Physical activity is an important determinant of both physical and psychological health. Regular physicalactivity exerts beneficial effects on onset and progression of a number chronic diseases, well-being, and haspositive effect to communities and societies. Unfortunately, more than 60% of world wide adults do not reachthe recommended levels of physical activity. This paper presents the prevalence, health risks, and economiccosts of physical inactivity. It also reports the substantial physical and psychological health benefits of regularphysical activity.