Comparative Effects of Blood Flow Restriction and Traditional Strength Training on Proximal Shoulder Musculature: A Randomized Clinical Trial

Blood Flow Restriction (BFR) training may be an alternative when traditional heavy-load training is unsuitable. This study compared BFR with light loads to traditional strength training for shoulder muscle development proximal to the occlusion site; Methods: A total of 22 healthy adults were randomized into Group A: BFR training (30% 1RM; <i>n</i> = 12) and Group B: Traditional strength training (70% 1RM; <i>n</i> = 10). Four-week protocol (2 sessions/week) included shoulder abduction and lateral rotation, and dumbbell overhead press. Arm circumference, Single Arm Seated Shot-Put Test (SAASPT), vertical lift strength (VLS) and Shoulder Endurance Test were assessed at baseline and at the end of the protocol. Cohen's d effect size was calculated for significant outcomes; Results: Significant gains occurred in both groups across most parameters. The magnitude of effects was, in Group A, large on Arm circumference and SASSPT (Cohen's d = 0.870 and 1.158, respectively) and very large in VLS and SET (Cohen's d = 1.284 and 1.301, respectively). In Group B, the magnitude of effects was large in SASSPT and VLS (Cohen's d = 0.962 and 0.922, respectively) and very large in SET (Cohen's d = 1.238); Conclusion: BFR training with light loads effectively improved musculature proximal to the occlusion site, demonstrating comparable strength gains to heavy-load training in healthy individuals.