The muscles of the rotator cuff provide stability to the shoulder joint during all movements of the shoulder and arm. Therefore, it’s necessary to strengthen the rotator cuff muscles to develop and maintain optimal function. Here, Merrithew® Master Instructor Trainer Wayne Seeto explains how to use Toning Balls™ and the Halo® Trainer Plus to create higher-level eccentric, concentric and perturbation training exercises to target the rotator cuff while adding challenge to the entire torso.