Why Running May Actually Be Good For Your Knees

If you're a runner, you've likely heard it, and if you're not a runner, you may have said it: running is terrible for your knees. Not so fast: a growing body of research is suggesting that running may not only be fine for your knee health, but actually improve it.

This Myth Kneeds Science

Despite how surprising this fact may be to most people, it's nothing new for scientists. As far back as the 1980s, studies were showing that running wasn't associated with knee arthritis, nor with other types of degenerative joint disease. Still, researchers weren't sure why this was the case. It was possible that there was something else at play: runners tend to have lower body weight, for example, which is known to reduce the risk of developing knee problems. But other researchers have suspected that running really did play a role.

For a study published in 2016 in the European Journal of Applied Physiology, researchers had male and female runners either run on a treadmill for 30 minutes or spend the same amount of time sitting quietly. Each participant then did the opposite activity on a subsequent day. Before and after each session, the researchers drew blood from an arm and synovial fluid—the substance that lubricates your joints—from a knee. Then they analyzed it for a number of elements, including the cells associated with knee inflammation and a substance called cartilage oligomeric matrix protein, or COMP, which is often used as a marker of arthritis. The results were quite dramatic: after running, the participants' knees had lower levels of the cells linked to inflammation. In addition, the COMP levels in their knees had dropped while the levels in their blood had risen, as if running had helped their knees dump some of the arthritis-associated substance. After sitting, however, those inflammatory cells increased and the knee's COMP levels rose. According to the New York Times, study author Robert Hyldahl concludes that moderate running is "not likely to harm healthy knees and probably offer protection."

Then Why Do My Knees Hurt?

It's fairly common for runners, especially new runners, to experience knee pain. But that pain rarely comes from a breakdown of their joints, and often has some easy fixes. For example, a study of women with patellofemoral pain syndrome—commonly known as "runner's knee"—showed that an eight-week strengthening program that focused on the hips, core, and lateral leg muscles was able to reduce their pain and increase their running ability. (The Myrtl routine is a particular favorite of this editor.) Along with muscle weakness, other culprits behind knee pain are often old shoes or running too much mileage too soon. Of course, if you have nagging pain that doesn't go away, the best advice is to see a doctor. But in the end, don't let the fear of knee damage scare you away from running. It could actually keep your knees healthy.

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Written by Ashley Hamer May 10, 2017