Running is not simply for the young and healthy. Older runners with healthy joints can keep pounding the pavement well into old age.
Contrary to what some might think, researchers now say after 21 years of study that if you're healthy and generally injury free, there are few reasons to put away your running shoes as you age, even into your 70's and 80's.
Sports medicine experts say healthy joints and muscles respond well to appropriate stressing, but the key is to listen to your body.
The biggest risk that runners will face as they age with regard to injury is over training.