated-measures ANOVA. PSQI scores improved significantly over time (p = 0.013), regardless of modality, with no significant group or interaction effects. Cardiorespiratory fitness improved for all participants, with significant gains in VO2max (p = 0.009), maximal aerobic speed (p < 0.001), and reduced maximal heart rate (HIIT: p = 0.003; MICT: p = 0.021). Sleep perception showed no significant change during training (p = 0.063), with a slight improvement trend. In conclusion, exercise training improves sleep quality regardless of modality. Running three sessions per week for eight weeks enhances both aerobic and cardiorespiratory fitness, along with sleep quality. Physical activity is therefore an effective non-pharmacological strategy to improve sleep.

This study examined effects of two moderate-intensity aerobic exercise prescriptions on inflammatory cytokines and oxidative stress biomarkers in middle-aged obese Hispanic females. Fifty-four subjects were randomly assigned to a lower-moderate intensity group (55% VO2max, LT, n = 18), an upper-moderate intensity group (70% VO2max, HT, n = 19), or a non-exercise control group (CON, n = 17). Blood samples collected before and after a 12-week intervention were analyzed for tumor necrosis factor-alpha (TNF-α), adiponectin, C-reactive protein (CRP), total antioxidant status (TAS), and 8-hydroxy-2'-deoxyguanosine (8-OHdG). Body fat percentage (%BF) and visceral adipose tissue (VAT) were assessed using dual-energy X-ray absorptiometry. TNF-α significantly decreased in both LT (p = 0.004) and HT (p < 0.001). Significant increases in adiponectin (p = 0.001) and reductions in CRP (p < 0.001) were observed within the HT, whereas these changes were not significant within the LT. TAS significantly increased in both exercise groups (p < 0.001), and 8-OHdG significantly decreased in the HT (p < 0.001) and LT (p = 0.002). Both LT and HT demonstrated significant reductions in %BF (p < 0.001) and VAT (p < 0.05), with no significant changes in CON. Results indicate that moderate-intensity aerobic exercise improves inflammatory and oxidative stress profiles when total exercise volume is matched, regardless of differences in exercise intensity within the moderate range. Although post-intervention differences between groups were not statistically significant, the observation that CRP, adiponectin, and 8-OHdG changed significantly only within HT suggests that exercise intensity may influence biomarker responsiveness and warrants further investigation.

Background/Objectives: Masters athletes are adults aged ≥40 who compete in sport, exhibiting superior physical function and healthier aging than their sedentary peers. However, even highly trained masters athletes experience age-related performance declines. Women masters athletes represent a growing yet understudied population who may face unique physiological challenges. This scoping review synthesizes literature from 1984 to 2024, examining the impact of age and menopause on determinants of endurance performance in women masters athletes. Methods: Following JBI scoping review methodology, six databases were searched (Medline, Embase, Central, CINAHL, SPORTdiscus, Scopus). Studies were evaluated for population characteristics, methodological approaches, and physiological determinants of performance (i.e., aerobic capacity, lactate kinetics, and exercise economy). Results: Twenty-nine studies were included. Most (n = 28) assessed aerobic capacity, reporting declines between 0.36 and 0.84 mL·kg-1·min-1·year-1 (0.5-2.4%·year-1). These reductions were primarily associated with decreased cardiac output followed by changes in body composition. Training volume emerged as a predictor of aerobic capacity, but the effects of menopause were unclear. Findings on lactate kinetics and exercise economy were mixed but preliminary research indicated that lactate threshold relative to VO2max generally increased, peak lactate remained stable and energy cost increased with age. Fitness and health characteristics among women athletes differed from sedentary populations, emphasizing the need for athlete-specific data to support training and health decisions. Conclusions: Aging is associated with decreased aerobic capacity and variable changes in lactate kinetics and exercise economy. While training volume may attenuate performance decrements, the impact of menopause remains uncertain, underscoring the need for longitudinal research to better support this growing segment of the population.

