The exercise shown is part of an exercise program for throwers. To perform the exercise, the patient stands with shoulder flexed to 90 degrees and elbow bent to 90 degrees holding a small Plyoball. The patient then externally rotates their shoulder rapidly, throwing the Plyoball to a partner or against a wall. The partner throws the ball back and the thrower catches the ball as it crosses their body, decelerating their arm and returning it to the starting position, and then quickly repeating the motion.
