Comparison of electromyographic activity of the lower trapezius and serratus anterior muscle in different arm-lifting scapular posterior tilt exercises.

OBJECTIVE: To determine the most effective exercise to specifically activate the scapular posterior tilting muscles by comparing muscle activity generated by different exercises (wall facing arm lift, prone arm lift, backward rocking arm lift, backward rocking diagonal arm lift).
DESIGN: Repeated-measure within-subject intervention. PARTICIPANTS: The subjects were 20 healthy young men and women. MAIN OUTCOME MEASURES: Lower trapezius (LT) and serratus anterior (SA) muscle activity was measured when subjects performed the four exercises.
RESULTS: Muscle activity was significantly different among the four exercise positions (p<0.05). The backward rocking diagonal arm lift elicited significantly greater activity in the LT muscle than did the other exercises (p<0.05). The backward rocking arm lift showed significantly more activity in the SA muscle than did the other exercises (p<0.05).
CONCLUSIONS: Clinicians can use these results to develop scapular posterior tilting exercises that specifically activate the target muscle.