Prescribing exercise for cardiac patients is comparable in many ways to prescribing medications; that is, one recommends an optimal dosage according to individual needs and limitations. For in-patients, simple exposure to orthostatic or gravitational stress can obviate much of the deterioration in exercise tolerance that normally follows a cardiovascular event or intervention. On the other hand, the continuum of exercise therapy for outpatients may range from brisk walking to marathon running. Upper body and resistance training also have been shown to be safe and effective for clinically stable patients. Moderate intensity exercise training can produce beneficial changes in functional capacity, cardiac function, coronary risk factors, psychosocial well being, and possibly improve survival in patients with coronary artery disease. These findings may be especially relevant for the previously sedentary patient, in whom the subjective discomfort of vigorous exercise may serve as a deterrent to long-term compliance with physical training. (c) 2000 by CHF, Inc.