Search Results (115)

Background: Beetroot-derived nitrate supplementation is a widely studied nutritional strategy to enhance athletic performance. Although ergogenic benefits have been reported in recreational and moderately trained individuals, evidence for highly trained and elite athletes remains inconsistent. Objectives: This scoping review aimed to map and synthesize evidence from randomized controlled trials (RCTs) investigating the effects of beetroot-derived nitrate supplementation on performance, recovery, and physiological outcomes in highly trained and elite athletes. Methods: The review followed the Joanna Briggs Institute methodology and PRISMA-ScR guidelines. Literature searches were conducted in PubMed, Scopus, and Web of Science. Eligible studies included RCTs involving McKay Tier 3–5 athletes and evaluating beetroot-derived nitrate supplementation as a standalone intervention. Results: Thirty-one RCTs met the inclusion criteria, representing athletes from a wide range of sports. Supplementation protocols varied substantially, with nitrate doses ranging from 4 to 19.5 mmol·day⁻¹ (248–1209 mg·day⁻¹) and durations from acute administration to 15 days. Positive effects were most frequently reported for cycling time-trial performance, Yo-Yo intermittent recovery performance, anaerobic power, neuromuscular performance, exercise tolerance, and recovery. In contrast, findings for endurance performance, sport-specific skills, oxygen consumption, and perceptual responses were inconsistent despite marked increases in nitrate and nitrite bioavailability. The outcomes seemed to depend on dosage, duration, sport type, and athletes’ training status. Conclusions: Beetroot-derived nitrate supplementation may enhance performance in highly trained and elite athletes, particularly during high-intensity and anaerobic activities. However, the effects are inconsistent, underscoring the need for further research to establish optimal supplementation strategies and evaluate long-term efficacy in elite sporting populations. Full article

Background/Objectives: Beetroot juice (BRJ), a dietary nitrate source, may enhance high-intensity intermittent exercise, but its effects on single- and repeated-sprint performance remain unclear. This systematic review and meta-analysis aimed to evaluate the effects of BRJ supplementation on sprint-related performance and neuromuscular, perceptual, and physiological outcomes. Methods: PubMed, Scopus, and Web of Science were searched for trials published from 2014 to June 2026. Eligible studies compared BRJ with placebo or control in healthy adults aged 18–40 years. The review followed PRISMA guidelines. Methodological quality and risk of bias were assessed using the PEDro scale and Cochrane RoB 2 tool. Evidence certainty was assessed using GRADE. Standardized mean differences (SMDs) with 95% confidence intervals (CIs) were calculated. Results: Twenty-three randomized trials involving 401 participants were included, and 21 contributed to the meta-analysis. BRJ improved time to peak power in four Wingate-based studies (SMD = −0.92, 95% CI: −1.29 to −0.54, p < 0.001) and handgrip strength (SMD = 0.40, 95% CI: 0.05 to 0.74, p = 0.027). No significant effects were observed for countermovement jump, peak or mean power, 10 m or 20 m sprint performance, perceived exertion, heart rate, or blood lactate. Sex did not significantly moderate the effects, although female data were limited. Certainty was low for most outcomes and very low for 20 m sprint performance and blood lactate. Conclusions: BRJ may improve time to peak power and handgrip strength; however, low- to very-low-certainty evidence does not support its routine use to enhance short-distance or repeated-sprint performance. Full article

