Numerous reports indicate that physical inactivity is one of the coronary risk factors; however, proof that exercise has a protective effect is still elusive. Nevertheless, to continue the existing controversy on the prophylactic value of physical activity seems to be inappropriate. On the one hand, a controlled trial is not feasible; on the other hand, physical activity is a physiological function that should be promoted anyway, regardless whether irrefutable evidence of its value in the prevention of coronary heart disease is available. Activity starting in childhood and continuing throughout life is a safe approach. In more general terms, habitual physical activity should be re-introduced into the pattern of life of contemporary society.