The investigators recognize that there is limited evidence regarding the effectiveness and safety of closed-chain exercises in patients with full-thickness rotator cuff tears. Therefore, the investigators are employing several steps to assure safety. At the beginning of each session, each patient will fill out a questionnaire to assess for adverse effects of exercises (such as severe joint pain). After each exercise, participants will rate their shoulder pain level and their perceived difficulty with the exercise. This information will be used to tailor the intervention according to the response to the intervention. Furthermore, it will allow for monitoring for adverse outcomes of the intervention.