Exaaaaactly. Well uh you know? Exaaaaaactly.
Here is the word. Physical activity lowers body fat which in turn lowers serum fats and cholesterols. As a result, heart and vascular disease is profoundly diminished. In addition, physical activity lowers blood pressure which profoundly reduces risk for kidney disease, stroke, and other end organ sclerosis. Now, the study, which I didn't read because it wasn't even linked in the article, notes that 7 mph is considered strenuous. To a lot of people here, no 7 mph is not strenuous, and I would say that these people can continue to run for the rest of their long long long lives! However, overdoing it I believe can be detrimental if it releases too many catecholamines, cortisol, and other stress hormones. If you slowly work into a high level of fitness that is manageable for you, you will see the longer longetivity, but if you routinely put your head through the ringer, you might be undoing the work you put in.