Relative balance of serratus anterior and upper trapezius muscle activity during push-up exercises.

Background: Serratus anterior strengthening is used in prevention and treatment programs for poor scapular control. In certain clinical cases, exercises substantially activating the serratus with minimal upper trapezius activation are preferred.

Hypothesis: The standard push-up plus would show both the highest serratus anterior activation and lowest upper trapezius/ serratus ratios for both groups and all phases.

Study Design: Controlled laboratory study.

Methods: Thirty subjects, grouped as healthy or with mild shoulder dysfunction, were evaluated performing standard push-up plus exercises and modifications on elbows, knees, and against a wall. Surface electromyography of the serratus anterior and upper trapezius was compared between exercises.

Results: Both groups responded similarly across exercises. The standard push-up plus demonstrated the highest activation of the serratus (to 123%) and lowest trapezius/serratus ratios (<0.2) during plus phases. The wall push-up plus and phases of other exercises demonstrated higher upper trapezius/serratus ratios (to 2.0).

Conclusions: In clinical cases where excess upper trapezius activation or imbalance of serratus and trapezius activation occurs, the push-up plus is an optimal exercise. Other cases may benefit from a progression of modified push-up exercises.

Clinical Relevance: Clinical selection of exercises for improving scapular control should consider both maximum serratus activation and upper trapezius/serratus anterior ratios.