A few years ago, I was rock climbing at the Enchanted Tower, in New Mexico, with my friend Mike, a world-class climber in his 40s. He was telling me about a recent trip he took to a beautiful limestone cliff in Buoux, France -- the cliff was riddled with finger pockets, perfect for hard climbing. Mike commented that he couldn't do a lot of the routes there anymore. This struck me as odd, since Mike appeared to be stronger than ever. "It wasn't that I wasn't strong enough," Mike said, "but I just couldn't get as many fingers into those little pockets as I could years ago." He complained that the pain and inflammation in his finger joints made it difficult to withstand some rock holds. I looked at Mike's hands, with knuckles thick as sausages from overuse, and wondered whether or not my mitts would be out of commission due to arthritic and painful joints by the time I turned 50.

It's almost a done deal anyway. According to the Arthritis Foundation, by age 60 most people will have some degree of osteoarthritis, a painful condition caused by the destruction of the cartilage around a particular joint (as distinguished from rheumatoid arthritis, a disease with wholly different causes). To make matters worse, we won't see it coming: More than half of the people with osteoarthritis don't notice any symptoms until after the damage is done.

Whether you're an extreme athlete or a moderate sports enthusiast, you're wise to wonder if all this exercise is going to wear you out. Your joints take a lot of pressure, and that pressure and motion wear away the cartilage. Eventually, the cartilage can rub away, leaving bone to scrape painfully against bone. Your body attempts to replace the cartilage, but the replacement surface is not as resistant to wear and tear as the original. The result can be acute pain and stiffness in the joints for which there are few effective medical remedies.

Game over?

Since I've just turned 30, does this mean I have to slow down to protect myself from a painful old age?

The issue is "largely unresolved," according to Dr. Timothy McAlindon, M.D., associate professor at the Arthritis Center at the Boston University School of Medicine. Indeed, there is evidence on both sides. One 1997 French study, for example, looked at athletes in certain sports (soccer, rugby, racket sports, and other track-and-field sports) and concluded that "joint overuse, even without notable trauma, is likely the main mechanism of osteoarthritis."

Many studies, however, have shown no connection between athletic overuse of joints and osteoarthritis. "You can use [a joint] all you want; it isn't going to wear out," says Jack Klippel, M.D., medical director for the Arthritis Foundation. The four risk factors for osteoarthritis are age, weight, traumatic injury, and genetics, according to Dr. Klippel. Overuse just isn't a big issue, he says, explaining that high levels of participation in a particular sport lead to bigger muscles, which actually protect the joints.

Rebecca Kern Steiner, a certified specialist in orthopedics, concurs with Klippel and explains that "what often leads to osteoarthritis is not overuse, but faulty mechanics (e.g., a joint that moves too much, doesn't move enough, or is improperly aligned)." Faulty joint mechanics generate abnormal shearing and compressive forces on the joint. If not corrected, she warns, joint degeneration will result.

However, the fact that a traumatic injury incurred as a result of overusing the joint can lead to osteoarthritis suggests that the debate may boil down to semantics. After all, if what causes the "traumatic injury" is actually an unhealed tear in the cartilage that's gone unnoticed and is then never allowed to heal, what's the difference between overuse and acute injury? Dr. McAlindon agrees and explains that what defines an injury or "traumatic event" could be a microscopic tear or a cumulative build-up that goes unnoticed by the individual, making it impossible to differentiate the effects of repetitive activities versus those of trauma.

The same logic applies to faulty mechanics. An individual could overuse a joint for years before realizing he or she has poor joint mechanics. This is because most of us have a muscle imbalance or faulty alignment in some of our joints, and this faulty alignment isn't necessarily painful, even when it is causing joint degeneration.

What level of exercise is safe?

If you are as fanatical about your favorite form of exercise as I am about rock climbing, then you do it way too much -- to the exclusion of much more important things, some would have you believe. So, assuming that this level of joint overuse could possibly lead to osteoarthritis, how much is too much?

This is still an open question, but according to Dr. McAlindon, most recreational activities, practiced 2-3 times a week, are completely safe for a healthy, non-overweight person who hasn't suffered a traumatic injury. If you are looking for a good form of exercise but are worried about your weight or an injury, he suggests a low-impact activity, like swimming.

If "taking it easy" is definitely not an option, then you could find a physical therapist who is a certified specialist in orthopedics. Your specialist can identify faulty joint mechanics or a muscle imbalance and prescribe a course of treatment to correct the underlying problem. Often the underlying reason for joint pain or degeneration is a problem with a completely different part of the body that directly impacts the joint in question. Evidence suggests that a treatment program prescribed by a physical therapist can actually lead to cartilage reconditioning and joint regeneration, thus reversing the degenerative changes that lead to osteoarthritis.

Voodoo remedies?

Fast-forward 20 or 30 years: You're now 65, and you have osteoarthritis in your fingers and knees. You can probably chalk it up to that joint pain you never let heal back in your 40s. The solutions for the pain range from FDA-approved pills to a concoction from your mom's kitchen pantry. In my family, the home-spun remedy involved soaking a bunch of raisins overnight in rum. What you do with them after that, I'm still not sure.

Aside from bucolic solutions, nonsteroidal anti-inflammatory drugs (NSAIDs) are the most commonly used treatment agents, but they frequently have adverse side effects such as stomach upset and ulcers. A new set of pain relievers called COX-2 inhibitors boast good results without the side effects of NSAIDS.

Among commonly used treatments for osteoarthritis are glucosamine and chondroitin supplements. The Journal of the American Medical Association recently published an analysis of 15 different clinical trials performed to determine the efficacy of glucosamine and chondroitin on osteoarthritis in the knee and hip joints. The analysis concluded that glucosamine and chondroitin probably do provide a benefit to patients, and due to their safety could have considerable utility in osteoarthritis treatment. However, there is no evidence that glucosamine or chondroitin can prevent osteoarthritis; all of the clinical trials performed have been on patients who already have osteoarthritis. "It would take many years and studies on many thousands of people to provide evidence that glucosamine or chondroitin actually prevents osteoarthritis," says Dr. Klippel.

On with it

Always eager to help out in the name of science, I'm ready to go to Buoux, France, to climb. Despite my sore fingers, I need to establish a baseline condition -- right? Upon my return to the United States, I will begin a program designed to curb the onset of osteoarthritis in my fingers. I will rest more at the end of a climbing day to prevent any traumatic injury -- noticeable or unnoticeable -- and I will ice my fingers and joints to prevent inflammation. If I'm out on the road, I will even dunk my fingers in the nearest ice-cold stream to cool them down after a day of climbing.

I'm also headed to a knowledgeable physical therapist who can identify any muscle imbalances or faulty joint mechanics in my body, and I will try to correct them now. Naturally, I will be forced to return to the south of France every year in order to adequately monitor the progress of my preventive regimen. I know it sounds tough, but I'm willing to sacrifice for the advancement of science and for the good of mankind.

Related links:

Rx.magazine feature stories: Nature's Cure for Osteoarthritis, Already Celebrexing?

Outside link: The Arthritis Foundation

Outside link: Boston University is conducting a 12-week online study of glucosamine for knee osteoarthritis. If you are over 45 and would like to learn more about this clinical trial, visit their website.