Is running bad for your joints?

Did anyone watch the Biggest Loser marathon Tuesday night? The doctor pulled a few hurting contestants toward the end to avoid further “injuring joints.”  That was obviously the right thing to do (I was wincing for them!) but it also fuels the general consensus that running a marathon can damage your joints.  I’ve been told this by well-meaning family and friends, but is there any truth in it? Here are two articles that have helped me form a response.

The NY Times posted an article in 2009 called, “Physical Ed: Can Running Actually Help Your Knees?”   It discussed one study that followed marathon runners before and after a marathon, and scanned their knees again ten years later. Here’s what they found:

“The results were striking. “No major new internal damage in the knee joints of marathon runners was found after a 10-year interval,” the researchers reported. Only one of the participants had a knee that was truly a mess, and he’d quit running before the marathon …. His exam prompted the researchers to wonder whether he would have been better off persisting as a runner, because, as they speculate, “continuous exercise is protective, rather than destructive” to knees. [Emphasis mine.]

In order to avoid injuries, the author wrote:

“…one of the best deterrents against a first (or subsequent) knee injury is targeted strength training. “The hip stabilizers, quads, hamstrings and core must all be strong enough. As soon as there is weakness, some other muscle or joint must take over, and that’s when injuries happen.”  You can read the full story here.

Another article, titled “Can you wear out your joints?” writes:

Clearly, running stresses the weight-bearing joints. In fact, up to 5 to 7 times your weight is supported by your knees while jogging. Although the research is mixed, long-term runners are not clearly more likely to wear out their weight-bearing joints than people who are sedentary.

For example, a large study of runners published in 1998 found that over a nine-year period, members of a running club ages 50 and older had no higher incidence of OA than an otherwise similar group of non-runners. A more recent study came to a similar conclusion. Runners averaging 3.5 miles of roadwork each day had 25% less musculoskeletal pain than those averaging just 2 miles each week.” [Emphasis mine.]

Here’s the summary:  Yes, running is a high-impact sport in which the body takes a lot of pounding.  However, running does not appear to damage joints.  In fact, it can actually be beneficial to your bone health and joints IF you’re smart about your training, incorporate weight training, and allow your body to adapt to each new level of stress.

Back to the Biggest Loser Marathon…I believe a marathon can be done pain-free, when the appropriate training is completed. But is five months enough time to prep a sedentary body for that kind of stress?  My personal conclusion is that the contestants have trained too quickly for the marathon and are battling over-use injuries, (which, by the way, can occur in any sport.)

Do you run into this assumption? How do you respond? What are your thoughts on the BL marathon?