Physical activity: a synopsis and comment on "community-wide interventions for increasing physical activity".

In this synopsis, we summarize and comment on Baker and colleagues' Cochrane review of studies on the population-level impact of community-wide physical activity (PA) interventions. Insufficient PA remains a major public health problem. Community-wide interventions offer an opportunity to extend reach by increasing the proportion of the population experiencing the intervention. A previous Cochrane review of community-wide PA interventions concluded that evidence for effectiveness was mixed. Hence, Baker and colleagues incorporated new data about community-based PA interventions. This Cochrane review concluded there is an overall lack of evidence that community-wide interventions improve PA outcomes at the population level. Recommendations are that future research should use high quality research design, more explicitly test ways to increase reach, and utilize objective measurements of PA to increase validity. We suggest that future research should first optimize the intervention by systematically evaluating treatment components and selecting a maximally efficient and effective treatment package.