Over the past decade, randomized controlled trials have established that, after eating either a low-carbohydrate, high-fat or a high-carbohydrate, low-fat diet for 4-6 wk, trained athletes performed equally well during a maximum oxygen consumption (VO2max) test; during 5 and 1.6 km laboratory treadmill time trials; during a 6 × 800 m interval repetition session; and during a prolonged cycling test to exhaustion at 70%VO2max. Indeed, during the 6 × 800 m interval repetition session, some subjects achieved the highest rates of fat oxidation (2 g/min) ever reported in humans; whereas ingestion of 10 g carbohydrate/h improved prolonged cycling test performance by 22%, equally following either diet. These data establish that muscle glycogen is not an obligatory fuel for exercise. Rather, exercise-induced hypoglycemia due to depletion of glucose in the small glucose pool in the liver and bloodstream, prevented by minimal carbohydrate ingestion during exercise, is the main metabolic contributor to premature fatigue during more prolonged submaximal exercise.

Most older adults spend most of their waking hours sedentary, a behavior associated with adverse metabolic outcomes, including reduced metabolic flexibility. While interrupting sedentary time has shown benefits, its impact on metabolic flexibility remains unexplored. This study investigates whether different doses of timed interruptions of sedentary behaviors with light activity elicit acute adaptations in metabolic flexibility in older adults. Twelve sedentary older adults, free of any chronic conditions, (9W/3 M; 72.3 ± 4.8 years; BMI: 26.8 ± 3.6 kg/m²) completed three randomized 8-hour sedentary conditions: noBreaks, Break30 (3-minute breaks every 30 min), and Break60 (6-minute breaks every 60 min). Breaks involved treadmill walking at light intensity (i.e. 30% of VO2max reserve). Metabolic flexibility was determined by combining hourly measurements of respiratory exchange ratio (RER) and plasma insulin levels (T0-T8). Meals (consumed after T0 and T4) were standardized for the day before and during the experiment day. Mixed linear models included fixed effects (condition, time and condition x time) and random effects (time, condition, participant). Break30 exhibited a greater variance in RER throughout the day compared to noBreak whereas no difference was observed for insulin. Significant condition-by-time interactions were observed for RER at T4 (noBreak=0.83±0.04, Break30=0.86±0.04, Break60=0.83±0.04, p = 0.035) and T7 (noBreak=0.87±0.04, Break30=0.90±0.05, Break60=0.89±0.05; p = 0.002). A significant interaction was also observed for non‑esterified fatty acid concentrations at T5 (noBreak=0.251 ± 0.042 mmol/L, Break30=0.393 ± 0.042 mmol/L, Break60=0.373 ± 0.042 mmol/L; p = 0.041). Compared with prolonged sedentary behavior, interrupting sitting every 30 or 60 min appears to induce acute alteration in substrate oxidation. Further studies are needed to confirm these results and to evaluate potential long‑term adaptations.

PURPOSE: Hypohydration of ≥ 2% body mass loss (BML) can impair cycling performance in the heat; however, it remains unclear whether this is primarily due to the body water deficit itself or the concomitant, typically observed increase in serum sodium concentration (S[Na+]). To disentangle these effects, we examined the performance effects of 60% (60FR) vs. 80% (80FR) fluid replacement, designed to achieve > 2% vs < 2% BML, with personalised sodium prescription targeting condition-matched S[Na+]. METHODS: Eleven male cyclists (35 ± 6 years, VȮ2max 58 ± 5 ml·kg-1·min-1) completed two trials, consisting of 180 min cycling (90% LT1, 32 °C, 50% humidity), followed by a work-matched time-trial (TT). Participants received either 60% or 80% of projected fluid losses, along with sodium supplementation aiming to maintain S[Na+] where dilution of S[Na+] was predicted. Outcomes included BML, S[Na+], plasma volume change (∆PV), rectal (Tre) and skin (Tsk) temperatures, whole-body sweat rate (WBSR), and TT performance. RESULTS: BML was greater in 60FR at all time-points (P < 0.01), whereas S[[Na+] remained stable across both trials (P = 0.07). In 80FR, ∆PV was smaller during the preload, Tre was lower from 120 min onwards and Tsk and WBSR were higher during the TT compared to 60FR (all P < 0.05). TT completion time was 8 ± 10% faster in 80FR (1793 ± 174 vs 1968 ± 246 s, P = 0.02). CONCLUSION: Fluid replacement resulting in BML > 2% impairs thermoregulation and cycling performance in the heat, compared to maintaining BML < 2%, despite no differences in S[Na+]. © 2026. The Author(s).

