OK, the results are in. And those of us who are couch potatoes won’t be happy. But after years and years of listening to the drip, drip, drip of facts about everything from weight loss to longevity, we have to say it here: The most youth--restoring move you can make is (drum-roll, please) . . . exercise! It’s the one (virtually risk-free) prescription that has the power to affect every cell and system in your body, reducing your risk of developing dozens of diseases, slowing down aging and adding years to your life, according to a 2010 review published in the International Journal of Clinical Practice. “The benefits are huge, and they are extensive,” says Steven Blair, PED, professor of exercise science, epidemiology and biostatistics at the University of South Carolina, who has been studying the effects of exercise for 44 years. “Being inactive is one of the strongest predictors of mortality—far more important than even obesity.” But with new forms of exercise popping up faster than you can say Zumba, how can you tell which workouts do what? Or if you’re not active by nature, what’s the minimum you can do and still get good results? Here, all the information you need to write your own fountain-of-youth exercise plan.

You want to: Live longer by keeping your heart healthy
Commit to: At least 30 minutes of
moderate-intensity cardio five days a week or 20 minutes of vigorous-intensity cardio three days a week.
Result: Add about four years to your life and reduce your risk of dying from heart disease almost ninefold.
How it works: You can get aerobically fit—and protect your heart—by doing two and a half hours of moderate cardio exercise such as brisk walking or an hour of intense cardio exercise such as running every week, says Samia Mora, MD, assistant professor of medicine and a cardiologist at Harvard Medical School. Mora and her colleagues followed almost 3,000 asymptomatic women after initially testing their fitness levels and heart-rate recovery (how quickly heart rate returns to normal after strenuous exercise). Women who were the fittest and had the best heart-rate recovery (HRR) slashed their risk of dying from heart disease within 20 years almost ninefold compared with their unfit, poor-HRR peers. “About one third of the benefits of physical activity are related to reductions in inflammation, which can contribute to plaque formation and other processes that lead to heart disease,” says Mora. And because heart disease is the number-one killer of adult women, becoming fit can help you live nearly four years longer, according to Dutch researchers.
For a bigger boost: Lift weights.
Research suggests that aerobic exercise may lower levels of C-reactive protein (CRP), an inflammation marker associated with heart disease, only if you lose weight as well. But strength training seems to make a difference regardless. For the best results, combine the two. Previously sedentary adults who did both cardio and strength work for 12 weeks lowered their CRP levels 58 -percent—enough to reclassify them from moderate to low risk for heart disease, according to a study in Medicine & Science in Sports & Exercise. “The body may adapt to the healthy inflammation that weight lifting creates in muscle by decreasing the production of CRP,” says study author Laura K. Stewart, PhD, assistant professor of exercise physiology at Louisiana State University.