Background: Recovery between repeated high-intensity efforts is essential to limit fatigue and performance decline in soccer. This study examined the effects of cold water immersion (CWI), foam rolling (FR), and passive recovery during a 15 min interval between two 5 m shuttle run tests (5mSRTs) on physical performance, perceptual responses, and biochemical markers of muscle damage and inflammation. Methods: Fifteen soccer players (age: 22.6 ± 2.03 years) completed passive recovery, FR, and lower-body CWI at 15 °C in a randomized crossover design. Creatine kinase (CK), lactate dehydrogenase (LDH), C-reactive protein (CRP), aspartate transaminase (AST), delayed onset muscle soreness (DOMS), and belief questionnaire scores were assessed before the first 5mSRT and immediately after, and then 24 h, 48 h, and 72 h after the second 5mSRT. Results: Between the first and the second 5mSRT, TD remained unchanged following CWI (p = 0.21), whereas significant decreases were observed following passive recovery (p = 0.025) and FR (p = 0.028). Also, BD decreased after passive recovery (p = 0.03). At 48 h, CWI elicited lower CK (p = 0.01) and LDH (p = 0.003) than passive recovery, whereas FR resulted in lower AST concentrations (p = 0.01). Participants reported higher belief scores following CWI and FR than passive recovery throughout the recovery period (p < 0.05). No between-condition differences were observed for FI, PD, RPE, DOMS, or CRP (all p > 0.05). Conclusions: CWI may help preserve repeated-running performance and attenuate selected markers of muscle damage following repeated high-intensity intermittent exercise in soccer players, whereas FR demonstrated only limited physiological effects. Full article

Background: Aerobic capacity and respiratory efficiency are critical determinants of performance in elite female football, characterized by repeated high-intensity efforts and rapid recovery demands. Halotherapy, involving the inhalation of dry salt aerosol, has been shown to improve pulmonary health; however, its effects on exercise-related outcomes in athletic populations remain insufficiently investigated. This study aimed to examine the effects of a 12-week post-training halotherapy intervention on respiratory muscle strength, pulmonary function, and aerobic performance in elite female football players. Methods: Twenty-eight elite female football players competing in the Turkish Women’s First League were randomly assigned to a halotherapy group (HG, n = 14) or a control group (CG, n = 14). Both groups completed an identical preseason training program, while the HG additionally performed 45 min halotherapy sessions three times per week in a controlled halochamber. Pre- and post-intervention assessments included maximal inspiratory and expiratory pressures (MIP, MEP), spirometric parameters (FVC, FEV₁, PEF, MVV), and maximal oxygen uptake (VO₂max) estimated using the Yo-Yo Intermittent Recovery Test Level 1 (Yo-Yo IRT1), along with total distance covered. A 2 × 2 mixed-model ANOVA was used to assess time and group × time interaction effects. Results: Significant group × time interactions were observed for MIP, MEP, VO₂max, FEV₁, PEF, MVV, and Yo-Yo IRT1 performance (p < 0.05), with large effect sizes (ηp² = 0.269–0.924), favoring the halotherapy group. Forced vital capacity (FVC) increased over time in both groups (p = 0.141), with no significant interaction effect. Changes in the control group were comparatively smaller across most outcomes. Conclusion: Post-training halotherapy was associated with improvements in respiratory muscle strength, ventilatory function, aerobic capacity, and intermittent running performance in elite female football players. These findings suggest that halotherapy may be considered as a complementary, non-invasive strategy to support respiratory and aerobic adaptations. Further research is required to confirm these findings and to clarify the underlying physiological mechanisms. Trial registration: NCT07406386; 6 February 2026. Full article

Background: Contemporary adults face fragmented schedules, sedentary digital work, cognitive load, logistical barriers, and unstable routines that can make conventional session-based exercise difficult to sustain. Exercise snacks, vigorous intermittent lifestyle physical activity (VILPA), movement breaks, low-volume high-intensity interval training (HIIT), workplace exercise, and digitally mediated physical activity may reflect a broader redesign of exercise for real-world lifestyles. Objective: To develop a conceptual framework for lifestyle-congruent exercise models: approaches that intentionally modify dose, timing, setting, delivery, autonomy, or routine integration to reduce lifestyle-related friction while preserving a plausible physiological or behavioral stimulus. Methods: This evidence-based narrative review purposively identified sources through targeted searches, citation tracking, and manual verification across exercise science, sedentary behavior, workplace health, behavioral medicine, and digital health. Sources were selected for conceptual relevance, model-family representation, evidence-type diversity, and contribution to framework development, and then charted by model family, population, context, exercise architecture, delivery, outcomes, and implementation features. No systematic protocol, formal risk-of-bias assessment, or certainty grading were applied. Results: Thirty-one sources informed the framework. Five design logics were identified: dose compression, temporal distribution, routine embedding, sedentary substitution, and delivery mediation. These logics show that brief or time-efficient models are not interchangeable; they differ in intentionality, context, behavioral demand, safety considerations, implementation logic, and dominant friction addressed. Conclusions: Lifestyle-congruent exercise models are complementary strategies, not replacements for structured aerobic and muscle-strengthening exercise. Their value lies in matching exercise architecture to lifestyle-related friction while supporting progression toward guideline-consistent activity. Future research should test safety, equity, scalability, and long-term maintenance across diverse populations. Full article

