An apparatus is designed to provide support and correct form in order to perform rotator cuff strengthening exercises, either for rehabilitation or prevention of injury. In an exemplary embodiment, a cuff holds a person's elbow fixed at a position substantially perpendicular to curved plate secured to and parallel to a person's vertical (i.e., longitudinal) axis at the person's torso, which helps isolate internal and external rotation of the humerus and reduce any compensatory motions that can occur when the elbow is not supported. This optimally strengthens these important shoulder movements which in turn allows athletes to improve their upper extremity strength.
