A growing body of evidence has shown that regular physical activity is associated with a range of health benefits, such as decreased risk of type 2 diabetes, metabolic syndrome, cardiovascular disease, stroke, and several types of cancers, as well as premature mortality. To prevent chronic diseases, the current guidelines for physical activity recommended that adults carry out ≥150 min/week of moderate-intensity physical activity. However, less is known about whether light-intensity activities also have such benefits, and whether sedentary behavior is an independent predictor of increased risks of these chronic diseases, as imprecise assessments of these behavior and cross-sectional study designs have limited knowledge to date.

Recent technological advances in measurement methods have made the use of wearable device, such as the accelerometer, feasible for use in longitudinal and large-scale epidemiological studies. This is a relatively new field of research. Several previous studies were collected objectively measured physical activity with the aim of relating these to the clinical health outcomes.

Therefore, in this presentation, we will present data on the health effects of objectively assessed physical activity, light intensity physical activity, and sedentary behavior collected in a large epidemiological studies using data from National Health and Nutrition Examination Survey (n= ~5300), and Smart Wellness City study (n= ~6000). We also compared objectively measured physical activity with those data measured using questionnaires.

Assessment of physical activity using wearable devices such as accelerometers will be more widely used in large-scale epidemiological studies and clinical studies. Also the importance of collecting data on the health effects of these objective physical activity parameters will become apparent from large epidemiological studies.