Physical exercise may be used by physical therapists when dealing with either healthy individuals or with a variety of conditions. Physical therapists can be trained for aerobic exercise for people of all ages. How does the Physical Therapist define FITNESS? Fitness is a general term used to describe physical work capacity. Cardiorespiratory control, muscle strength, and endurance, and musculoskeletal mobility are required to perform physical work. Also included in the definition of fitness is optimal body composition. In order to become physically fit, individuals must participate regularly in some form of physical activity that uses large muscle groups and challenges the cardio-respiratory system. Individuals of all ages can improve their overall fitness status by participating in activities such as walking, biking, running, swimming, climbing the stairs, cross-country skiing and/or weight training. Fitness levels can be described on a continuum from poor t...