Good advice

I think the impressive thing here is the 4-5 miles of hard running, 4-5 days per week for 50 years. Clearly the exercise program was effective. This sounds like one of those cases where the running did far more good than injury. But the author makes a good point: be sure to listen to the body and shift to more low-impact forms of exercise when your body calls for it.

With two new knees, my exercise advice
Plain Talk By Al Neuharth, USA TODAY Founder

Joint surgery has become common for those who are restricted in exercising, walking or working. There were 550,161 knee replacements across the USA in the last year for which figures are available (2007).

Having had both my knees replaced last week, I've had time to think about what I might have done to avoid or delay my problem and how you might handle yours.

It's all about the right kind of exercise. My three stages:

I've been a physical fitness nut ever since I got out of the Army after World War II at age 22. Four or five miles of hard running became my routine four or five days a week for over 50 years.

That routine helped keep me fit and helped keep my weight between 162 and 169 all those years. (It was 166 when I got out of the Army.)

But about 10 years ago at age 75, the regular running — on streets, sidewalks, running paths or even sandy beaches — started becoming painful. So I switched to a treadmill, later an elliptical trainer and finally a crosstrainer.

My surgery was done at the renowned Mayo Clinic at its Jacksonville branch near my Cocoa Beach home. I requested to have both knees done at the same time, partly because former first lady Barbara Bush had that done successfully at Mayo in Rochester, two years ago. I had admired her common sense and judgment, both politically and personally, when she was in the White House.

Dr. Mark P. Brodersen, a low-key Midwesterner (from Iowa) did my surgery. He's done hundreds, including a half-dozen double-knee jobs last year.

Now recovering at the Sea Pines Rehabilitation Hospital in Melbourne, Fla., I'm dedicated to the kind of more limited physical exercise I should have started years ago. Before your knees get too old, maybe you should be, too.

Other views on knees and exercise

"You have to care for the meniscus in your knees, which breaks down as you age. Keep exercising, but choose low impact activities like walking, and take Vitamin D, which helps calcium absorption."

— Mehmet Oz, host, The Dr. Oz Show

"Runners with normal knees don't have an increased risk of developing osteoarthritis. If Mr. Neuharth was able to avoid obesity — which does cause it — by running, he's way ahead of the game."

— Ralph Gambardella, M.D., president, Kerlan-Jobe Orthopaedic Clinic