Effect of different speeds and ground environment of squat exercises on lower limb muscle activation and balance ability.

Abstract

Squat is the most important exercise for the strengthening of the lower limb muscles. The muscle contraction speed and type affect the muscle activation, strength, and power. This study aimed to investigate the influence of two different speeds of squat exercise on the activation and balance of the lower limb muscles. Thirty-eight healthy adults randomly performed squat exercises at different speeds and in different ground environments, 3times per week for 4weeks. The participants' lower limb muscle activation and balance ability were evaluated before and after the training. There was a significant difference in muscle activation between the squats in terms of speed (fast, moderate, and slow squat) (p< 0.05). After the training periods, there was a significant difference in the rectus femoris (RF) and biceps femoris (BF) of the groups that performed the fast squat (p< 0.05). There was significant difference between the pre- and post-static balance test in the group that performed fast squats on an unstable surface (p< 0.05). After the training periods, the stability index with eyes open values, which is static balance, showed a significant difference among the groups after 4weeks (p< 0.05). The groups that performed fast squat showed a significant difference between the pre- and post-dynamic Y balance test (p< 0.05). For optimal performance and effect of selected squat exercises, the speed and ground environment should be taken into consideration.