Is running bad for your knees?

Running gets a bad rap when it comes to joint health, especially the knees. You’ve probably heard someone say, “I used to run, but it destroyed my knees,” or, “Running causes arthritis.” But when you look at the actual research, that’s not the full story, far from it actually.

Yes, running is one of the most injury-prone sports. But most of those injuries don’t come from the act of running itself, they come from how people approach it.

There are two main reasons runners get hurt. First, a lot of people fall in love with running and take it too far. Running every day, never taking rest days, pushing volume too fast, chasing weekly mileage totals like it’s a badge of honor and pushing through nagging injuries will lead to problems. Too much of a good thing can be a bad thing, especially when you do not listen to the signs that your body needs some rest. 

The second reason is that most runners don’t touch weights. They avoid strength training and don’t build the muscle support and joint control needed to handle the demands of repetitive impact. When you only run and ignore strength work, you leave your body vulnerable - especially at the knees, hips, and lower legs. 

What’s rarely talked about is how much strength training can protect runners. Study after study shows that adding resistance training not only improves running performance but that it reduces injuries significantly.

Just two strength sessions per week can improve your running economy by up to 8% and cut your risk of injury in half or more! 

Stronger glutes, hamstrings, calves, and core muscles help your body absorb impact, maintain better form, and avoid the overuse breakdown that sidelines so many people.

Now let’s talk about the big myth: running ruins your knees.

Your joints are living tissue. Cartilage doesn’t have a direct blood supply like muscle does. It gets nutrients through diffusion, which is aided by movement and compression. The more you move your joints, the more blood flow increases around them, the more synovial fluid circulates, and the more your joints stay lubricated and “fed.”

Like a well-greased machine, the parts move better when they’re used regularly and properly. When you stop moving, everything tightens, weakens, and wears down faster. Your body is meant to move and it functions best when you are in motion.

Recreational runners are actually less likely to develop knee osteoarthritis compared to people who are sedentary. That’s been shown in multiple long-term studies. On MRI, the small changes that happen to knee cartilage after a run go back to normal within a couple of hours. So that wear and tear people talk about is not a permanent change in your knees, just like your elevated blood pressure while lifting weights is not permanent.

There’s no sign of long-term damage, unless you’re training at extreme volumes over many years. In moderation, running actually seems to protect the joints.

And I've even seen many people who put absolutely absurd amounts of miles on their feet have longevity in running due to strength training, proper rest, and nutrition. So in reality, if you take care of your body, get out there and run as far much as you want, just support your body with proper strength and care.

The truth is that sitting on the couch and doing nothing is far worse for your knees than going for a few runs a week. Motion is medicine, and strength is protection. Runners who respect their bodies, build their strength, and train smart are not breaking down...they’re building up.

If you want to stay healthy and keep progressing in your running, stop avoiding the gym.

You don’t need to be a powerlifter, but you do need to train your body to handle the stress you’re putting on it. That’s how you keep running strong!

Stay Healthy,

Thomas Stevens

Strength guide for runners: Click Here!