Staying physically fit while injured can improve the patient's outlook, both physiologically and psychologically, and help him or her return to regular activities completely, safely, and with decreased risk of re-injury. Although treating and protecting the injured area is of primary concern, it is important to then look beyond the injury, toward keeping the rest of the body as fit as possible. Whether through alternative sports, cross training, or water exercise, the patient can preserve the integrity of the injured joint, keep the noninjured muscles active, and maintain ever-important cardiovascular fitness. The exercise prescription for the injured athlete should emphasize our most vital muscle, the heart.