Fitness After 40: Your Strong Body at 40, 50, 60, and Beyond

by Vonda J. Wright

Loss of functional independence before age 75, therefore, is most likely the result of disease, disuse, genetic predisposition, or destructive lifestyle habits.

On a genetic level, you are programmed to move. Your body does not know whether you are hunting and gathering right outside your cave or traveling long distances to find food. Your body simply knows it is moving. And moving keeps the genes that transcribe for health, mobility, muscle, and bone health turned on. If your body perceives that you are just sitting around, it thinks you are waiting for winter to be over and your metabolism goes into hibernation mode.