درخت حوزه‌های تخصصی

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.

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.

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.