A sedentary life style is recognized as a risk factor for poor health. More and more people are becoming less active because they believe that they do not have enough time for the activities they would do to derive health benefits. Inactive people who develop a healthy life style by improving their physical fitness are less likely to die from all types of causes and of cardiovascular disease than are those who remain sedentary. Whether it is in minimal or maximal amounts, exercise is the key to a long and healthy