Exercise

James M. Rippe, M.D is a best-selling author, world-renowned cardiologist, and founder of the Rippe Lifestyle Institute.  He explains that if you look at all the risk factors for dying, the one that is most predictive is fitness level. In addition, an older person with high cardiovascular fitness is healthier than a younger person who is physically inactive. By increasing your fitness level, you can actually roll back your biological clock.