Physically active men and women may be less likely than their sedentary peers to become overweight. Caloric restriction in overweight persons produces larger weight losses than does exercise, although more of the weight loss by dieting is from lean body mass. The addition of exercise to diet intervention produces more weight loss than does dieting alone. Exercise has a favorable effect on body fat distribution, with a reduction in waist-to-hip ratio with increased exercise. Exercise is especially important in maintaining weight loss in overweight persons. Several prospective studies have shown that overweight men and women who are active and fit have lower rates of morbidity and mortality than overweight persons who are sedentary and unfit. Therefore, exercise is of benefit to overweight persons, even if it does not make them lean. Exercise is recommended as an important part of a weight control program.