Assessment of Physical Activity in Nutritional Epidemiology

Abstract This chapter first discusses conceptual definitions and terminologies that are commonly used in the physical activity literature. Next it reviews reference measures of energy expenditure and objective and self-reported methods for measuring physical activity. Then it describes validation studies of physical activity questionnaires that have been used in large epidemiologic studies. Finally, it discusses methodological issues in the analysis of physical activity and disease risk, including measurement error correction, confounding, reverse causation, and isotemporal analysis.