Objective: To compare scapular muscle activity in healthy overhead and nonoverhead athletes.
Design: One between (group) and 1 within (exercise) repeated measures.
Setting: Controlled laboratory environment.
Participants: Fifteen overhead sport athletes (10 women and 5 men) and 15 nonoverhead sport athletes (10 women and 5 men).
Interventions: Subjects completed 5 individual trials of a Cuff Link, standard push-up, and supine pull-up while surface electromyography (EMG) recorded muscle activity of 4 scapular muscles on the throwing dominant side. Mean EMG data were normalized to a maximum voluntary isometric contraction.
Main Outcome Measures: Normalized mean EMG.
Results: The upper trapezius was significantly more active (F2,56 = 70.118; P < 0.001) during supine pull-up (61.57 ± 29.67%) than during push-up (27.89 ± 16.21%) and Cuff Link (5.50 ± 2.94%). The middle trapezius was significantly more active (F2,56 = 134.192; P < 0.001) during supine pull-up (62.89 ± 24.17%) than during push-up (21.12 ± 13.10%) and Cuff Link (6.59 ± 4.81%). The lower trapezius was significantly more active (F2,56 = 41.326; P < 0.001) during supine pull-up (60.47 ± 34.80%) than during push-up (34.80 ± 30.81%) and Cuff Link (9.67 ± 4.34%). For upper trapezius, middle trapezius, and lower trapezius, the levels of activation during push-up were significantly greater compared with those during Cuff Link. The serratus anterior was significantly more active (F2,56 = 25.652; P < 0.001) during push-up (49.97 ± 18.86%) and Cuff Link (43.81 ± 19.70%) than during supine pull-up (25.52 ± 19.80%). There were no significant influences of group on muscle activation.
Conclusions: Overhead and nonoverhead athletes elicited similar levels of muscle activation. Differences in muscle activation existed within the 3 exercises. Clinicians should consider the muscle of interest when prescribing one of these exercises.
From the Department of Kinesiology and Physical Education, University of Central Arkansas, Conway, Arkansas.
Submitted for publication September 22, 2010; accepted April 26, 2011.
The authors report no conflicts of interest.
This project received financial support from the University Research Council at the University of Central Arkansas.
Corresponding Author: W. Steven Tucker, PhD, ATC, Prince Center 133C, University of Central Arkansas, Conway, AR 72035 (firstname.lastname@example.org).