1. Sketches from The Lancet
2. Centers for Disease Control and Prevention. Safe USA: Walking Safely. Available at: http://www.cdc.gov/safeuse/walk/walking.htm. Accessed July, 2004
3. Office United States Department of Health and Human Services, Healthy People 2010, 2nd ed. Understanding and Improving Health and Objectives for Improving Health. Washington, DC: U.S. 2000. Available at: http://www.healthypeople.gov/ Accessed July 2004
4. Centers for Disease Control and Prevention. Overweight and Obesity. Available at: http://www.cdc.gov/nccdphp/dnpa/obesity/. Accessed July, 2004