درخت حوزه‌های تخصصی

Purpose: Winter endurance training combines high aerobic load with repeated cold exposure, which can alter immune-related cellular signaling and increase vulnerability to upper respiratory tract infections (URTI), thereby threatening training continuity and performance. This structured abstract aimed to summarize a signaling-based rationale for immune-informed winter periodization in endurance runners. Method: A narrative, mechanistic synthesis was developed from exercise immunology and cold-stress evidence, focusing on how cold exposure and endurance exercise converge on sympathetic nervous system and hypothalamic–pituitary–adrenal (HPA) axis activation, downstream endocrine responses (catecholamines, cortisol), immune cell trafficking, airway barrier function, mucosal immunity (salivary IgA), and cytokine signaling (with emphasis on IL-6). Practical implications were translated into microcycle/mesocycle design principles and a tiered monitoring framework. Results: Cold exposure triggers thermoregulatory vasoconstriction and central blood redistribution and is accompanied by neuroendocrine shifts that can modify leukocyte behavior, adhesion signaling, and lymphocyte proliferation. Evidence indicates that respiratory barrier defenses may be impaired in cold conditions, while mucosal immunity (e.g., IgA-related protection) can be reduced in heavily trained athletes during winter, coinciding with increased URTI reports. IL-6 responses to exercise in the cold were context-dependent: some protocols show minimal temperature effects at moderate intensity, whereas others report higher IL-6 at colder temperatures, supporting a multi-marker and longitudinal interpretation rather than reliance on single measurements. Conclusion: Integrating cellular signaling knowledge enables temperature-aware planning of intensity, structured warm-up/rewarming routines, monotony control, and symptom-gated adjustments to reduce “vulnerability windows” without sacrificing adaptation. Immune-informed winter periodization, supported by feasible monitoring (load, sleep, symptoms, and optional IgA/cytokines), may preserve training availability and mitigate winter performance decrement in endurance runners.

Purpose: Extreme sport tourism has become a rapidly expanding segment of the global tourism industry, involving high-risk activities such as rafting, climbing, sky running, and canyoning. The objective of this review was to synthesize current scientific evidence on the physiological and organizational determinants of safety in extreme sport tourism and to present an integrated framework applicable to diverse adventure sport contexts. Method: A narrative review methodology was adopted. Peer-reviewed studies published between 2000 and 2025 were identified through PubMed, Scopus, Web of Science, ScienceDirect, and Google Scholar. Included studies addressed physiological stress responses, environmental exposure, guide competence, safety management systems, and emergency preparedness in extreme or adventure sport settings. Findings were thematically synthesized across physiological and organizational domains. Results: The review identified key physiological determinants of safety, including cardiovascular strain, hypoxic and respiratory stress, thermoregulatory imbalance, dehydration, neuromuscular fatigue, and neuroendocrine stress responses, all of which influence performance, cognition, and decision-making under extreme conditions. Organizational determinants included structured risk assessment, guide training and certification, equipment standards, communication systems, emergency response planning, and organizational safety culture. Evidence indicated that inadequate organizational control amplifies physiological risk and contributes to accident occurrence. Conclusion: Safety in extreme sport tourism requires an integrated, multidisciplinary approach aligning human physiological limits with organizational management to improve participant safety and support sustainable destination development.