Background: Performing and maintaining high-altitude cardiopulmonary resuscitation (CPR) could pose a significant physical challenge for rescuers. The objective of this study is to analyse the effects of reducing the oxygen fraction at altitudes of 3000 m and 5000 m above sea level (asl), with and without conditioning to hypoxia, on the quality of resuscitation performed in adults. Methods: An analytical before–after study in which 56 students with a Degree in Nursing between 18 and 30 years old perform 10 min of resuscitation on a mannequin at different altitudes (670, 3000 and 5000 m asl) will be carried out. Subsequently completing an intermittent hypoxia conditioning programme, the participants will perform the resuscitation manoeuvres at previously referenced altitudes. Sociodemographics, CPR quality, self-perception CPR, adequate anthropometric data, physical condition, blood tests, oxygenation in muscular tissue, biceps, brachii and erector spinae, subjective perception of effort, anxiety levels and quality of resuscitation will be measured in all participants at different altitudes. Discussion: Although CPR is a submaximal effort manoeuvre, it is subject to being performed by anyone without motor disabilities. Our study will also provide evidence as to whether this characteristic continues to hold true in a hostile environment such as medium and high altitudes. Our study aims to demonstrate that the improvement in physical performance and recovery capacity induced by intermittent hypoxia conditioning programmes increases the quality of CPR in prolonged cardiac arrests and in adverse conditions, such as at high altitudes. The proposed study will contribute as a novelty to the estimation of the influence of high altitudes and conditioning on performing basic CPR manoeuvres. If the hypothesis turns out to be true, recommendations about the practice of moderate-intensity physical exercise could be incorporated into the CPR guidelines as one of the important aspects in the training of rescuers to conduct CPR. Full article

Background/Objectives: Caffeinated chewing gum is a practical, rapidly absorbed ergogenic aid increasingly used in team sports, yet its interaction with different small-sided soccer game (SSG) formats in young male players remains unclear. This study evaluated the effects of acute caffeinated (CAF) chewing gum on psychophysiological responses and kinematic profiles during intermittent (INT) and continuous (CON) 3-a-side SSGs. Methods: Twenty-four young male soccer players (18.4 ± 0.5 years) completed four 3-a-side SSG sessions separated by 48 h in a randomized, double-blind, placebo (PLA)-controlled, crossover design (CAF-INT, PLA-INT, CAF-CON, PLA-CON). Participants chewed 300 mg of CAF or PLA gum for 5 min, with mastication completed 5 min before warm-up session. The heart rates and kinematic profiles were recorded during the SSGs, and the ratings of perceived exertion (RPE), exercise enjoyment scale (EES), and visual analogue scale (VAS) to perceived mental fatigue (MF) were assessed post-game. Results: Compared with the PLA, the CAF increased the heart rate responses (HR), EES, total distance (TD), player load (PL), acceleration (ACC), and distances covered in selected speed zones (from Z0 to Z5), while reducing the RPE and MF. Significant format × supplementation interactions indicated that CAF-induced changes in high-intensity kinematic outcomes (TD, PL, ACC, Z2–Z5) and HR responses (HR_mean, HR_max) were generally greater in INT, whereas CAF-induced increases in low-intensity running distances (Z0 and Z1) and %HR_max were more pronounced in the CON format (all p < 0.05 for the reported effects; ${\eta }_p^2$ = 0.16–0.93 for CAF main effects [large effects]). The EES improvements were more pronounced in the CON format, whereas the MF and RPE reductions were more pronounced in the INT format. Conclusions: CAF chewing gum may be a practical acute strategy for modulating psychophysiological responses and kinematic profiles during SSGs, with the effects depending partly on the game format. Full article