INTRODUCTION: Exercise is known to exert systemic effects associated with improved cardiovascular fitness and epigenetic modifications. However, the relationships between systemic epigenetic markers and physical fitness indicators remain insufficiently characterized. METHODS: In the present study, the Illumina MethylationEPIC array (~730,000 CpG sites) was used to investigate associations between blood DNA methylation and key continuous fitness indicators-estimated VO₂max, grip strength, and vertical jump height-in a cohort of healthy adults. Epigenome-wide association analyses were adjusted for age, sex, estimated blood cell composition, and multiple testing. RESULTS: No significant single-CpG associations were identified after rigorous adjustment. However, when participants were stratified into groups based on age- and sex-specific VO₂max norms, three CpG sites demonstrated differential methylation at a false discovery rate threshold (FDR < 0.05). These included cg21308111 in TNFRSF10A and cg17890932 in USP24, both showing higher methylation in lower-fitness groups, and an intergenic CpG site (cg02967877) exhibiting the opposite pattern. Region-based analyses further identified several differentially methylated regions (DMRs) between fitness groups. DISCUSSION: These findings suggest that variation in cardiorespiratory fitness may be associated with subtle alterations in blood DNA methylation, particularly at loci related to metabolic regulation, inflammatory pathways, and intercellular communication. These findings shouldbe considered hypothesis-generating and require confirmation in larger, independent cohorts and, ideally, in longitudinal or intervention studies to elucidate more directly how changes in physical fitness relate to changes in DNA methylation patterns.

AIMS: Despite significant medical advances in recent decades, cardiopulmonary fitness decreases faster in youth with congenital heart disease (CHD) than in healthy peers, resulting in impaired health-related quality of life (HRQoL) and increased cardiovascular risk. Apart from cardiac rehabilitation, non-pharmacological preventive interventions have been scarcely evaluated in this population. Sophrology, a mind-body method involving dynamic relaxation in full awareness, breathing exercises, and imagination, has demonstrated benefits for mental health and well-being. This multicenter randomized controlled trial evaluated the impact of a remote sophrology program on cardiopulmonary fitness and HRQoL in youth with CHD. METHODS AND RESULTS: A total of 200 13-to-25-year-old CHD patients were randomly assigned to either the intervention (i.e., eight remote individual sophrology sessions), or the standard of care. The primary outcome was the change in maximum oxygen uptake (VO2max) measured by cardiopulmonary exercise testing from baseline to 12 months. Secondary outcomes included HRQoL and mental health assessments. No significant VO2max group difference was observed (mean difference -0.11; 95% CI -2.02, 1.79; p=0.91). The HRQoL "Mental Component Summary", "Mental Health" and "Vitality" SF-36 scores increased in the young adult intervention subgroup (18-25 years) by 8.98 (95% CI 2.73; 15.23, p<0.01, effect size 0.84), 14.49 (95% CI 3.17; 25.81, p=0.01, effect size 0.74), and 15.75 (95% CI 3.97; 27.53, p<0.01, effect size 0.78) points, respectively. CONCLUSION: The remote sophrology program did not improve cardiopulmonary fitness, but significantly enhanced HRQoL in young adults with CHD. Integrating mind-body practices into preventive cardiology programs should be further evaluated. Registration: Clinicaltrials.gov (NCT03999320). © The Author(s) 2026. Published by Oxford University Press on behalf of the European Society of Cardiology.

