versus caloric expenditure and the role played by physical activity (Cutler et al. 2003). Resolving this debate, however, is not the primary purpose of this study. The focus is on understanding what effects the built environment may have in fostering sedentary behavior, the strength and magnitude of these effects, and opportunities and incentives to encourage greater physical activity.
The effects of the built environment on physical activity levels operate through a complex set of relationships. Figure 1-1 shows the committee’s conceptualization of the key connections. The starting point is the individual, with all the demographic characteristics, genetic components, lifestyle and other preferences, and time