Fit to Practice: Running won't ruin your knees

At least once a month someone points out to me that all the swimming, biking, lifting, and running I do is somehow bad for me. Typically this person relates a story about how he or she used to be physically active at some point in his or her life-usually during high school-got injured, and now experiences pain when they try to swim, bike, lift, or run. “If you keep doing what you're doing,” he or she usually says, “you'll wind up just like me.” I typically laugh it off, remark that I'm doing OK so far, and ask the person if they've seen any of the long-term research on the subject. That last bit is usually the conversation killer. And that's a shame because the research clearly proves that running isn't bad for your knees.

Many studies demonstrate that running is actually good for your knees. That's a challenging concept for many people to accept. The reality is that many out-of-shape and overweight people have experiences that tell them otherwise. When they try to run, it hurts. Hurting means bad things are occurring in the body. Their knee pain must be related to all those sports they played in high school, not the extra 40 pounds they've accumulated since graduation. This fear of knee pain is enough to stop many people in their recliners. Making matters worse, people often take up running as a means to lose weight. Added weight equals added force acting on weakened knees and support structures equals pain and potential injury. As a coach, I never push pounding the pavement to someone that needs to lose 30, 40, or 50 pounds. It's a recipe for injury, agony, and abandonment. Instead, I advise swimming or biking, walking on soft surfaces, and focusing on diet until we can build strength and stamina and drop some weight. But I'll ultimately encourage them to lace up their running shoes.

In the June 2010 edition of the Official Journal of the American College of Sports Medicine, researchers evaluated this question: “What Is the Effect of Physical Activity on the Knee Joint? A Systematic Review.” This meta-study evaluated all pertinent publications on the subject through November 2008. Their conclusion: “these findings indicate that physical activity is beneficial, rather than detrimental, to joint health.” Pretty straightforward. But there's more. In 2008, Skeletal Radiology published an Austrian study that performed MRIs on seven runners before the Vienna marathon in 1997. Everyone's knees looked good and healthy. Ten years later they repeated the MRI studies on the marathoners. Of the seven, six had maintained their running schedule; one had become sedentary. Surely all that running had to ruin their knees? Nope. The six runners demonstrated no evidence of knee damage or changes during the 10-year span. The runner who had stopped doing marathons showed “severe deterioration in the intra-articular structures of his knee.” Guess that couch is pretty risky to the knees.

Perhaps the most famous ongoing study on runners vs. non-runners is from Stanford University. Since 1984, 45 runners and 53 non-runners have had their knees radiographed regularly and evaluated by orthopedists and radiologists for signs of damage. The latest findings were published in 2008 in the American Journal of Preventive Medicine and found that after 18 years, 20 percent of the runners had developed radiographic signs of osteoarthritis (OA) while nearly a third, 32-percent, of non-runners had OA. But maybe these studies are biased because they selected people who identified themselves as regular runners. Maybe they were blessed with better genes or stronger knees than the rest of us. Well, that's been researched, too. The famous Framingham Heart Study examined data from 1,279 participants over a nine-year period. In their published findings in a 2007 journal of Arthritis & Research, they found no association between exercise, including running, and knee OA.

All the current research concludes that merely running does not cause or accelerate knee OA. High-impact sports such as basketball, football, and hockey have all been found to lead to higher incidence of knee OA. So does weight gain. Every pound of excess weight adds about four pounds of stress on the knee. That 20 pounds you picked up since high school means your knees are subjected to an additional 80 pounds of stress with each step. Those extra twenty pounds also double your risk of developing knee OA. Further, that spare tire is likely to cause a knee injury when you round second base a touch too fast during the annual church picnic softball game. And let's not forget the damage all those inflammatory chemicals pumped out by fat tissue are causing to every joint in your body. To avoid knee OA, avoid hockey, ice cream, and sugary drinks. Sounds like a plan.

So the next time someone throws up the old “bad for your knees” excuse for not running, you'll be able to give the same answer I do. If you'd like to start running but maybe aren't up to it yet, try these tips:

• Walk. Start by walking briskly at between a 20- to 18-minute per mile pace until you lose enough weight to safely (and pain-free) run. This is especially important if you're more than 20 pounds overweight. Extra weight can cause inflammation, the precursor to OA.

• Previous injury? Go slow. If you've had knee surgery, don't set out to run six-minute miles or a marathon. Try taking it easy, an eight- to 10-minute mile pace for 30 to 40 minutes each day.

• Stretch later. Studies show that stretching before running can actually impair performance and may contribute to more injuries. Instead, stretch after you're done walking or running.

• Get equipped. If you're new to running, visit a reputable running store and have your stride analyzed and proper shoe recommendations. While minimal and barefoot shoes are all the rage, they may not be the best for a new, unfit, or heavy runner. Good socks, shorts, and a shirt can make even the hottest or coldest days tolerable.

• Strength train. Regardless of your objectives, it's vital that everyone, especially those over age 30, engage in some form of strength training every few days. You'll help slow down natural age-related muscle loss, toughen support structures, and increase flexibility-all very good things.