The Effects of Core Stability Exercise Using an Ultrasound Imaging System on Muscle Activation of Shoulder Region

Core stability exercise is known to have an effect on muscle activation in the shoulder region. Twenty-three healthy adult men and women, aged 19 to 27 years, volunteered to participate in this study. The purpose of this study was to examine the effect on shoulder region muscle activation during the presence or absence of the core stability. Muscle activation was measured by surface EMG and ultrasound imaging during the exercise, and was simultaneously recorded from upper trapezius, low trapezius, and serratus anterior muscles in surface EMG. EMG values were normalized by maximum muscle contractions (%maximum voluntary isometric contraction; [%MVIC]). A paired t-test was used to compare the differences in the muscle activation according to the presence or absence of the core stability. In the results of this study, when subjected to core stability exercise, EMG activation of the upper trapezius muscle decreased by 19%, and the serratus anterior muscle increased by 11%(p .05). These findings suggest that core stability shoulder exercise could be more effective in the shoulder region in patients with chronic shoulder pain.