High-intensity intermittent exercise can acutely alter circulating cytokines, but findings are heterogeneous. The aim was to systematically synthesize acute blood cytokine responses after a single high-intensity intermittent exercise session in humans. PubMed, Scopus, and Web of Science Core Collection, plus reference screening. Eligibility criteria included original human studies measuring serum or plasma cytokines pre-exercise and at least one post-exercise time point after high-intensity intermittent exercise. Sampling was mapped to prespecified recovery windows. Risk of bias was assessed using RoB 2 (randomized trials) and the Joanna Briggs Institute quasi-experimental tool. Narrative synthesis was used. From 2077 records, 45 studies were included. Most protocols used cycling or treadmill modalities, and sampling clustered in the immediate and early recovery windows. Interleukin 6 most consistently increased after exercise, whereas tumor necrosis factor alpha, interleukin 10, and other mediators showed mixed or context-dependent changes. Risk of bias was commonly rated as some concerns, with frequent limitations in pre-analytical control and reporting. Across included studies, high-intensity intermittent exercise tended to elicit a short-lived myokine-dominant inflammatory signal, characterized primarily by an increase in circulating interleukin 6, most often detected in the immediate and early recovery windows. Conflicting findings for tumor necrosis factor alpha, interleukin 10, redox-related outcomes, and less frequently measured mediators were best explained by a small set of dominant moderators: post-exercise sampling window, exercise dose/internal load, participant metabolic and training phenotype, and pre-analytical or assay-related heterogeneity. Registration: Open Science Framework (osf.io/wspr6; 17 February 2026). Full article

Rising ambient temperatures and the increasing frequency of training and competition in hot climates have made heat stress a major challenge in football. Under such conditions, players experience greater cardiovascular and thermoregulatory strain, faster glycogen use, higher perceived exertion, and progressive impairment in repeated high-intensity actions and decision-making. These responses have intensified interest in nutritional strategies that might complement heat acclimation, hydration/electrolyte planning, cooling practices, and recovery management. This narrative review critically synthesizes current evidence on nutritional interventions that may be relevant to football performed in the heat, with emphasis on hydration and electrolyte replacement, carbohydrate–protein strategies, taurine, branched-chain amino acids (BCAAs), creatine, menthol, antioxidant- and nitrate-related approaches, and selected multi-ingredient products. Across the available literature, hydration/electrolyte planning and carbohydrate–protein feeding remain the practical foundation, menthol appears most consistently useful for perceptual cooling, creatine seems safe and potentially helpful for repeated-sprint support, and taurine is promising but still supported by relatively few trials. By contrast, evidence for BCAAs, antioxidants, nitrates, and caffeine as stand-alone heat strategies, as well as for many compound supplements, remains inconsistent, context-specific, or too indirect for strong football-specific endorsement. Overall, the evidence base remains heterogeneous in study quality, protocol design, exercise mode, and sport specificity. A substantial proportion of the available data is derived from cycling, endurance, or laboratory heat-exercise models rather than football-specific trials. Accordingly, any practical recommendation should be interpreted cautiously and embedded within broader heat-management strategies. Future work should prioritize ecologically valid randomized controlled trials in football or football-like intermittent protocols, with transparent reporting of dose, timing, perceptual outcomes, and match-relevant performance measures. Full article

