Shoulder Muscle Activation Levels During the Push-Up Plus Exercise on Stable and Unstable Surfaces.
Indexed on: 15 Jun '16Published on: 15 Jun '16Published in: Journal of sport rehabilitation
Abstract
The aim of this study was to evaluate the acute effect of the use of stable and unstable surfaces on EMG activity and coactivation of the scapular and upper limb muscles during performing push-up plus (with full protraction of the scapula). Muscle activation of anterior deltoid (AD), posterior deltoid (PD), pectoralis major (PM), biceps brachii (BB), triceps brachii (TB), upper trapezius (UT), middle trapezius (MT), lower trapezius (LT) and serratus anterior (SA) levels and coactivation index were determined by surface electromyography in 20 young men during push-up plus performed on a stable and unstable condition (two unstable devices applied to hands and feet). The paired t-test and Cohen's d were used for statistical analysis. The results showed that during the execution of the push-up plus on the unstable surface an increased EMG activity of the scapular stabilizing muscles (SA, MT and LT) was observed, while AD and PD muscles showed a decrease. During exercise execution on the unstable surface there was a higher index of coactivation of the scapular muscles (SA-MT and UT-LT pairs). No significant differences were observed in TB-BB and AD-PD pairs. These results suggest that the push-up plus exercise associated with unstable surfaces produced greater EMG activity levels and coactivation index of the scapular stabilizing muscle. On the other hand, the use of unstable surface does not promote the same effect for the shoulder muscles.
