General users only can access the published articles
Showing 5 results for Subject:
Dr Rasoul Eslami,
Volume 0, Issue 0 (11-2019)
Abstract
Introduction: Blood flow restriction (BFR) has been shown to induce local hypoxia. Therefore, the purpose of this study was to investigate the effect of BFR-induced hypoxia on the angiogenic response to high-intensity interval exercise (HIIE). Methods: Thirty active young men (age =25.6±3.4) were randomly assigned to three groups (n=10 each): control, high-intensity interval exercise (HIIE), and high-intensity interval exercise with blood flow restriction (HIIE+BFR). The HIIE protocol consisted of 5 sets of 5×30-second high-intensity running intervals with 30-second rest periods. BFR was applied at 60% of each individual's optimal occlusion pressure in the lower limbs. Serum levels of VEGF, HIF-1α, MMP-9, and MMP-2 were measured as angiogenic markers. Statistical analysis was performed using ANCOVA with LSD post-hoc test, with the significance level set at α=0.05. Results: The data revealed that compared to both the control and HIIE groups, the HIIE+BFR group showed significantly greater increases in serum VEGF and HIF-1α levels (P=0.002 and P=0.019, respectively). However, no significant differences were observed among groups for MMP-9 and MMP-2 levels (P=0.318 and P=0.101, respectively). Conclusion: This study demonstrated that combining HIIE with BFR can enhance the angiogenic response through increased VEGF and HIF-1α levels, but does not significantly affect MMP-2 and MMP-9. These findings support the notion that BFR-induced local hypoxia may serve as a complementary stimulus for improving vascular adaptations.
Mr Mohamadreza Hatefi, Dr Ramin Balochi, Dr Farideh Babakhani,
Volume 19, Issue 21 (9-2021)
Abstract
The purpose of this study was to investigate the effect of different hip joint postures on electromyographic activity of selected lower limb muscles during squat's movement. Electromyographic activity of selected lower limb muscles of 15 healthy male students was recorded while performing a squat with neutral, 15°, 30°, 45° external and internal rotation of the hip. Friedman's nonparametric test was used to compare muscle activation at different angles of the hip rotation and the Wilcoxon test was used to determine within-group differences. The results of this study showed no significant difference in the activity of Vastus medialis (p = 0.052), Vastus lateralis (p = 0.102) and tensor fasciae lata (p = 0.193) in squat between different hip joint angles, but Significant differences were observed in gluteus medius muscle activation (p = 0.001) and biceps femoris (p = 0.015) in squat between different hip joint angles. Also, the results of this study showed that gluteus medius to tensor fascia lata activation ratio was significant in squat between different hip joint angles. squat with the external hip angles can be considered as an effective method to increase gluteus medius activation and gluteus medius to the tensor fasciae latae activation ratio. On the other hand, 45 ° external and 30 ° internal hip angles can be considered as an effective method to increase the biceps femoris activation.
Dr Rasul Eslami, Navab Abnama,
Volume 20, Issue 24 (3-2023)
Abstract
The aim of the present study was to investigate The effect of HMB-FA supplementation on the muscle damage markers after soccer matches. 24 male soccer players (age: 23±3 years, BMI: 22.8±2 kg/m2) were voluntarily selected as the statistical sample of this study and were divided into two Suppplement and Placebo groups (n=12). In this study, subjects participated in a weekly soccer microcycle with two matches. Subjects in the supplement-training group consumed three grams of HMB-FA daily during a weekly soccer cycle. Blood samples were taken in seven times (before supplementation, before the first match, immediately after the first match, 24 hours after the first match, before the second match, immediately after the second match, 24 hours after the second match). Plasma concentrations of creatine kinase (CK) and lactate dehydrogenase (LDH) were measured by ELISA kits. Data analysis was performed using Friedman, Wilcoxon, Kruskal-Wallis and U Mann-Whitney tests with a significance level of p ≥ 0.05. After supplementation, a significant decrease in plasma levels of lactate dehydrogenase (before and after the first match) and creatine kinase (in the times immediately after the first match and before the second match) was observed (for all, p <0.05). Intaking HMB-FA supplement reduced the markers of muscle damage, which is essential for recovery from injuries caused by training and competition during a two race cycle. In addition, inaking HMB-FA supplement may have other effects, including reducing neuromuscular fatigue, reducing the inflammatory response, and rapid skeletal muscle regeneration, which requires further study.
Dr Ramin Balochi, Dr Farideh Babakhani, Dr Mohamadreza Hatefi, Mr Hossien Hassanpor,
Volume 21, Issue 25 (9-2023)
Abstract
The purpose of this study was to investigate the effect of eight weeks of core stability exercises on upper limb performance based on Y balance test, strength and range of motion of shoulder rotation in badminton athletes. 30 male badminton players were randomly assigned to two control (n=15) and experimental (n=15) groups. The experimental group performed the core stability training program for eight weeks, three sessions a week for 40 minutes, while the control group did not receive any intervention. Measurement of upper limb function was done by Y balance test, and also shoulder strength and internal and external rotation range of motion were measured by handheld dynamometer and goniometer respectively, before and after the intervention. The analysis of the data obtained from the research based on the ANCOVA statistical test showed that there is a significant difference in the average of the Y upper limb balance test between the two control and experimental groups in both dominant and non-dominant hands. which indicates the positive effect of core stability exercises on people's performance in performing the Y balance test (p<0.05); however, no statistical difference was observed in muscle strength and range of motion of external and internal rotation of the shoulder after the intervention. (p < 0.05). It seems that the provision of core stability training programs can be considered with the approach of increasing the performance of the upper limbs and, of course, preventing injuries in badminton players.
Amir Fatollahi, Amirali Jafarnezhadgero, Hamidreza Maghami,
Volume 22, Issue 27 (8-2024)
Abstract
Biomechanics is the knowledge that shows what forces enter the motion system of the human body and how it causes human movement. Therefore, the aim of this Meta-Analysis study was to review the studies conducted in the field of the effects of training on sand surface on biomechanics and physical fitness factors of human body during translational motions. The current study was a library and systematic review, the search for articles in Persian and Latin was from the beginning of the year 2000 to the end of 2023, which was done in the specialized databases of PubMed, WOS, Scopus, ISC and Google Scholar search engine. 568 related articles were selected based on inclusion and exclusion criteria. Standardized mean differences (SMDs) were calculated using random-effects models. The findings of eight articles indicated the improvement of mucle activity during training on sand. Examining the findings of one article indicated positive effects of kinematic variabls during training on sand. A number of two articles also reported that the reduction of the ground reaction forces and impact shock. In addition, five articles reported the improvement of sports performance in athletes, the increase of physical fitness factors. In general, training on sand surface can have significant positive effects on people's daily and sport life. Further study is warranted.
