Despite the dissemination of health information promoting the benefits of a physically active lifestyle the majority of Americans either engage in exercise behavior on an infrequent basis or are completely sedentary. Physical activity participation decreases over the life span By age 21,only 42% of male and 30% of female report participating in vigorous physical activity on a regular basis participation decreases with increasing age, and only 10% american adults as a whole engage in regular vigorous physical activity and most are sedentary or sporadically active. Only 22% of American adult participate in regular moderate physical activity.