Explain the term "physical activity environment …

Human behaviors vary in their dependence on specific places. Physical activity is arguably on the more place-dependent end of the spectrum. Some places are physical activity–friendly by nature or design, such as playgrounds, health clubs, open spaces, stairs, sidewalks, and trails. Other places are designed for sedentary behaviors, such as movie theaters, classrooms, offices, and elevators. Places also can be designed in such a way that physical activity is unsafe or unattractive, such as interstate highways, streets without sidewalks or protected pedestrian crossings, crime-infested parks, and locked stairwells.

Given the close connection between built environments and physical activity, one might expect a long history of incorporating built environmental measures in physical activity research. In fact, very few studies of physical environments and physical activity were conducted until the mid-1990s, at least in health-related fields. The primary reason for this neglect of physical environments was probably reliance by researchers on the dominant models and theories of behavior, which emphasized psychological and social influences on behaviors but did not specifically incorporate physical environmental influences.

Increasing use of ecologic models of behavior in the 1990s by physical activity investigators made it clear that important categories of influences had been neglected. Ecologic models are distinguished by their emphasis on multiple levels of influence on behaviors, including individual (biological, psychological); social/cultural; organizational; community; physical environment; and policy.1 Ecologic models directed investigators to consider physical environment and policy influences, and physical activity–specific ecologic models made it clear that specific physical environmental variables of relevance to physical activity had to be conceptualized and measured before they could be examined in studies.2 Thus, the history of physical environment measures for use in physical activity research is brief.