How Much Exercise Is Too Much?

His shaven head glistening with sweat, Jeff springs from a lunge position and rams into my stomach. I hit the ground with a ka-thunk, and he drops onto my chest. We tussle. He cocks his right leg (the one with the scorpion tattoo on the calf) and stabs his knee into my ribs. I let out an oomph, and retaliate by clasping my hands behind his neck and squeezing down as hard as I can. We've been at it for nearly three minutes. Sweat seeps from every pore, soaking the mat. My heart is pounding, and I'm gasping for air. Jeff breaks free of the headlock. He jumps up, lunges again, crashing into me like a 220-pound brick. We roll several yards, arms and legs flailing, each trying to tie the other in a knot. Just as I think I can't go another second, the bell rings. We take a one-minute break. And then start all over again.

I know darned well that I'll have a hard time getting out of bed the next morning.

I'm not asking for pity. I do martial arts, which includes "grappling," of my own free will. For whatever bizarre psychological reasons, I like it. So what if my regular opponent outweighs me by 20 pounds? I have 20 years on him. Fair is fair.

Sometimes though, seriously, I wonder just how hard a 50-year-old, father-of-two, sometimes financial planner, sometimes book author and magazine journalist, should be pushing himself. My inevitable injuries don't seem to be healing as fast as they once did -- I have a shoulder that has been hurting for two months now, ever since Jeff decided one afternoon to bend that arm into a pretzel. My wind isn't what it once was. And when my dad was just a few years older than I am now, he had his first balloon angioplasty. Perhaps what I'm doing doesn't only look idiotic -- maybe it really is idiotic.

Should I give up the martial arts and perhaps take up tennis? Shuffle board? B-I-N-G-O?

First, I'm going to do some research.

Before I share that research with you, let me warn those of you born prior to 1965 or so that what you're about to see isn't all joyous. "There are inevitable degenerative processes that occur after a certain age. That's why you don't see many professional athletes over 40; the body simply can't take the abuse," says Gerald Varlotta, D.O., director of sports rehabilitation at the NYU Hospital for Joint Diseases and the Rusk Institute in New York City.

Those degenerative processes include (I'll keep this list short so that older readers don't get too depressed) ...

• Muscles shrink and lose mass

• Joint tendons lose water, making them less flexible and more susceptible to stress

• The heart becomes less able to pump blood quickly

• Bones become less dense, more breakable

• Cartilage starts to break down, and knees, shoulders and elbows become more easily inflamed

"The good news is that much of this process can be delayed with regular exercise -- although exercising in the wrong way can backfire," says Dr. Varlotta.

Uh-oh. It sounds like the medicine man may be telling me to give up martial arts. So I ask him point blank. "It's okay to have a 25-year-old mind in a 50-year-old body, but we sometimes need to lower our expectations," says Dr. Varlotta, matter-of-factly, as he reveals himself to be roughly the same age I am. "We need to use our wisdom and apply it to our physical well-being. And that means exercising smart, sometimes going slow, and being especially cautious of any discomfort."

With that wisdom and restraint, says my stethoscoped contemporary, the middle-aged athlete -- while he or she is unlikely to win world events -- can sometimes shock the world.

Below a few tips from Dr. Varlotta and others on smart exercise for those 40+ ... .

Check your heart. Over 40? Get a complete physical before embarking on any vigorous exercise program -- that's especially true if you, like me, have any family history of heart disease. Know the signs of heart trouble -- which include, but are not limited to chest pain, dizziness, and palpitations -- and call your doctor right away if any occur. (For a more complete listing, see www.americanheart.org.)