The reduced availability of oxygen under hypoxic conditions makes it necessary to adjust training intensity by reducing the workload and modifying exercise zones. The aim of this study was to evaluate the effects of normobaric hypoxia of varying severity (H2000: FiO2 = 16.5%, ~2000 m; H3000: FiO2 = 14.5%, ~3000 m) on physiological variables associated with the maximal lactate steady state (MLSS) in trained cyclists, including the work rate (WRMLSS), oxygen uptake (VO2MLSS), minute ventilation (V̇EMLSS), and the heart rate (HRMLSS). Sixteen trained male cyclists (age: 30 ± 5 years; body height: 180.5 ± 8.0 cm; body mass: 75.2 ± 9.0 kg; body fat content: 10.2 ± 2.0%; VO2 max: 57.0 ± 6.0 ml/kg/min) performed incremental and constant-load exercise tests under normoxic (N) and hypoxic (H2000 and H3000) conditions to determine the MLSS. Exposure to H2000 and H3000 significantly reduced the WRMLSS by 9.3% and 18.5%, respectively, as well as VO2MLSS by 7.2% and 17% compared with normoxia (p < 0.05), while the HRMLSS remained unchanged. SpO2 showed a statistically significant (p < 0.05) drop between N and H2000 (-10.61%), as well as N and H3000 (-16.43%). Blood lactate concentration at the 30th min of MLSS exercise was significantly (p < 0.05) higher under both H2000 (+36%) and H3000 (+34%) conditions compared to N. These findings indicate that acute normobaric hypoxia equivalent to 2000 and 3000 m significantly impairs the ability to sustain exercise at MLSS intensity. It is recommended that MLSS power be reduced by ~10% at 2000 m and by ~20% at 3000 m, while HR values remain unchanged under both conditions. Copyright: © Academy of Physical Education in Katowice.

Hydration status modulates both exercise performance capacity and exercise tolerance. This study aimed to examine within-trial relationships among core temperature (Tc), ratings of perceived exertion (RPE), and thirst during moderate continuous cycling, and to test whether baseline hydration status would moderate these associations. Thirty trained men (34.7 ± 6.1 years; VO2max 48.8 ± 5.8 ml·kg⁻1·min⁻1) completed up to 120 min of cycling at 50% Wmax under thermoneutral conditions. Participants were randomized to an experimental group receiving structured hydration counseling (EXP, n = 16) or a control group following habitual fluid intake (CON, n = 14). Hydration status was verified via urine specific gravity; Tc (CORE heat-flux sensor), the heart rate, RPE (0-10), and thirst (0¬-10) were recorded every 15 min. Analyses included repeated-measures tests, Spearman correlations, and ANCOVA adjusting for baselines and VO2max. Tc rose from rest and tended to plateau by ~60-75 min, whereas RPE and thirst increased throughout. Hydration status predicted higher RPE (partial η2 = 0.41, p < 0.001) with Tc not independently significant (p = 0.81); VO2max was not a significant predictor, although the effect estimate suggested an inverse association with RPE (p = 0.058). For thirst, hydration status remained significant (partial η2 = 0.27-0.50, p ≤ 0.005). Comparing the two groups, the CON group showed greater increases in RPE (ΔRPE mean +0.23 ± 0.05, p < 0.001; ΔRPE peak +0.53 ± 0.10, p < 0.001) and thirst (ΔThirst mean +0.23±0.04, p < 0.001). EXP participants more often completed the 120-min trial (75.0% vs. 28.6%; χ2 = 10.57, p = 0.014). Perceptual coupling was strong (ΔRPE-ΔThirst r_s≈0.84), with ΔRPE inversely related to VO2max and ΔTc modestly. Starting exercise euhydrated reduces perceived effort and thirst during prolonged, thermoneutral cycling, while Tc per se adds little explanatory power for RPE after adjustment. Simple field markers (thirst, heart rate) can flag emerging strain, particularly in less fit individuals. Copyright: © Academy of Physical Education in Katowice.

