Prevalence, trends and environmental influences on child and youth physical activity

The purpose of this chapter was to describe prevalence and trends in children's physical activity (PA) and to overview the evidence of relationships between the broader neighborhood social and physical environment and child and youth PA. PA typically declines throughout childhood and adolescence. Few countries describe prevalence estimates of the proportion of children and youth meeting current PA recommendations; however, trends suggest declines in population level PA among children, in particular declines in active transport and school physical education. While reasons for these changes are not well-understood, there is an increasing research focus on the influence of the neighborhood social and physical environment as possible determinants of these declines. Literature examining associations between the broader social and physical environment and child and youth PA identified factors such as safety concerns (e.g. road safety, crime and concerns about strangers), social interaction (e.g. child visits with peers, neighborhood relationships, other children live in neighborhood close by), and urban design (e.g. connectivity of streets, access and availability of public open spaces and sports facilities) as important influences. However, much of the evidence is preliminary and context specific. That is, studies that reported null associations with children's PA used global rather than context-specific measures of PA (e.g. walking in the neighborhood). Future research requires better conceptualization of the social and physical environment in which children live and consideration of context-specific behaviors and behavior-specific aspects of the environment relevant to children and youth. Prospective studies are needed to establish temporal relationships between the social and physical environment and child and youth PA.