Most people have a tendency to stop moving around and live a more sedentary lifestyle as they get older, but exercise is an important and beneficial practice no matter what your age. For instance, researchers found exercises that boost strength and agility may help elderly women with brittle bones lessen their odds of falling. Women between the ages of 75 and 85, all of whom had reduced bone mass or full-blown osteoporosis, lowered their fall risk with strength training and agility activities. So even older adults with brittle bones from osteoporosis, a group who may avoid exercise because of safety concerns, should be active, under the proper supervision. As I've said in the past, it's never too late to start exercising!
Journal of the American Geriatrics Society May 2004;52(5):657-65