AbstractThe history of exercise science reveals that at least three scientists received the Nobel prize for investigations in exercise physiology. The work of these men and their contemporaries was concerned with physiological mechanisms and work performance, not directly with health. Hippocrates and other physicians and philosophers of the ancient world believed that regular physical activity contributed to health and longevity. However, it was only during the last 30–40 years that the focus of exercise research shifted to a study of the impact of physical activity on health and disease. The reason for this change in research emphasis is due to the fact that a) chronic disease is associated with life‐styles, b) people are less active in the Western world, c) prevention is perhaps the ultimate answer to the maintenance of health, and d) chronic disease frequently begins in childhood. A summary of our knowledge concerning the effects of exercise is presented. Because former college athletes have engaged in strenous sports training in their youth, they are of particular interest in this regard. Results of many investigations indicate that former college athletes live about as long as their classmates, and die at about the same rate from heart disease. Former athletes come from larger families, gain less weight after college up to the age of 55 years, are more active in life, and are more likely to be smokers and/or drinkers than their former college classma