Connecting active living research and public policy: transdisciplinary research and policy interventions to increase physical activity.

National and international organizations recommend creation of environments that support physical activity where people live, work, play, study, and travel. Policy changes can lead to activity-supportive environments and incentives. Research on environmental and policy influences on physical activity is well underway in many countries. An important use of the research is to inform policy debates, but the "translation" of research to policy is an emerging science. The papers in this supplement were presented at the 2008 Active Living Research Conference whose theme was "Connecting Active Living Research to Policy Solutions." The papers include evaluations of policy initiatives and research that suggests promising new policies. Commentaries propose principles for improving the translation of research to policy. Improving the rigor of research, asking policy-relevant questions, presenting country-specific data, and effectively communicating findings to policy makers are likely to contribute to greater impact of research on policy processes.