Evaluation of muscle activity level in the lower extremities during various steps used in aerobic dance exercise

Abstract

To create a safe and effective aerobic dance exercise (ADE) program, the intensity, and difficulty level of each step, and muscle activation during the program must be considered. This study evaluated the muscle activity levels of the lower extremities when major ADE movements were repeated at a fixed speed. The subjects were seven females 21-22 years old who were familiar with the ADE movements. Eleven low impact steps and nine high impact steps representative of the ADE movements were selected, and while the movements were performed, the surface electromyograms (EMG) of six muscles in the lower extremities were measured using a telemeter electromyograph. The EMG data for 10 cycles of each step were full wave rectified and integrated. Then, the average value per unit time was calculated, and normalized (%EMGmax) by the EMG integral value during isometric maximum voluntary contraction (EMGmax). The EMGmax was measured for each of the six muscles to evaluate the muscle activity level, and determine which muscles were activated at higher or lower levels in response to the specific steps. The highest levels of total muscle activity detected in the six muscles were for: double hop, jumping jack, and pendulum. The results of this study may help create ADE programs that consider the differences in muscle activation in the lower extremities.