Background/Objectives: Although creatine monohydrate is widely recognized as an effective ergogenic aid in strength and power sports, its role in endurance and mixed-sport disciplines remains less clearly established. This scoping review aimed to map the current evidence regarding the effects of creatine supplementation on performance, recovery-related outcomes, and body composition in endurance and mixed-sport contexts. Methods: A scoping review of randomized controlled trials published between 1996 and 2025 was conducted. Eligible studies evaluated creatine supplementation in endurance and mixed-sport contexts, including both sport-specific and broader exercise populations when the exercise protocol, testing model, or outcomes were relevant to endurance or mixed-sport performance, recovery, or body composition. A total of 38 studies met the inclusion criteria. Outcomes were categorized into exercise performance, biochemical markers related to recovery and exercise stress, and body composition parameters. Results: Creatine supplementation was most often associated with reported favorable changes in repeated-sprint performance and high-intensity power output, particularly during intermittent, sprint-based, or power-endurance tasks. Several studies reported favorable changes in sprint performance, peak power, or total work output relative to placebo or baseline values in cycling, swimming, rowing, and canoeing/kayaking protocols, although findings were not uniform across studies and not all favorable within-group changes were placebo-superior. Some studies also reported favorable changes in end-phase sprint capacity during prolonged exercise. Findings related to recovery were less consistent. Selected studies reported reductions in inflammatory markers, including C-reactive protein (CRP) and tumor necrosis factor α (TNF-α), whereas markers of muscle damage showed mixed responses. Most supplementation protocols involved a 5–7-day loading phase of 20 g/day, occasionally followed by a maintenance dose of 2–5 g/day. Small increases in total body mass were commonly observed, while evidence regarding fat-free mass and aerobic outcomes remained limited or inconsistent. Conclusions: Current evidence suggests that creatine supplementation may be most relevant in selected endurance and mixed-sport contexts involving repeated high-intensity efforts, sprint finishes, or power-endurance demands, rather than for endurance performance broadly. In contrast, evidence for recovery-related biochemical responses, body composition changes, and aerobic adaptations remains equivocal. Further well-controlled, sport- or context-specific, and field-based studies are needed to better clarify the role of creatine in endurance and mixed-sport exercise. Full article

This study examined whether acute exercise performed within individualized physiological intensity zones affects multidimensional soccer shooting performance. Twenty male collegiate soccer players completed a Yo-Yo Intermittent Recovery Test Level 1 with portable gas analysis to determine the ventilatory threshold (VT) and respiratory compensation point (RCP). Three individualized zones were defined: Low (<VT), Moderate (VT–RCP), and High (>RCP). In a randomized design, players completed three 3 min shuttle-running bouts, each followed immediately by the 356 Soccer Shooting Test. Ball velocity (BV), shooting accuracy (SA), and shooting quality (SQ) were analyzed using repeated-measures ANOVA. Exercise condition significantly affected SA (p = 0.013) and SQ (p = 0.007), but not BV (p = 0.216). Bonferroni-adjusted comparisons showed that SA and SQ were lower in High than in Low, whereas no pairwise BV comparison reached significance. A sensitivity analysis using all ten recorded attempts rather than the original best-seven scoring approach showed an overall condition effect for BV without a significant pairwise comparison, retained overall effects for SA and SQ, and showed that the Low–High contrast remained robust only for SQ. Baseline comparisons were not significant. These findings indicate condition-specific shooting responses, with the clearest evidence for lower SQ after High compared with Low, supportive evidence for lower SA, and no significant primary condition effect for BV. Full article

