Background: Traumatic full-thickness rotator cuff tears are typically managed surgically, followed by rehabilitation, but the load progression to reach an optimal clinical outcome during postoperative rehabilitation is unknown. Purpose: To evaluate whether there was a superior effect of 12 weeks of progressive active exercise therapy on shoulder function, pain, and quality of life compared with usual care. Study Design: Randomized controlled trial; Level of evidence, 1. Methods: Patients with surgically repaired traumatic full-thickness rotator cuff tears were recruited from 2 orthopaedic departments and randomized to progressive active exercise therapy (PR) or limited passive exercise therapy (UC [usual care]). The primary outcome was the change in the Western Ontario Rotator Cuff Index (WORC) score between groups from before surgery to 12 weeks after surgery. Secondary outcomes included changes in the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire score, pain, range of motion, and strength. Adverse events were registered during the intervention period. Results: A total of 82 patients were randomized to the PR (n = 41) or UC (n = 41) group. All 82 patients (100%) participated in the 12-week assessment and 79 in the 1-year follow-up. At 12 weeks, there was no significant difference between the groups in the change in the WORC score from baseline adjusted for age, sex, and center (physical symptoms: P = .834; sports and recreation: P = .723; work: P = .541; lifestyle: P = .508; emotions: P = .568). Additionally, there was no between-group difference for the secondary outcomes including the WORC score at 1 year and the DASH score, pain, range of motion, and strength at 12 weeks and 1 year. Both groups showed significant improvements over time in all outcomes. In total, there were 13 retears (16%) at 1-year follow-up: 6 in the PR group and 7 in the UC group. Conclusion: PR did not result in superior patient-reported and objective outcomes compared with UC at either short- or long-term follow-up (12 weeks and 1 year). Registration: NCT02969135 ( ClinicalTrials.gov identifier)