Objective: To determine if the lower trapezius muscle responds to scapular retraction exercise in ranges of motion available to rotator cuff repair patients in the first two weeks following surgery. Study design Randomized repeated measures. Setting Biomechanics laboratory in a University setting. Participants Twelve healthy women and eight men free of rotator cuff pathology. Main outcome measures: Integrated (iEMG) and normalized EMG values. Results: ANOVA revealed a main effect and follow-up comparisons showed that mean iEMG values of the lower trapezius, infraspinatus, and upper trapezius were on average 65% greater for the 130° condition. For the 90° condition, the normalized values of the lower trapezius and deltoid were 40·3% and 7·2% of the 130° condition respectively. Conclusions: These findings suggest the lower trapezius muscle is more active in the 130° condition. Normalised iEMG data for the 90° condition suggest the lower trapezius muscle can be recruited in a range of motion attainable for acute rotator cuff repair patients.