Background/Objectives: Regular physical exercise is strongly recommended for individuals with type 1 diabetes mellitus (T1DM) because of its beneficial effects on cardiovascular fitness, insulin sensitivity, metabolic control, and overall health. Nevertheless, participation in physical activity remains limited, largely due to the fear of exercise-induced hypoglycemia and glycemic instability. Glycemic responses to exercise in T1DM are influenced by the interaction between exercise modality, circulating insulin levels, nutritional status, and diabetes technologies. Continuous aerobic exercise, resistance training, high-intensity interval exercise, and mixed intermittent activities elicit distinct metabolic and hormonal responses, resulting in heterogeneous glycemic trajectories. This narrative review aimed to provide a clinically oriented synthesis of the physiological mechanisms underlying exercise-related glycemic fluctuations in T1DM and to discuss integrated insulin- and carbohydrate-based strategies to support safer participation in physical activity in the context of modern diabetes technologies. Methods: A structured narrative review was conducted using PubMed/MEDLINE, Scopus, and complementary searches in Google Scholar to identify experimental studies, observational studies, systematic reviews, consensus statements, and clinical guidelines focused on exercise-related glycemic responses in individuals with T1DM. Only articles published in English were considered. Evidence was selected and synthesized according to relevance to exercise modality, insulin therapy strategies, carbohydrate management, and diabetes technologies, including continuous glucose monitoring, continuous subcutaneous insulin infusion, and automated insulin delivery systems. The final narrative synthesis was based on 44 selected studies, reviews, consensus statements, and guidance documents considered most relevant to the objectives of this narrative review. Results: Available evidence indicates that continuous moderate-intensity aerobic exercise is most consistently associated with progressive glucose declines and increased risk of hypoglycemia, particularly when performed in the presence of elevated insulin on board. In contrast, resistance exercise and short-duration high-intensity or anaerobic exercise more frequently induce stable glycemia or transient hyperglycemia through adrenergic stimulation and increased hepatic glucose output. Mixed and intermittent exercise modalities often produce more variable responses depending on exercise sequencing, nutritional status, and insulin exposure. Across studies, integrated adjustment of basal and prandial insulin doses together with individualized carbohydrate supplementation emerged as the most effective strategy to reduce exercise-related glycemic instability. Continuous glucose monitoring and insulin pump technologies improved glucose trend awareness and management flexibility; however, physical exercise remains a challenging condition for current automated insulin delivery algorithms and still requires active user-driven decision-making. Conclusions: Exercise management in T1DM should be based on an individualized interpretation of exercise modality, glucose trends, insulin exposure, and nutritional context rather than on fixed glucose thresholds alone. Combining anticipatory insulin adjustments, tailored carbohydrate strategies, and appropriate use of diabetes technologies may substantially reduce glycemic variability and improve confidence toward physical activity participation. Structured education and individualized clinical guidance remain essential to translate physiological knowledge into effective real-world exercise management. Full article

Objective: This study aimed to investigate the acute effects of intermittent high-intensity badminton court exercise on cardiac autonomic modulation in male non-elite badminton players. Methods: This study employed a single-arm, repeated-measures experimental design, recruiting 25 healthy male collegiate badminton players. Participants completed five sets of high-intensity intermittent court tests until exhaustion, followed by calculation of stress index (SI), time-domain (RMSSD and SDNN), and frequency-domain (LF, HF, and LF/HF ratio) parameters at rest using a certified heart rate variability (HRV) analyzer. Repeated-measures ANOVA and effect size (partial η² and Hedges’ g) were used to assess changes and recovery trends of HRV parameters across time points: pre-test, immediate, 15 min, 24 h, and 48 h post-exercise. Results: (1) Stress index: The overall temporal trend showed statistical significance (p < 0.001, partial η² = 0.236, large effect size). Compared to pre-test, immediate and 15 min post-exercise increases were 8.24 (95% CI: 0.63–15.85) and 9.84 (95% CI: 3.07–16.61) respectively, with Hedges’ g values of 0.77 and 0.99 (p < 0.001, large effect sizes). Values returned to pre-test levels at 24 and 48 h with no significant differences (p > 0.05). (2) Time-domain parameters: The overall temporal trend was statistically significant (p < 0.001, partial η² = 0.553 for RMSSD and 0.586 for SDNN, both large effect sizes). Immediate post-exercise decreases in RMSSD and SDNN were 35.44 (95% CI: 21.95, 48.93) and 48.44 (95% CI: 32.49, 64.38) respectively, with Hedges’ g values of 2.31 and 2.78 (p < 0.001, large effect sizes). At 15 min, decreases were 31.64 (17.85, 45.42) and 41.48 (26.23, 56.72) respectively, with Hedges’ g values of 1.99 and 2.25 (p < 0.001, large effect sizes). Values returned to pre-test levels at 24 and 48 h with no significant differences (p > 0.05). (3) Frequency-domain parameters: Compared to pre-test, differences in LF, HF, and LF/HF were not statistically significant at any time point (all p > 0.05). Conclusions: Following high-intensity exercise leading to peripheral fatigue, cardiac autonomic function demonstrates a “suppression–recovery” dynamic pattern: cardiac stress levels increase significantly within 15 min post-exercise, with decreased overall HRV regulatory capacity and strong inhibition of parasympathetic activity; HRV status may return to baseline levels after 24 h. However, the frequency-domain indices of HRV showed no significant changes in response to the acute effects of high-intensity exercise. Full article

