Forward Shoulder Posture in Collegiate Swimmers: A Comparative Analysis of Muscle-Energy Techniques

Abstract

Context: Empirical data for treating forward shoulder posture supports stretching the anterior shoulder musculature. Although muscle-energy techniques (METs) have been hypothesized to lengthen muscle, no data have described the usefulness of this technique among swimmers.

Objective: To determine if an MET provides improvements in resting pectoralis minor length (PML), forward scapular position, and scapular upward rotation in female collegiate swimmers.

Design: Controlled laboratory study.

Setting: Athletic training room.

Patients or other participants: Thirty-nine asymptomatic National Collegiate Athletic Association Division I women's swimmers (19 experimental, 20 control).

Intervention(s): The experimental group received 2 treatment sessions per week for 6 weeks. The control group received no intervention during this 6-week period.

Main outcome measure(s): We administered pretest and posttest measurements for PML, forward scapular position, and scapular upward rotation in positions of rest and 60°, 90°, and 120° of humeral elevation. The MET consisted of a 3-second stretch in the direction of the pectoralis minor fibers, followed by a 5-second isometric horizontal adduction contraction at 25% of maximum force. Immediately after this contraction, the entire sequence was repeated with the muscle being stretched to the new endpoint. A total of 4 cycles of MET were continuously applied per treatment session twice per week for 6 weeks. We conducted 1-way analyses of covariance to determine any between-groups postintervention test differences.

Results: The MET group had a greater increase in PML postintervention (P = .001, effect size = 1.6) and a greater decrease in forward scapular position postintervention (P = .001, effect size = 1.07) compared with the control group. No differences were found for scapular upward rotation (P > .10).

Conclusions: Our results indicate that 6 weeks of MET treatments applied to the pectoralis minor of asymptomatic female swimmers provided improvements in PML and forward scapular position compared with a control group.

Keywords: injury prevention; manual therapy; scapular kinematics.

Figures

Figure 1.

Measurement of pectoralis minor length.

Figure 2.

Measurement of forward position of the scapula.

Figure 3.

Measurement of scapular upward rotation.

Figure 4.

Muscle-energy technique for the pectoralis minor.