Effectiveness of a Posterior Shoulder Stretching Program on University-Level Overhead Athletes: Randomized Controlled Trial.

Abstract

To determine whether a posterior shoulder stretch was effective in increasing internal rotation (IR) and horizontal adduction (HAd) range of motion (ROM) in overhead athletes identified as having reduced mobility. Randomized controlled trial (parallel design). University-based sports medicine clinic. Thirty-seven university-level athletes in volleyball, swimming, and tennis, with IR ROM deficits ≥15°, were randomized into intervention or control groups. No subjects withdrew or were lost to follow-up. The intervention group performed the "sleeper stretch" daily for 8 weeks, whereas the control group performed usual activities. Independent t tests determined whether IR and HAd ROM differences between groups were significant at 8 weeks and 2-way repeated-measures analysis of variance tests measured the rate of shoulder ROM change. Subject-reported shoulder pain and function were obtained at each evaluation. Significant differences were found between the intervention and control groups' IR and HAd ROM at 8 weeks (P < 0.001 and P = 0.003, respectively) compared with baseline (zero weeks) (P = 0.19 and P = 0.82, respectively). Significant improvements in IR were detected in the intervention group at 4 weeks (P < 0.001), whereas HAd demonstrated significant changes only at 8 weeks (P = 0.003). Reported shoulder function (P = 0.002) was different between study groups at 8 weeks. Overhead, university-level athletes with an IR deficit ≥15° significantly increased their IR and HAd ROM after performing a posterior shoulder stretch for 8 weeks. Effective management of posterior shoulder tightness through stretching may reduce the incidence of shoulder pathology in overhead athletes.