Objectives: To determine whether four weeks of Rhodiola rosea (RHO) supplementation improves intermittent exercise performance, post-exercise blood lactate concentrations, and decision-making under fatigue in competitive football players. Methods: Twenty-four male competitive football players completed a randomised, double-blind, placebo-controlled 4-week intervention (RHO vs. placebo). Outcomes included Yo-Yo IR2, repeated-sprint ability (RSA), post-RSA blood lactate (0, 3, 5 min), football-specific technical tests (passing and shooting), a video-based decision-making task (reaction time and accuracy), GPS-derived match running metrics, countermovement jump (CMJ), foot tapping (TAP), and haematological markers. Results: Yo-Yo IR2 performance significantly improved in the RHO group (p = 0.012) and was superior to the placebo group (p = 0.046). For RSA, mean sprint time improved significantly from pre- to post-intervention in the RHO group (p = 0.017), whereas no significant change was observed in the placebo group. Post-intervention, mean sprint time was significantly better in RHO than placebo (p = 0.041), with no between-group difference observed at baseline. Best sprint time showed no between-group difference (p = 0.723). Post-exercise blood lactate concentrations were significantly lower in RHO than placebo at 0, 3, and 5 min (all p < 0.05). Under fatigue, the RHO group demonstrated faster reaction time (p = 0.042) and higher decision accuracy (p = 0.049) than placebo. Additionally, the RHO group showed significant pre- to post-intervention improvements in passing and shooting performance (p < 0.05), with between-group differences observed only for short-pass performance. Match total and high-speed running distances were higher in RHO, accompanied by increases in haemoglobin and haematocrit (p < 0.05). Conclusions: Four weeks of Rhodiola rosea supplementation enhanced high-intensity intermittent performance and decision-making under fatigue, with findings suggesting improved performance maintenance rather than increased peak sprint capacity. Full article

Sedentary behavior contributes to obesity and metabolic dysfunction, yet few interventions individualize exercise intensity using fuel-based metrics such as the respiratory exchange ratio (RER; VCO₂/VO₂). This study investigated the effects of metabolically guided walking combined with whole-food, plant-based nutrition on body composition and metabolic outcomes in sedentary overweight and obese women. Forty-four women mean age 43 years; BMI 30.1 kg·m⁻²) were randomized to low-intensity continuous training (LICT; RER ≈ 0.75), moderate-intensity intermittent training (MIIT; RER ≈ 0.85), or high-intensity continuous training (HICT; RER ≈ 0.95). Following a 2-week dietary lead-in with an individualized ~200 kcal·day⁻¹ energy deficit, participants completed an 8-week RER-guided walking program (5 sessions·week⁻¹; 15–50 min·session⁻¹). Assessments included air-displacement plethysmography (BodPod) body composition, resting metabolic rate and substrate utilization, and oxygen uptake at the first ventilatory threshold (VT1). Data were analyzed using ANCOVA, mixed-factorial ANOVA, and Pearson correlations. Percent body fat decreased significantly across participants (p < 0.0001, η² = 0.827), with MIIT demonstrating the most favorable integrated outcomes. MIIT elicited the largest reductions in total body mass (−11.2%), fat mass (−25.9%), and percent body fat (−17.1%), alongside improvements in VT1 VO₂ (Δ = 1.487 ± 0.895 L·min⁻¹; p = 0.038). Resting respiratory quotient (RQ) declined in LICT and MIIT but increased in HICT, corresponding with increased fat oxidation in LICT and MIIT and reduced fat oxidation in HICT. Changes in RQ were significantly associated with changes in percent body fat (r = 0.316, p = 0.039). Metabolically guided moderate-intensity intermittent walking combined with whole-food, plant-based nutrition produced the most consistent improvements in adiposity, substrate utilization, and submaximal fitness, supporting the public-health feasibility of a community-deliverable, substrate-informed walking prescription. Full article