Exercise Physiology
Gholamreza Sharifi; alireza babaei mazreno; Seyed Amir Ahmad Mozafari; Mohammad Kamali
Abstract
Purpose: The aim of this research is to compare the effects of three training methods — plyometric, weighted, and barbell (Turkish) training — on the anaerobic capacity of high school male volleyball players. A total of 48 subjects, aged 23 ± 5 years, were selected purposefully and ...
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Purpose: The aim of this research is to compare the effects of three training methods — plyometric, weighted, and barbell (Turkish) training — on the anaerobic capacity of high school male volleyball players. A total of 48 subjects, aged 23 ± 5 years, were selected purposefully and randomly divided into four groups of 12 participants each. Method: The height and weight of the participants were recorded, and their anaerobic capacity was measured using the Lewis formula based on the vertical jump test during the pre-test. The three experimental groups performed weight training, plyometric exercises, and plyometric exercises combined with weights, respectively. The fourth group followed a standard volleyball training regimen. The training period lasted eight weeks, with three training sessions per week. After the eight weeks, a post-test was conducted to measure the effects of the different training methods on the participants' anaerobic capacity. Results: The results of this study showed: Eight weeks of weight training significantly improved the anaerobic capacity of the volleyball players eight weeks of plyometric training significantly improved the anaerobic capacity of the volleyball players. Eight weeks of barbell (Turkish) training significantly improved the anaerobic capacity of the volleyball players.There was no significant difference between the effects of the three training methods on anaerobic capacity. Conclusion: Based on the results of this research, it can be concluded that weight training, plyometric training, and barbell training are all effective in increasing the anaerobic capacity of volleyball players. Given the available time, number of athletes, and resources, any of these training methods can be selected to improve the anaerobic power of athletes. Coaches may choose the most appropriate method depending on the specific needs of their athletes and the resources available.
Exercise Physiology
Asghar Abassi; sirwan Mohammad Amini Khayat
Abstract
We were very interested in the recent research focused on evaluating cardiovascular performance in young populations. The maximal oxygen pulse (O₂Pmax), calculated as the ratio of peak oxygen uptake (VO₂peak) to peak heart rate (HRpeak), has become an important, non-invasive marker for assessing ...
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We were very interested in the recent research focused on evaluating cardiovascular performance in young populations. The maximal oxygen pulse (O₂Pmax), calculated as the ratio of peak oxygen uptake (VO₂peak) to peak heart rate (HRpeak), has become an important, non-invasive marker for assessing cardiopulmonary function. Nevertheless, direct measurement through cardiopulmonary exercise testing (CPET) is often impractical for large-scale studies. highlighting the need for reliable estimation methods. Although several such protocols are available for adults. their accuracy in adolescents—who experience significant physiological changes—has not been thoroughly validated. Our study sought to address this by comparing O₂Pmax estimates derived from one laboratory-based and three field-based exercise tests against a standard reference in adolescent males. We conducted a cross-sectional study involving 60 healthy adolescent boys (mean age 16.05 ± 0.81 years). Participants underwent four exercise tests in a randomized order: a Graded Exercise Test (GXT) on a treadmill, two cycle ergometer tests (PWC195 and PWC212)
Exercise Physiology
Noushin Azadpour; behzad hajizadeamini; sirwan mohammad amini; ali arman
Abstract
Background: The "athlete's heart" syndrome encompasses structural and functional cardiac adaptations to chronic exercise. These sports impose unique hemodynamic loads, potentially leading to distinct remodeling patterns.Objective: This study aimed to compare central cardiovascular adaptations, both structural ...
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Background: The "athlete's heart" syndrome encompasses structural and functional cardiac adaptations to chronic exercise. These sports impose unique hemodynamic loads, potentially leading to distinct remodeling patterns.Objective: This study aimed to compare central cardiovascular adaptations, both structural and functional, in elite male athletes from basketball, volleyball, and handball to identify sport-specific differences.Methods: Thirty male athletes (aged 18-25; n=10 per sport group) participated in this cross-sectional study. All participants underwent comprehensive transthoracic echocardiography at rest and immediately following a maximal graded exercise test (GXT) on a treadmill. Key measured parameters included left ventricular (LV) dimensions, wall thickness, mass, ejection fraction (EF), stroke volume, and cardiac output. Data were analyzed using One-Way ANOVA or the Kruskal-Wallis test, with post-hoc analyses where appropriate.Results: While most parameters indicated a common adaptive athlete’s heart profile across all sports, significant sport-specific differences were found. Handball players exhibited a significantly higher heart rate post-GXT (180.11±9.45bpm) compared to both basketball and volleyball players (p<0.01). Furthermore, ejection fraction was significantly different between all groups at rest (p<0.05), with handball players also demonstrating a superior EF post-GXT compared to the other groups (p<0.05). A significant difference in left ventricular end-systolic dimension was also observed at rest between all three sports (p<0.001).Conclusion: The significant differences in post-exercise heart rate and ejection fraction, particularly in handball players, suggest that the pronounced upper-body and isometric components of handball impose a unique hemodynamic stress, leading to distinct functional adaptations. This underscores the importance of sport-specific interpretation of cardiac parameters in athletes.
Exercise Physiology
Narges Fasihi; Reza Gharakhanlou
Abstract
Objective: Plasma follistatin and leptin proteins are important indicators in energy and metabolism regulation that also affect body weight. The aim of this study was to investigate the effect of resistance training with and without blood flow restriction on serum follistatin and leptin levels in inactive ...
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Objective: Plasma follistatin and leptin proteins are important indicators in energy and metabolism regulation that also affect body weight. The aim of this study was to investigate the effect of resistance training with and without blood flow restriction on serum follistatin and leptin levels in inactive obese girls.Materials and Methods: Thirty inactive obese girls with an age range of 20 to 28 years participated in this study. The subjects were randomly divided into 3 groups: resistance training with blood flow restriction and resistance training without blood flow restriction, and a control group (10 subjects in each group). Data analysis was performed using paired t-tests and one-way ANOVA at a significance level of less than 5%.Results: After 12 weeks of participation in sports activity, follistatin levels in both resistance training groups with and without blood flow restriction increased significantly after training (p<0.05). On the other hand, leptin levels decreased significantly in these groups after training interventions (p<0.05). Regarding the main effect of groups, the results showed that there was a significant difference between the types of resistance training and the control group in follistatin (P=0.036) and leptin (P=0.015) levels.Conclusion: The findings indicate that resistance training can lead to an increase in plasma follistatin levels and a decrease in leptin in inactive obese girls. It is recommended that obese individuals use such resistance training with blood flow restriction as a non-invasive, low-cost, and side-effect-free method to promote health and lose weight
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