Running regularly has long been linked to a host of health benefits, including weight control, stress reduction, better blood pressure and cholesterol. However, recent research suggests there is a point of diminishing returns with running. A number of studies have suggested that a "moderate" running regimen of two to three hours per week appears best for longevity. The researchers behind the newest study say people who get either no exercise or high-mileage runners both tend to have shorter life spans than moderate runners. Learn more