The questions arise occasionally: How much running is too much? Is running actually bad for your health? Is it stressful on the heart? The questions aren't being asked by serious couch potatoes as an excuse to stay off their feet, but by health scientists, medical experts and long-distance runners who want to make sure they're making the right choices for their bodies.
Among the most curious are the increasing number of health- and fitness-minded individuals and groups attempting to return to our ancestors' roots. These people advocate a lifestyle based on how our hunter-and-gatherer ancestors supposedly lived thousands of years ago: Eating things like grass-fed meats, fish, nuts, seeds and fresh vegetables and fruits, which is the basis of the Paleo or "caveman" diet. In attempting to discern how our early relatives might have lived, people have turned their attention to distance-running and asked the question: Is it really natural? The reasoning is that our ancestors would have had no reason to run long distances – rather, they would need to run in short, intense sprints for the purpose of hunting.
So, is running actually bad for your health? That depends on who you ask. Most people agree that running reasonable distances is excellent exercise provided your body is well-fed and you're in good shape. But what about the endurance runners who seem to take it over the top? After all, the Centers for Disease Control and Prevention recommends that adults get 30 minutes of moderate exercise every day – a far cry from the 10 miles a day that some people run. But getting exercise is very important – it reduces your risk of high blood pressure, diabetes, Alzheimer's, obesity, heart disease and dementia, among other things.
However, according to Dr. James O'Keefe, the director of Preventative Cardiology at Saint Luke's Mid America Heart Institute in Kansas City, we must impose healthy limits on our exercise:
"Your body is designed to deal with oxidative stress that comes from exercise for the first hour," O'Keefe said. "But prolonged intense exercise causes excessive oxidative stress, which basically burns through the antioxidants in your system and predisposes you to problems."
Thus, the best answer is to consult with your doctor to determine what amount of running is right for you. If you have knee or back problems, consider trying other high-intensity exercises like swimming or skating, which are easier on the joints.