References
1. The benefits of physical activity. Centers for Disease Control and Prevention. http://www.cdc.gov/physicalactivity/everyone/health/index.html. Accessed July 2, 2013.
2. 2008 Physical Activity Guidelines for Americans. U.S. Department of Health and Human Services. http://www.health.gov/paguidelines/guidelines/default.aspx. Accessed July 2, 2013.
3. Armstrong S, et al. Social connectedness, self-esteem, and depression symptomatology among collegiate athletes versus nonathletes. Journal of American College Health. 2009;57:521.
4. Peterson DM. Overview of the benefits and risks of exercise. http://www.uptodate.com/home. Accessed July 2, 2013.
5. Hannan JL, et al. Beneficial impact of exercise and obesity interventions on erectile function and its risk factors. The Journal of Sexual Medicine. 2009;6(suppl 3):254.
6. Hamilton LD, et al. The roles of testosterone and alpha-amylase in exercise-induced sexual arousal in women. Journal of Sexual Medicine. 2008;5:845.
7. Laskowski ER (expert opinion). Mayo Clinic, Rochester, Minn. July 2, 2013.