We know that running is good for your heart, but what most people don’t know is that the health benefit appears to level off at a particular frequency of exercise. What’s the tipping point? That’s what researchers at the University of South Carolina and the Ochsner Health System, in New Orleans, have been trying to figure out, and they recently offered their conclusion to health physiologists at a meeting of the American College of Sports Medicine. HealthDay reports that the researchers, who analyzed the link between running and cardiovascular-related deaths in nearly 53,000 adults, found that running lowered the risk for mortality when a person did not exceed more than 20 miles a week, log more than five to seven miles per hour, or run more than two to five times a week. Running more miles or at greater speed was not not associated with worse outcomes when compared with non-runners, but it did seem to mitigate the advantage gained at lower doses of running. Read more from HealthDay.