International journal of sport nutrition and exercise metabolism最新文献

Ramadan-type diurnal fasting, which restricts both food and fluid intake from dawn to sunset, may influence physiological, metabolic, and perceptual responses during high-intensity exercise. However, its acute effects under matched external workload conditions in field-based soccer training remain unclear. This study examined the physiological, neuromuscular, metabolic, and perceptual responses to a matched high-intensity intermittent training session performed under fed and Ramadan-type fasting conditions. Twenty male university-level soccer players completed two counterbalanced sessions. External load was matched using 10-Hz GPS monitoring. Physiological variables, including oxygen uptake, carbon dioxide production, respiratory exchange ratio, minute ventilation, and heart rate, along with blood lactate concentration, session rating of perceived exertion, perceptual scales (thermal discomfort and thirst), neuromuscular performance assessed via countermovement jump height and power, and body mass were measured before and after exercise. External mechanical load did not differ between conditions. Ramadan-type fasting elicited significantly higher minute ventilation, mean and maximal heart rate, and session rating of perceived exertion, whereas carbon dioxide production, respiratory exchange ratio, and peak blood lactate concentration were significantly lower. Oxygen uptake did not differ between conditions. Thermal discomfort and thirst increased from pre- to postexercise in both trials (time effect), with perceived thirst showing a greater increase under fasting conditions (interaction effect). Countermovement jump height and power demonstrated significant pre-to-post reductions (time effect) without condition or interaction effects. Body mass decreased significantly from pre- to postexercise in both trials (time effect), with no condition or interaction effects. These findings indicate that Ramadan-type fasting increases internal physiological and perceptual load during high-intensity intermittent soccer training despite identical external workloads, while neuromuscular performance and exercise-induced body mass loss remain preserved. Practitioners should consider that athletes may experience higher internal strain during fasting-based sessions even when mechanical output is maintained.

This study examined how resistance exercise (RE) volume, a potential key factor in appetite regulation, influences subjective appetite, gut appetite hormones, and energy intake. Eighteen males (aged 21-27 years) completed failure RE (FRE; three sets of failure reps at 70% (at 1 RM), non-FRE (NFRE; 3 × 7 reps at 70% 1 RM), and control (CON) trials. Appetite and acyl-ghrelin, peptide YY, lactate, and glucose were measured pre- and postexercise 0-90 min. Ad libitum meal was provided after exercise. Participants recorded energy intake for the day before, the day of, and the day after each session. The incremental area under the curve (iAUC) for acyl-ghrelin (AG) in the FRE and NFRE were significantly lower than in the CON (p < .001). Peptide YY iAUC and glucose iAUC in the FRE were significantly higher than in the CON (p < .001; p = .003). There was a dose-response for lactate iAUC (FRE > NFRE > CON; p < .001). Appetite iAUC was significantly lower in the FRE than in the CON (p = .012). There were no significant differences in postexercise ad libitum meal and self-reported free-living energy intake between the three sessions (p = .246, p = .226). Acyl-ghrelin was negatively correlated with lactate and positively correlated with overall appetite in both RE sessions. Lactate was negatively correlated with overall appetite in both RE sessions. Moderate-intensity RE with moderate volume-induced temporary appetite suppression, whereas FRE led to prolonged suppression and greater appetite-related hormonal responses, yet neither affected energy intake in young males.

Carbohydrate (CHO), caffeine (CAF), and menthol (MEN) mouth rinses are emerging ergogenic aids that may enhance sports performance without the gastrointestinal risks of ingestion. However, there is limited evidence specifically regarding their effects on high-intensity intermittent exercise (HIIE) performance. This systematic review and meta-analysis aimed to evaluate the effect of mouth rinsing on HIIE performance, specifically focusing on solutions containing CHO, CAF, and/or MEN. A comprehensive literature search was conducted using seven databases through June 2025, following the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist. Twenty randomized crossover studies were included. Overall, our meta-analysis revealed no significant improvement in overall HIIE performance following CHO mouth rinse (standardized mean difference = 0.18; 95% confidence interval [-0.10, 0.46]; p = .21), CAF mouth rinse (standardized mean difference = 0.37; 95% confidence interval [-0.02, 0.75]; p = .06), and CHO + CAF combined mouth rinse (standardized mean difference = -0.19; 95% confidence interval [-0.68, 0.30]; p = .44). Subgroup analysis based on HIIE performance outcomes, including power output, total distance covered, and sprint time, also showed no significant differences for any mouth rinse (p > .05). MEN mouth rinse reported no performance benefits in hot environments, despite an improved cooling sensation. While some individual studies suggested improvements-particularly with low glycogen availability or frequent rinsing-the overall evidence does not support mouth rinsing as an ergogenic strategy for HIIE. Further well-controlled research is needed to define optimal rinse type, timing, frequency, and dietary context for HIIE applications.

Skeletal muscle glycogen depletion is considered one of the key contributing factors toward fatigue and associated performance decrements in soccer. Ensuring adequate carbohydrate availability before and during training and matches is widely advised as a priority for players, and for that reason, carbohydrate-based fueling guidelines for soccer have been developed. However, the lack of female-specific research used to inform the development of these guidelines raises important questions regarding their applicability for female soccer players. This review critically appraises the likelihood of there being between-sex differences in carbohydrate requirements for soccer performance. Males and females exhibit differences in substrate utilization during exercise, substrate storage capacity, relative quantities of fat and fat-free mass, and running demands of soccer match-play, but the extent to which these differences translate into practically meaningful differences in carbohydrate requirements for soccer performance remains unclear. Based on current evidence, we consider it premature to suggest that female players will require sex-specific guidelines in relation to carbohydrate-based fueling strategies for performance in soccer. However, intervention studies in female players investigating carbohydrate-based fueling strategies before and during soccer match-play or simulated soccer protocols are warranted.

