The paper examined the role of physical activity and fitness more especially in the area of disease prevention and control by looking at the major ways by which regular physical activity and fitness contributes to optimal health and wellness. The Surgeor General's Report (1996), stressed that physical inactivity is a national problem which contributes to the burden of unnecessary illness and premature death. The emphasis is therefore on moderate physical activity and the focus on integration of physical activity into one's lifestyle which offers additional opportunities for sedentary individuals to improve their health through participation in physical activities that are enjoyable, personally meaningful and fit more easily into daily schedules. There were considerable evidence which showed that the risk of hypokinetic conditions can be greatly reduced among people who engage in regular physical activity to achieve good physical fitness. It was revealed that optimal health is more than freedom from diseases. Therefore people who regularly participate in moderate amounts of physical activity and fitness can live longer and healthier and also, physical activity and fitness not only help prevent illness and diseases, but also promote quality of life.