Background: Vitamin D deficiency has been implicated in disturbances of glucose and lipid metabolism, particularly in occupational groups with limited sunlight exposure. This study aimed to examine the association between serum 25-hydroxyvitamin D [25(OH)D] concentrations and markers of carbohydrate and lipid metabolism in salt mine workers. Methods: This cross-sectional study involved 62 male salt miners (aged 25-63 years), stratified by work depth (surface, ≤750 m, and >750 m). Anthropometric characteristics, body composition, cardiorespiratory fitness (VO2max), and biochemical parameters were assessed. Blood analyses included fasting glucose, insulin, lipid profile, TSH, and 25(OH)D. Insulin resistance was evaluated via the HOMA-IR index. Results: The cohort exhibited a high prevalence of overweight and obesity (mean BMI > 28 kg/m2). Significant differences in VO2max were observed between groups (p < 0.05). Elevated fasting glucose (>100 mg/dL) was observed in 47% of participants, and 22% presented HOMA-IR values > 2.5. In the regression model, vitamin D supplementation was the strongest predictor of 25(OH)D levels, explaining 25.5% of its variance. The addition of HDL cholesterol increased the explained variance to 35.6%, whereas HOMA-IR contributed an additional 3.9% (p = 0.094). Conclusions: In salt miners, insufficient vitamin D status coexists with excess adiposity and impaired glucose homeostasis. Serum 25(OH)D was more strongly associated with supplementation and HDL-C than with HOMA-IR. These findings suggest that monitoring vitamin D status is relevant in the occupational health evaluation of this group.

BACKGROUND: Fatigue during intensive exercise is closely associated with metabolic inefficiency and lactate accumulation. While Icariin, a natural flavonoid, has demonstrated potential in enhancing exercise performance, the precise cellular mechanisms governing its anti-fatigue effects remain incompletely elucidated. METHODS: We employed an integrated approach combining in vivo exercise models in C57BL/6 mice with in vitro C2C12 myotube systems. Mice received Icariin supplementation (50 or 100 mg/kg) for 4 weeks before comprehensive physiological assessments. Cellular studies utilized caffeine stimulation, transcriptomic profiling, and metabolic analyses. Molecular mechanisms were investigated through western blotting, immunofluorescence, and genetic knockdown approaches. RESULTS: Icariin supplementation dose-dependently enhanced exercise performance, evidenced by increased maximal oxygen consumption (VO2max) and prolonged exhaustive running time. This improvement was accompanied by reduced blood lactate accumulation, skeletal muscle hypertrophy, and a shift toward oxidative fiber types. In C2C12 myotubes, Icariin directly attenuated lactate production by suppressing LDH activity and reprogramming cellular metabolism toward oxidative phosphorylation. Transcriptomic analysis revealed significant enrichment of mitophagy pathways, which was validated by enhanced mitophagic flux and improved mitochondrial membrane potential. Mechanistically, we identified TFEB as the key transcriptional regulator mediating Icariin's effects, evidenced by its dephosphorylation, nuclear translocation, and transactivation of mitophagic genes. Crucially, TFEB knockdown completely abolished Icariin-induced mitophagy, metabolic improvements, and lactate reduction. CONCLUSION: Our findings establish a comprehensive mechanistic pathway wherein Icariin activates TFEB to drive mitophagic clearance of dysfunctional mitochondria, thereby optimizing mitochondrial function and shifting energy metabolism toward oxidative phosphorylation. This TFEB-mitophagy axis represents the core mechanism through which Icariin enhances exercise performance and metabolic efficiency, providing novel insights into