A Dose-response Relationship Between Types Of Physical Activity And Physical Fitness

Abstract

PURPOSE: The purpose of this study was to investigate the relationships of physical activity(sedentary activity and non-sedentary activity) with muscle strength and cardiorespiratory fitness. METHODS: For this study, 409 adults(muscle strength: 409, cardiorespiratory fitness: 266) were interviewed using a standard questionnaire. The questionnaire was modified from a physical activity questionnaire that was used for the Stanford 5 city project, which included work, household, and leisure activities. There were four types of physical activities that were included sleep(1 MET), five different sedentary physical activity(1.0~1.4 MET), non-sedentary activity(OPA and LTPA), and only leisure-time physical activity(LTPA). Specifically for the non-sedentary activities and the LTPA were classified into three categories(moderate: 3~4 MET, hardly: 5~6 MET severely: 5~6MET) according to the intensity of the activity. All activities were measured by the average amount of hours spent per week performing each activity in the past year. Muscle strength and cardiorespiratory fitness were estimated on a grip strength, leg extension and YMCA step test. We analyzed relationships of physical activity with muscle strength and cardiorespiratory fitness. RESULTS: Muscle strength was associated positively with hardly(r=0.175**, r=0.156**) and severely(r=0.247**, r=0.233**) intensive physical activity, total physical activity(r=0.292**), physical activity per time(r=0.251**). Cardiorespiratory fitness was associated positively with severely non-sedentary activity only female(r=−0.252**, r=0.286**) and total physical activity(r=−0.133**), physical activity per time only female(r=−0.194**). CONCLUSIONS: The type of physical activity may help determine the extent of physical fitness(muscle strength and cardiorespiratory fitness. As results, the promotion of physical activity in adults should emphasize hardly or severely-intensity physical activity and reducing sedentary behavior on daily life.