درخت حوزه‌های تخصصی

Background: Plyometric training is defined as a quick, powerful movement involving a system of reactive exercises and an eccentric contraction, followed immediately by an explosive concentric contraction. Aim : This study aimed to determine the effect of plyometric and aerobic training on peak power and performance in female elite rowers. Materials and Methods: Sixteen female elite rowers with a minimum of 1 year’s competitive rowing experience were recruited to perform six weeks of plyometric or cycling endurance training for 30 min before practice on the water three days per week. Rowing performance was assessed through a 500-m rowing time trial (TT), while peak rowing power (PR) was evaluated by over three maximal trials of 15 s on the rowing ergometer. The recorded value for peak power was the highest wattage observed during the 15-s period. All statistics were performed using commercially available software (SPSS v. 23, Armonk, NY). Pre-planned t-test comparisons were used to determine significance at baseline in changes within both groups. Results: The results showed 500-m TT performance significantly improved for the plyometric group ( P < 0.05) but not for the endurance group ( P > 0.05). Moreover, PR was considerably higher in the plyometric group in post-test than endurance training. Conclusion: These results suggest that plyometric can improve rowing performance in female elite rowers, and rowing coaches should continue using this form of training. Coaches can perform plyometrics in conjunction with other strength training methods or as a warm-up before beginning rowing-specific training.

Purpose: Osteoporosis is a decrease in bone density among older adults that can cause painful fractures and disability. One of the most important effective non-pharmacological interventions is having appropriate and continuous physical activity.  The aim of this study was to investigate the relationship between serum calcium and alkaline phosphatase with femur bone mineral density in active and inactive men. Method: This study was semi-experimental. 35 active and 35 inactive elderly men aged 65 to 80 years with medical records were selected. Anthropometric characteristics, serum calcium and alkaline phosphatase of subjects were used as effective indicators of osteoporosis. Pearson's correlation coefficient was used to find the relationship between femur mineral density and serum calcium and alkaline phosphatase, data analysis was done using SPSS version 26 Software. Results: The results of this research showed that in both groups of active and inactive men, there was a significant relationship between serum calcium and alkaline phosphatase and femur mineral density (P≤0.05). No significant relationship was found between the height index and mineral density of the femur (P≥0.05). Conclusions: In general, the results show that there is a significant relationship between bone density and weight, age, calcium, phosphorus, and serum alkaline phosphatase of all subjects, and the effect of exercise on other bone density indicators can be investigated.

The political challenges invite sport to play a peaceful role in international relations. Among all these challenges, national security is a critical part of different states. This study tried to investigate the conceptual framework of sport and national security. The present study was qualitative based on descriptive and applied methods. At first, the literature reviews were studied, and then the semi-open interviews were done with 12 experts in sport sciences and policymakers. After 3 rounds of the Delphi technique, 15 concepts were extracted in 5 main dimensions: economic, military, political, social, and health. Finally, the sport seems to play a vital role in supporting various aspects of security. Iran, as a country under the most severe sanctions on its political economy, can use the phenomenon of sport as a lever to mitigate the effects of international sanctions on its economy, politics, and security in general.

Background & Aim: This study aimed to investigate the effect of cardio kickboxing workouts on cardiorespiratory endurance, body composition, quality of life, and sleep quality of young male students living in dormitories. Methods: The research method was a quasi-experimental pretest-posttest design with a control group. To carry out this research, 20 male students in the Allameh Tabatabaei University dormitory were randomly selected and divided into two experimental and control groups, each group consisting of 10 people. In order to determine cardiorespiratory endurance, body composition, quality of life, and sleep quality, Queen''''''''s College Step Test (QCT), body fat percent using calipers, 36-Item Short-Form Health Survey questionnaire (SF-36), and Pittsburgh Sleep Quality Index (PSQI) were employed, respectively. Results: Based on the analysis of covariance of the data related to pretest and posttest of the two experimental and control groups, the data of four variables of fat percentage, cardiorespiratory endurance, quality of life, and sleep quality in the posttest were significantly different between the two groups that this statistical test was conducted at a significance level of P = 0.05. Conclusion: It appears that cardio kickboxing workouts have a positive impact on the health of male students in dormitories.