درخت حوزه‌های تخصصی

The present study investigated the effect of eight weeks of training with a gyroscope on identifying the body position in space, the semi-dynamic balance on the ground, and Huber's device score. Two groups of 30 Air Force (IRIAF) pilots with an average age of 27 years, height of 178, and weight of 80 kg were randomly assigned to two training and control groups. The training group was exposed to eight weeks of training with the gyroscope device. The pre-test and post-test of the two groups were compared using videography, star test, and Huber's score using the statistical method of repeated measurement. In the gyro test, there was no significant difference in the detection angle of the body position in the air in any groups before and after the test. However, an increase in rotation speed was observed in the training group. In Huber's test, there was no significant change in the control group before and after. However, in the training group, an improvement in the score was observed, especially in the non-superior limb, as well as a decrease in the difference in the score between the two hands. Stars were not observed in any groups before or after the test. According to the results, it can be concluded that despite the non-significance of the difference in the subjects' ejection angle and position identification in the training group, it occurred simultaneously as the rotation speed increased

The phenomena of fatigue of voluntary muscular effort is intricate and multidimensional in the field of sports sciences. The causes and effects of exercise-induced fatigue have been extensively studied, but the central nervous system's (CNS) involvement in this process is still unclear. In order to understand CNS fatigue after physical activity, the current review will examine changes in neurotransmitter function during exercise. Using primary sources such scientific journals and websites, a consensus and critical evaluation were carried out in order to accomplish this goal. For a number of neurotransmitters, including dopamine and serotonin (5-HT; 5-hydroxytryptamine), hypotheses have been established. The most well-known one is a rise in serotonin levels throughout the brain. Nutritional interventions intended to reduce brain serotonin synthesis during extended exercise enhance endurance performance, and there is strong evidence that increases and decreases in brain serotonin activity during prolonged exercise, respectively, accelerate and delay fatigue. There are several physiologically connected causes of fatigue. It is important to better understand how CNS effects affect fatigue in order to achieve maximum muscle performance in both daily life and athletics.

Background: Shoulder impingement syndrome is a common complication that causes pain and disability, functional limitations and reduced quality of life. This syndrome is usually seen in people who are involved in activities and sports involving rotating movements above the head, including bodybuilders. Meanwhile, corrective exercises have been considered as an intervention in the rehabilitation of the condition. Exercises based on National Academy of Sports Medicine (NASM) principles are known as one of the new methods in the rehabilitation and prevention of sports injuries.Aim: The purpose of this study was to investigate the effect and permanence of corrective exercises on pain intensity, functional disability and kinematic parameters of bodybuilders with shoulder impingement syndrome.Materials and Methods: In this semi-experimental research with a pre-test-post-test design, 20 male bodybuilders with shoulder impingement syndrome were randomly assigned in two groups; corrective exercises as the experimental group (n=10) and control group (n=10). Visual Analog Scale (VAS) questionnaire was used for pain intensity. Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire was used for functional disability. Kinovea software was used to kinematic parameters. The evaluations carried out during three stages: the pre-test, the first post-test (after 8 weeks) and the second post-test (after 12 weeks). Data were analyzed using descriptive statistics, repeated measures analysis of variance (ANOVA) at a significance level of 0.05 using SPSS version 20 software.Results: The findings showed that after 8 weeks of corrective exercises, there were significant changes in pain intensity and functional disability in the experimental group (P<0.05). Also, significant changes in shoulder biomechanical parameters during flexion, abduction, external rotation and internal rotation movements were observed between the two groups (P<0.05). Permanence of the exercises in the studied variables after 12 weeks showed a significant difference between the two groups (P<0.05).Conclusion: According to the obtained results, it can be stated that a course of NASM exercises reduced shoulder pain, improved functional disability and improved kinematic parameters in male bodybuilders with shoulder impingement syndrome.

The purpose of this study is to compare the performance indicators between different football positions using the Global Positioning System (GPS) in Iranian Premier League football players. This is quasi-experimental study. To conduct this research, 18 football players who are members of a club in the Iranian Premier League were selected as the available sample, and the players were divided into 6 groups based on the game post. Then the data related to the players' performance (total distance, distance traveled with maximum speed, duration of maximum speed, maximum speed, sprints, number of accelerations, and number of decelerations) in 6 consecutive matches Collected using Global Positioning System (GPS). Also, one-way ANOVA analysis and SPSS software were used for data analysis at a significant level (α = 0.05). Based on the findings of the present study, between different football positions for the variables of total distance (P≤0.00), distance traveled at maximum speed (P≤0.00), duration of maximum speed (P≤0.00), maximum speed (P≤0.00), sprints (P≤0.00), number of accelerations (P≤0.00) and number of decelerations (P≤0.00) there are significant differences. There are many fundamental differences between the performance indicators of different football positions with each other it is necessary to recognize these differences and it is necessary to consider special exercises according to the physiological needs of each post.