'Use it or lose it'

If you don’t use it, you’ll lose it. I bet I’ve heard and repeated this age-old aphorism a million times. But can it be over-used?

The adage about using it certainly fits when trying to enhance wellness for all sorts of medical systems: working the brain with puzzles and conversation helps ward off memory loss; walking fast enough to cause one to huff and puff, keeps the heart and lungs strong; regular sexual activity helps prevent impotence; filling the gut with a high fiber diet keeps the bowels in shape and makes you a regular sort-a-guy.

But what can you do when it hurts to move those old...