Purpose: Aging is accompanied by progressive mitochondrial dysfunction and increased oxidative stress, particularly within the hippocampus, a brain region highly vulnerable to metabolic impairment and redox imbalance. Curcumin, a polyphenolic compound with potent antioxidant and anti-inflammatory properties, and high-intensity interval training (HIIT), a time-efficient exercise modality known to stimulate mitochondrial biogenesis, may offer complementary neuroprotective benefits. This study examined the synergistic effects of curcumin supplementation and HIIT on mitochondrial antioxidant enzymes in the hippocampus of aged rats. Method: Thirty-two male Wistar rats (22–24 months) were randomly assigned to four groups: Control, Curcumin (100 mg/kg/day), HIIT, and Curcumin + HIIT. The 8-week HIIT protocol consisted of treadmill-based intervals performed five days per week, while hippocampal mitochondrial fractions were analyzed for superoxide dismutase 2 (SOD2), catalase (CAT), and glutathione peroxidase (GPx). Oxidative stress markers, including reactive oxygen species (ROS), malondialdehyde (MDA), and reduced glutathione (GSH), were also quantified. Results: Both curcumin and HIIT independently increased SOD2, CAT, and GPx activities (p < 0.01), but the combined intervention produced significantly greater enhancements across all enzyme systems (p < 0.001). ROS and MDA levels were markedly reduced in the Curcumin + HIIT group compared with all other groups (p < 0.001), while GSH content increased by more than 100% relative to controls. Effect sizes were large for all mitochondrial and oxidative stress outcomes, indicating robust physiological adaptation. Conclusion: These findings demonstrate that curcumin supplementation synergistically enhances the mitochondrial antioxidant and redox benefits of HIIT in the aging hippocampus. Integrating targeted nutraceuticals with structured high-intensity exercise may represent a promising strategy for mitigating age-related oxidative dysfunction and supporting long-term brain health.

Purpose: The acute ventilatory response to exercise in adolescents is a critical indicator of cardiorespiratory fitness, yet the predictive power of basic anthropometric measures for this response, particularly in field-based settings, is not fully established. This study aimed to investigate the relationship between anthropometric variables (height, weight, BMI) and acute ventilatory responses both at rest and immediately following a maximal one-mile (1600m) field run in healthy adolescent boys. Method: In a pre-test/post-test experimental design, 80 healthy adolescent boys (mean age: 14.65 ± 1.22 years, height: 168.20 ± 9.72, body mass index: 19.54 ± 2.80) were selected via cluster sampling. Anthropometric data (height, weight, BMI) and estimated VO₂max were recorded. Pulmonary function variables (FVC, FEV₁, VC, TV, MVV) were measured via spirometry at rest and immediately after a maximal one-mile run. Stepwise multiple regression analysis was used to predict ventilatory responses from anthropometric and physiological variables. Results: Height, weight, and BMI were all significant predictors of pulmonary function (FVC, FEV₁, VC) in both pre- and post-test conditions (p < 0.05). Height emerged as the strongest single predictor. A slight but consistent decrease in mean FVC, FEV₁, and VC values was observed post-exercise. VO₂max was a weaker predictor compared to anthropometric measures. Conclusion: Basic anthropometric characteristics, most notably height, are strong and consistent predictors of pulmonary function in adolescent boys, both at rest and following acute strenuous exercise. These findings highlight the importance of using individual morphometric characteristics for accurately assessing and interpreting exercise-induced ventilatory responses in youth populations. Field-based testing provides a valid practical method for such evaluations.

This study deals with the effect of structural empowerment on professional commitment of male referees with the mediating role of job characteristics in Iranian football premier League. Datacollected using a self-report survey. In addition to demographic items, the survey comprised 46 items measuring structural empowerment, professional commitment and, job characteristics. Experts in sports management and football refereeing confirmed the face and content validity of the questionnaire. 130 valid questionnaires completed by referees in the Persian Gulf Pro League in Iran. Structural equation modeling, confirmatory factor analysis and, path analysis were conducted for data analysis by using PLS Smart software. The effects of structural empowerment on professional commitment (T-Value= 2.27 and ß= -0. 18) and job characteristics on professional commitment (T-Value = 8.93 and ß = 0.63) were both positive and significant. The effect of structural empowerment on job characteristics (T-Value = 4.94 and ß = 0.43) was positive and significant. Referee’s Job characteristics had a significant mediating role in the relationship between structural empowerment and their professional commitment (T-Value= 4.15, ß= 0.27). The findings can provide critical insights for sport managers be more efficient in the field of football refereeing.