The Role of Muscle Fiber in Reactive Balance of Athletes and Non-Athletes

Background: The most important part of the ability of an athlete is balancing, a function that involves different muscular nervous processes. When creating unexpected disturbances, muscle strength is one of the most important factors in maintaining a person's balance. Objective: The purpose of this study was to determine the relationship between type II muscle fibers and reactive balance in athlete and non-athlete males. Methods: A total of ۱۷۱ volunteers were selected from the statistical population which included all male students of Kharazmi University. After eliminating non-qualified individuals, four groups of ۳۰ were equally purposeful in terms of the level of performance and the type II of muscle fiber (ie, athlete / high percentage, athlete / low percentage, non-athlete / high percentage and non-athlete / low percentage) were analyzed as statistical samples. The type of muscle fiber was evaluated indirectly by using the Torstenson test on the Isokinetic Biodex dynamometer. Also, the balance response of the subjects was assessed with a computerized Dynamic Posturography (CDP) using the motor control test. Pearson correlation was used to determine the correlation between the type of muscle fiber and balance recovery time delay. A multivariate analysis of variance analysis with Bonferroni's post hoc test was used to compare the mean delay time between athletes and non-athletes with high and low percentages of type II muscle fiber. Results: The results showed a significant correlation between the high percentage of type II muscle intramuscular and reactive equilibrium in athletes and non-athletes with the high percentage of type II muscle in the anterior axis (P = ۰.۰۰۵, P = ۰.۰۰۲) and posterior (P = ۰.۰۰۲ and P = ۰.۰۳۷) respectively. However, there was no significant correlation between the low percentage of type II muscle and reactive balance in both groups with a low percentage of type II muscle fiber (p≥۰.۰۵). In addition, there was a difference between athletes and non-athletes with high and low percentage of type II muscle fiber in response to anterior and posterior axial disturbances (P = ۰.۰۰۰). Conclusion: The results of this study showed that there is a relatively high correlation between the type of muscle in knee extensors and reactive balance in disturbances of both posterior and anterior axis. In particular, a better understanding of the relationship between the type of muscle and reactive balance is the basis for identifying and identifying individual risks, as well as identifying strategies to reduce the rate of decline of muscle with type II fiber.

Keywords:

Athlete , Muscle Fiber , Reactive Balance , Non-Athlete