Novel cycling disciplines, such as cycling Esports and gravel racing, have recently seen a surge in participation, media visibility, and the establishment of international competitions. However, there is limited peer-reviewed research into the specific physiological and nutritional demands required for success in these disciplines. As part of the larger UCI Sports Nutrition project, this review utilizes qualitative interviews to gain a deeper understanding of the nutrition practices of athletes currently competing in these events. We contextualize these responses by describing contemporary nutrition strategies and evidence-based practice adopted from other disciplines, along with practical application considering the distinct challenges presented by these new and emerging cycling disciplines. Key issues for these disciplines include in race nutrition targeting the specific needs of the event, noting that the logistics of consuming food and drinks in gravel racing and Esports are different to other modalities such as road cycling. Optimization of body mass is a shared concern particularly in Esports in which the requirement for a prerace "weigh-in" may lead to practices usually seen in weight division sports. Finally, a number of supplements including caffeine, creatine, buffering agents, and hyperhydrating agents such as glycerol may enhance performance when used according to evidence-based protocols.

The use of sports foods and supplements has become ubiquitous among cyclists of all disciplines in order to meet energy and nutrient targets and to improve performance and recovery outcomes. This review will provide an overview of the different types of products and the rationale for their use, while highlighting key considerations surrounding the safety and anti-doping risks that supplements pose among athletes. A summary of supplements with a strong evidence base (caffeine, creatine, sodium bicarbonate, beta-alanine, dietary nitrate, and glycerol) and emerging supplements popularized within cycling (exogenous ketones) is also provided, outlining accepted protocols for use, timing, and potential ergogenic effects or side effects.

Elite cyclists frequently train and compete in extreme environments, such as heat, and cold conditions that are becoming more common due to climate change. Altitude training, aimed at preparing athletes for high-altitude events, is widely employed to enhance subsequent sea-level performance. Similarly, heat training has proven to have a similar transfer effect, in addition to the essential acclimatization effects, relevant for performance in hot conditions. Exposure to these challenging environments increases physiological stress raising energy and carbohydrate oxidation rates, and affecting overall performance. This Union Cycliste Internationale (UCI) consensus on nutrition for cycling addresses the nutritional challenges associated with extreme environmental conditions and explores tailored nutrition and hydration strategies to mitigate their effects. The review examines how heat, cold, and altitude affect hydration, energy expenditure, and metabolism, with associated macro- and micronutrient considerations, in cyclists. It discusses practical strategies for managing fluid balance, carbohydrate intake, and micronutrient and electrolyte supplementation and the use of ergogenic aids in supporting adaptation to environmental stresses. This review provides evidence-based nutrition and fluid recommendations for optimizing cycling performance and fostering adaptation in extreme environments. It offers practical guidance on nutrition and hydration strategies before, during, and after training and competition, helping cyclists maintain peak performance while navigating the unique challenges posed by these conditions.

As a group, cyclists tend to have lower bone mass compared with other athletes, and nonathlete controls which may have negative consequences for fracture risk and longer term bone health. There are several cycling-specific factors that may contribute to this finding. These include, the low-impact, repetitive load nature of cycling which provides limited stimulus for bone metabolism; metabolic perturbations that occur following prolonged cycling that may lead to a transient increase in the rate of bone resorption; and nutritional factors, including low energy availability or nutrient inadequacy. Furthermore, many endurance cyclists are naturally lean and light, which may result from both genetic predisposition and long-term training adaptations. In turn, they may also have lower bone mass. None of these factors stand out as the primary cause of the low bone mass reported in cyclists but, instead, may combine to create a "perfect storm" to challenge cyclist bone health. Given these multiple potential challenges to bone health, a multifaceted approach may be required to combat them. On an individual level, nutritional strategies, including ensuring adequate energy, carbohydrate, protein, calcium, vitamin D, and other important micronutrients may be key to protecting cyclist bone health. Integrating brief bouts of high-impact loading within the training regimen and ensuring adequate sleep and recovery are also recommended. The onus should not remain solely on the individual, however, and cycling teams and organizational bodies have a key role to play in providing screening and educational strategies to support cyclists bone health.

Implementing a high-quality approach to the methodological classification and control of the ovarian hormone status of female participants in research is challenging and complex. These complexities have likely hindered the formulation of robust conclusions regarding the effects of the ovarian hormones (estrogen and progesterone) on sport science outcomes. We have therefore developed practical study design tools and resources to aid researchers in the pursuit of high-quality research in women. Specifically, this paper presents a tiered framework outlining varying levels of methodological classification and control of participant ovarian hormone status in exercise and performance studies involving postpubertal to premenopausal female participants. To support implementation, we also provide resources including a flowchart, participant prescreening questionnaire, and  examples of applying the tiering system in practice. These tools will assist researchers in planning and study design that adopts appropriate classification and control of ovarian hormone status of its participants. These guides have been generated from our experiences of implementing a high-quality approach in the applied sports science setting. We discuss the balance between methodological rigor, practical constraints, participant burden, and the generalizability of findings. Ultimately, this paper provides resources to assist researchers in adopting high-quality, suitable approaches to studying female athletes, regardless of available resources thereby facilitating the correction of sex-based research biases in the literature.