Abstract
CONTEXT: Athletic trainers use clinical pain and range of motion (ROM) to gauge recovery after musculoskeletal injury. Limited evidence to date suggests which shoulder ROM measures can predict symptomatic relief and functional recovery after delayed-onset muscle soreness (DOMS). OBJECTIVE: To determine whether shoulder passive internal rotation, passive external rotation, active abduction, and active flexion and evoked pain with abduction are associated with resting pain experienced after exercise-induced DOMS. DESIGN: Descriptive laboratory study. SETTING: Controlled research laboratory. PATIENTS OR OTHER PARTICIPANTS: A total of 110 healthy, right-hand-dominant participants (44 men: age = 25.39 ± 7.00 years, height = 178.93 ± 7.01 cm, weight = 78.59 ± 14.04 kg; 66 women: age = 22.98 ± 6.11 years, height = 164.64 ± 6.94 cm, weight = 61.86 ± 11.67 kg). INTERVENTION(S): Participants completed an exercise-induced DOMS protocol for the external rotators of the dominant shoulder to replicate muscle injury. MAIN OUTCOME MEASURE(S): Current resting pain was assessed daily for 96 hours using the Brief Pain Inventory. We evaluated functional recovery with measures of ROM in abduction, internal rotation, external rotation, and flexion. Evoked pain with active abduction was reported, and the pain rating served as the dependent variable in the regression model. RESULTS: Impairment measures explained resting pain at 48 (R2 = 0.392) and 96 hours (R2 = 0.164). Abduction and internal-rotation ROM and evoked pain with abduction predicted resting pain at 48 hours (P < .001). At 96 hours, evoked pain with abduction of the injured arm (P < .001) was the significant contributor to resting pain. CONCLUSIONS: These models suggest that resting pain after experimentally induced DOMS occurs at 48 hours and is associated with specific ranges of motion and evoked pain with abduction.