I never even think about it and while don't ride mega distances I do a lot of climbing and push if for all I'm worth quite a bit. Figure I'm keeping things healthy by staying as fit as I can.
From an article on an extensive study that appeared in the JAMA last year. Not exercising worse for your health than smoking, diabetes and heart disease, study reveals.
"There is no level of exercise or fitness that exposes you to risk," he said. "We can see from the study that the ultra-fit still have lower mortality."
"In this study, the most fit individuals did the best," said Metzl, who was not involved in the study. "Once cleared by their physicians, patients shouldn't be afraid of exercise intensity."
It is a great article and well worth a few minutes to read it if you have time. Since we are all somewhat physically active I have to assume, it will make you feel
great about all that work you've been putting in.