Effects of Unstable Support Surface and Weight Load on Muscle Activity and Balance During Squat Exercise

Abstract

Purpose: The purpose of this study is to find and compare the differences between muscle activity change and balance during unstable support and weight load during the squat exercise. Methods: The subjects were 36 normal adults (18 male and 18 female). It was randomly divided into a stable support group (control group), an unstable support group (experimental group 1), and an unstable support surface weighted group (experimental group 2), and the squat exercise was performed for 4 weeks. Togu jumper (TOGU, Germany) was applied as the unstable support surface, and 4 kg of Kettlebell (Schmidt, China) was applied for the weight load. The squat exercise was conducted three times a week and consisted of 10 minutes of warm-up, 20 minutes of the main exercise, and 10 minutes of down exercise. This exercise was repeated three sets of 15 squats. Results: The result is as follows. First, changes in muscle activity according to the experimental period increased in both the stable and unstable support groups and the unstable support and the largest increase in the weight load group (p<.05). Second, change in the balance ability according to the experiment period was most improved in the unstable support according to the experiment period in the change of Endpoint excursion (EPE) and the Directional control (DCL) than the other two groups (p<.05). Conclusion: Squat exercise is effective as an exercise to improve the strength and balance of leg muscles. As in previous studies, it was found that exercise is more effective on the unstable support than on the stable support and that it is most effective to give weight load on the unstable support.