Swimming (sport) less stress on joints. Due to continuous rotation and usage, the shoulder (rotator cuff) is the joint most susceptible to injury in swimmers. As opposed to a single incident, injury to the rotator cuff in swimmers is a result of repeated trauma and overuse. The joint is most prone to injury when the arm is repetitively used in a position above the horizontal. This position occurs in each of the four swimming strokes in every cycle of the arms. Of the four muscles and tendons of the rotator cuff, the injury, or tear, is most likely to occur in the
Rotator cuff arm, moving it outward and away from the trunk, the rotator cuff compresses the glenohumeral joint, an action known as concavity compression, in order to allow the large deltoid muscle to further elevate the arm. In other words, without the rotator cuff, the humeral head would ride up partially out of the glenoid fossa, lessening the efficiency of the deltoid muscle. The anterior and posterior directions of the glenoid fossa are more susceptible to shear force perturbations as the glenoid fossa is not as deep relative to the superior and inferior directions. The rotator cuff's contributions to concavity compression and