Systematic literature review on built environment effects on physical activity and active transport - an update and new findings on health equity

Smith, M., Hosking, J., Woodward, A., Witten, K., MacMillan, A., Field, A., … Mackie, H. (2017). Systematic literature review on built environment effects on physical activity and active transport - an update and new findings on health equity. International Journal of Behavioral Nutrition and Physical Activity, 14. http://dx.doi.org/10.1186/s12966-017-0613-9

Built environment interventions show promise of increasing physical activity levels in children and adults but further research is needed to understand inequitable access to infrastructure improvementsThis systematic review of the literature had two primary aims: (1) to identify which environmental interventions increase physical activity in residents at the local level, and (2) to build on the evidence base by considering intervention cost and the differential effects of interventions by ethnicity and socioeconomic status. The review included 28 quantitative empirical studies investigating the relationship between objectively measured built environment feature(s) and physical activity and/or active transport in children and/or adults.

Environmental interventions associated with increased physical activity included (a) improvements in neighborhood walkability, (b) the provision of quality parks and playgrounds, and (c) the installation of or improvements in active transport infrastructure. Some evidence indicated that socioeconomically advantaged groups benefitted more from infrastructure improvements than other groups. While the research showed that both children and adults benefitted from the environmental interventions, research on children and older adults was scarce. The research on the impact of environmental interventions on cycling behaviors was also scarce.

The Evaluation of Public Health Practice Projects Quality Assessment Tool (EPHPP) was used with each study to assess strength of evidence. Results indicated that the evidence was weak for three-quarters of the studies, due primarily to lack of representativeness and generalizability. The overall findings, however, support the understanding that built environment interventions can improve physical activity behaviors across a population. This understanding is consistent with previous systematic reviews.

Specific built environment interventions showing promise of increasing active transport and physical activity levels in children and adults include crosswalk and sidewalk improvements, improved bike parking, installation of traffic calming features, new greenways, traffic free bridges and boardwalks, the installation of fitness/playground equipment, park renovations, and increased land use mix.

The researchers acknowledge that, while this review focused only on objectively assessed built environment features, people’s perceptions on the relationship between the built environment and activity behaviors could also play an important role in how active they are. The researchers also acknowledge that the adult-centric approach to characterizing built environments may not be sufficiently capturing environments that matter to children and youth. The authors highlight the importance of further research to investigate the possibility that the benefits of built environment improvements may not be equitably distributed.

The Bottom Line

Built environment interventions show promise of increasing physical activity levels in children and adults but further research is needed to understand inequitable access to infrastructure improvements