Prescribed, supervised exercise training has proved valuable in the rehabilitation of selected coronary patients. However, long distance (marathon) running has limited cardiovascular value in the rehabilitation of patients for a majority of occupations, which involve predominantly upper extremity effort. The age of patients with coronary heart disease and the severity of the lesions preclude the wide application of marathon running to the general coronary heart disease population. Less than 6/1000 subjects with coronary heart disease have been estimated as potentially being able to achieve by high-level training a maximum Vo2 sufficient to complete a marathon race in 5 hours. The hazards of high-level-activity-induced cardiac arrest that is reversible mandates the availability of CPR equipment and personnel in the immediate vicinity of all coronary patients and most coronary-prone patients who are undertaking such heroic activity. Over-publicized marathon running by a few subjects has aroused unrealistic expectations for the majority of coronary heart disease subjects and probably similarly for a considerable number of coronary-prone subjects, many of whom have "silent" coronary disease.