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Purpose: This study aimed to investigate the effect of PMS on aerobic, anaerobic, and cognitive performance in female combat athletes. Method: In this semi-experimental study with a repeated measures design, 20 female combat athletes (mean age: 24.5±2.1 years) were assessed during two phases of their menstrual cycle: the PMS phase (7-10 days before menstruation) and the non-PMS phase (days 7-14 of the cycle). Aerobic performance was measured using the Bruce treadmill test, anaerobic performance was assessed by the Wingate test, and cognitive performance was evaluated through simple and choice reaction time tests. Statistical analyses were performed using paired t-tests and Pearson correlation (p<0.05). Results: The findings showed a significant reduction in VO₂ max (6.2%), time to exhaustion, and a significant increase in maximal heart rate and Rate of Perceived Exertion (RPE) during the PMS phase compared to the non-PMS phase (p<0.05). Anaerobic performance also declined, with a reduction in peak power (6.2%) and mean power (7.5%), an increase in fatigue index (16.2%), and lower blood lactate levels (p<0.01). Cognitive performance deteriorated during PMS, demonstrated by increased simple (16.7%) and choice (16.6%) reaction times, more errors, and decreased accuracy (p<0.01). Furthermore, there was a significant positive correlation between PMS symptom severity and VO₂ max reduction (r=0.72), as well as between blood lactate levels and reaction time (r=0.65) (p<0.01). Conclusion: PMS negatively affects aerobic, anaerobic, and cognitive performance in female combat athletes. These findings highlight the importance of considering the menstrual cycle phases in designing training and competition schedules for female athletes to optimize performance and prevent potential declines associated with PMS.

Background: Neuromuscular training (NMT) and supplementation with essential minerals such as calcium (Ca), magnesium (Mg), and zinc (Zn) may enhance muscular reaction time (RT) and electromechanical delay (EMD). However, research on this topic, particularly among taekwondo athletes, is limited.Aim: This study aimed to evaluate the effects of NMT and Cal-Mg-Zn supplementation on RT and EMD in taekwondo athletes.Materials and Methods: Sixty athletes from a single taekwondo club in Tabriz, Iran, were randomly assigned to four groups of fifteen: Control, Ca-Mg-Zn, NMT, and Cal-Mg-Zn + NMT. NMT was conducted in 60 min sessions, four times a week, for six consecutive weeks, prior to main taekwondo training. RT and EMD were measured using electromyography before the intervention (T1), three weeks after (T2), and six weeks after (T3). Data were analyzed using SPSS with a confidence level greater than 0.95, employing repeated measures ANOVA and Bonferroni post hoc tests.Results: No significant differences in RT and EMD were observed among the groups at baseline (P> 0.05). In both post-test assessments, the Cal-Mg-Zn + NMT group exhibited significantly lower RT and EMD compared to the other groups (P< 0.05).Conclusion: The inclusion of NMT with zinc supplementation can effectively improve RT and EMD, thereby enhancing the athletic performance of taekwondo athletes.

This research paper presented a comprehensive analysis of the literature on winter sports tourism, tracing its development over a span of 56 years. It was reviewed with bibliometric techniques with VOSviewer software. The extensive bibliometric analysis revealed emerging trends, notable research contributions, and key participants in the field. Prominent countries in this niche are Australia and Canada, while the Universities of Innsbruck and Waterloo, journals such as Sustainability Journal (Switzerland), and authors such as Falk and Muller, Peters, Scottwere have shown significant focus in this area. Therefore, the study highlights the increasing importance of this niche tourism sector, reflecting a surge of interest in recent years as indicated by the rising number of relevant research papers. The review also underscored how vital bibliographic studies are to comprehending the landscape of winter sports tourism. The findings provided trends, patterns, and a roadmap for prospective researchers, flagging the necessity of keeping pace with the evolving realities of winter sports tourism and establishing a valuable foundation for understanding and examining current trends and future developments in winter sports tourism. That will undoubtedly prove useful for both researchers and decision-makers in the field of winter sports tourism.

Background: Caffeine is widely recognized as a potent ergogenic aid commonly used to enhance exercise performance and recovery. However, individual responses to caffeine can vary significantly, a variability that might be explained by genetic differences.Aim: This study aimed to investigate the influence of the CYP1A2 rs762551 SNP on the effects of caffeine (CAF) consumption on growth hormone (GH) and testosterone (TS) levels response to resistance exercise (RE) in male athletes.Materials and Methods: Thirty resistance-trained men (mean age 21.72±4.06 years, weight 77.31±14.07 kg, height 179.31±5.08 cm) participated in a randomized, double-blind, placebo-controlled, crossover study. They consumed either CAF (6 mg/kg) or placebo (PL; 6 mg/kg maltodextrin) one hour before performing a RE protocol including three sets with 85% of 1RM and two-minute rest. CYP1A2 genotyping categorized participants as AA homozygous ("fast" metabolizers) or AC heterozygous ("slow" metabolizers). GH and TS levels were measured by ELISA methods.Results: Repeated measures ANOVA showed significant differences in GH levels across time (F=10.94, P=0.000), with significant time-group (F=4.3, P=0.019) and time-genotype-group interactions (F=3.83, P=0.024). One-way ANOVA indicated significant differences in GH levels between CAF and PL conditions in AA individuals, but not in AC/CC genotypes. For testosterone, significant effects of time (F=14.88, P=0.000) and time-group interaction (F=3.197, P=0.045) were observed. Post-RE CAF supplementation significantly increased serum GH and TS levels in AA individuals compared to PL. Both CAF and PL groups showed increased serum hormone concentrations post-exercise.Conclusion: In conclusion, the study demonstrated that caffeine consumption significantly increased serum levels of growth hormone and testosterone in individuals with the AA genotype of the CYP1A2 rs762551 SNP. These findings suggest that genetic variations play a role in the hormonal response to caffeine, which may have implications for exercise performance and recovery strategies.

Background: In the past few years, the increasing importance of the impact of exercise on physical and mental health has caused mobility wave around the world. Nevertheless, in Iran, a few people participate in physical activities. Aim: This study aimed to assess the reasons of nonparticipation in physical activity in Iran. Materials and Methods: This research is a descriptive and analytical approach conducted as a field study. The population of this research includes all people in Iran. Results: The results revealed that this factors are effective: three factors in individual characteristics variable (lack of sports skills, fatigue and impatience, fear of injury), four factors in inhibitor variable (lack of access to sports facilities and venues, poor quality of sports facilities and venues, being too busy, low income), four factors in environmental driving variable (lack of proper planning for sports, lack of awareness of the advantage of sport activities, feeling embarrassed after the loss, low number of exclusive sports facilities) and two factors in sports features variable (fear of winning and losing in sports, high intensity and duration of sport activities). Conclusion: Findings indicated that the environmental variable and inhibitor variable were more effective than two other variables, hence authorities and planners should pay more attention to these obstacles and problems with better management and provision of infrastructure facilities. These problems must be solved and strategies must be developed for promotion of sports in the country.