Study: age affects mind, body

The brain decline affects how speedily brain cells fire off commands to muscles. The study finds that in middle age even healthy people begin to lose some of the insulation in a motor-control part of the brain. The research helps explain why it's hard to be a world class athlete after 40.

As depressing as that might sound, researchers say an exercised brain may signal for repair cells to get to work.

So, keep active, take care of your body and watch what you eat.