Sure, you already know that exercise can help to keep you young. But not all workouts are created equal, according to researchers at the University of South Carolina. When they tracked over 40,000 men and women from ages 20 to 90 they found that swimmers of all ages were 50 percent less likely to die than sedentary folks, walkers or runners. One reason for the trumped up benefit may be the built-in resistance training swimming provides in addition to an aerobic benefit.