1. US Dept of Health and Human Services. Healthy People 2010: Understanding and Improving Health. 2nd ed. Washington, DC: US Government Printing Office; 2000.
2. Humpel N, Owen N, Leslie E. Environmental factors associated with adults' participation in physical activity: a review. Am J Prev Med. 2002;22:188-199.
3. King AC, Bauman A, Calfas K. Innovative approaches to understanding and influencing physical activity. Am J Prev Med. 2002;23(suppl):1-108.
4. Orleans CT, Kraft MK, Marx JF, McGinnis JM. Why are some neighborhoods active and others not? Charting a new course for research on the policy and environmental determinants of physical activity. Ann Behav Med. 2003;25:77-79.
5. Saelens BE, Sallis JF, Frank LD. Environmental correlates of walking and cycling: findings from the transportation, urban design and planning literatures. Ann Behav Med. 2003;25:80-91.