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

Abstract

BACKGROUND:

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.

OBJECTIVE:

This study aimed to investigate the influence of two different speeds of squat exercise on the activation and balance of the lower limb muscles.

METHODS:

Thirty-eight healthy adults randomly performed squat exercises at different speeds and in different ground environments, 3 times per week for 4 weeks. The participants’ lower limb muscle activation and balance ability were evaluated before and after the training.

RESULTS:

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 4 weeks ( $p<$ 0.05). The groups that performed fast squat showed a significant difference between the pre- and post-dynamic Y balance test ( $p<$ 0.05).

CONCLUSIONS:

For optimal performance and effect of selected squat exercises, the speed and ground environment should be taken into consideration.