Here’s Why Your Knees Hurt After Running
What is runner’s knee?
Runner’s knee—or, in more scientific terms, chondromalacia patella—can occur when the cartilage under the kneecap is damaged. It’s one of the most common injuries runners face due to that cartilage being a natural shock absorber.
According to Becs Gentry, a Peloton Tread instructor, and Nike Run ambassador, there are a few different reasons those symptoms—aka kneecap pain, swelling, or feelings of popping or grinding—ever even surface in the first place.
But runner’s knee is also a “catchall” term for any knee pain runner’s may be experiencing, and it doesn’t necessarily have to do with damaged cartilage, says doctor of physical therapy Kelly Starrett, an author, professional athlete coach, mobility expert, and founder of The Ready State. Instead, Starrett says to think about knee pain as your body’s way of signaling a “request for change” in some aspect of your training, mobility, and readiness.
What causes runner’s knee?
Unfortunately, it may be hard to pin down the exact cause, because knee pain is a signal that your body’s overall readiness for running is out of whack.
“There’s a lot of reasons why suddenly your brain is getting you to pay attention to your knee,” Starrett says. “You could have done tons of volume and then sat, you could have been super stressed in your life and job and family. You could be undernourished and your tissue quality doesn’t allow you to be robust and handle the volume you didn’t warm up. There’s just so many things that can go on here.”
All of those factors can cause a lack of mobility in your hip flexors, tight muscles and tendons, sensitive muscle tissue, and congestion in the connectivity between your muscles. Those physical symptoms can cause pain all the way down to your knee—especially in runners that tend to have tight quads, which are connected to the knee (along with the calves and hamstrings). When you’re experiencing tightness and a limited range of motion, your body sends a signal to your brain that your knee might be in danger, which we interpret as pain.
“Areas of that muscular system can absolutely refer pain down to the knee,” Starrett says.
Other common causes of knee pain while running
Other common knee-pain-causing issues Gentry sees come from eating a poor diet that builds up toxins and can contribute to inflammation, wearing shoes that don’t provide enough support, and not having enough recovery time. “It’s important to allow the body to rest, adapt, and recover prior to the next run,” she says. “Massage and Epsom salt baths are something I always suggest when runners have muscular soreness, as they can both help reduce the recovery time and soothe the body.”
As far as footwear goes, make sure that you’re wearing a shoe that was created for your foot type in addition to replacing your shoes about every six months (or sooner depending on how much mileage you do).
You’re going too hard, too soon
As exciting as it can be to start a new training program or modality, you should always scale back to begin with in order to give your body time to get acclimated to your training. “You might experience runner’s knee from increasing your mileage too soon, since going from zero miles to countless miles in a short time span can cause pain and aggravation to the body,” says Gentry.
To circumvent this, start off modest. And if you aren’t sure what that looks like, consider enlisting the help of a professional run coach or using an app that has running plans such as the Nike Run Club app.
Your technique needs improvement
Another reason you may be experiencing knee pain while running is poor technique, says Gentry. It happens to the best of us, especially as we fatigue, but it’s definitely something you should be actively thinking about on your runs.
Make sure that your hips aren’t shifted backward, your head is in a neutral position, your shoulders are relaxed, your chest is open, and that you’re swinging your arms forward and backward. You’ll also want to avoid butt-kicking as this can cause unnecessary stress on muscle groups like your hamstrings, which as a result can pull on other muscles and aggravate your knees. Additionally, you should try to strike the ground with your mid-foot, and making sure that you’re not running with your knees locked out.
4 ways to prevent running from hurting your knees
While getting rid of the pain is great, there are also some ways to prevent your knees from hurting in the first place. Starrett describes this as “changing the inputs so that the local tissue physiology is improved and the brain recognizes that these positions are safe.”
1. Practice Isometric exercises
“The first order of businesses that try to see if we can signal to the, the brain that these positions of the knee in movement are safe,” Starrett says. “The easiest way to do that is to get someone to do some isometrics, which are muscle contractions without movement.” The idea is that if you mimic the movements of running for an extended period of time, your brain will learn that those are “safe” positions to be in, and so pain signals won’t fire in the future. It will also help you attain your full range of motion, which should help with knee pain.
“It gets us very comfortable in those positions, ends up restoring our native range,” Starrett says.
Starrett recommends knee pain moves like doing lunges, and eventually progressing to raised leg lunges, while breathing deep, flexing your glutes, and holding the position.
“Get yourself into a big lunge position with the feet pointed straight, both feet pointed straight ahead, all the toes on the ground,” Starrett says. “You’re gonna lower yourself down until you feel a pull in your back leg. But more importantly, until you can still squeeze your glute on the back leg. Hold that for five to 10 big breaths, because if you can’t breathe in a position, you don’t own that position. And running is about moving from position to position while breathing hard.”
2. Practice soft tissue mobilization (foam rolling)
Tightness in your soft tissue could be causing pain in your knees, so you’ll want to foam roll (especially on your quads), focusing on areas where you feel pain when they’re compressed by the foam roller or pressure point ball.
“Restricted tissue may be causing tension,” Starrett says. “It may be changing your gait, it may be causing your brain to perceive something that’s going on in the knee. It doesn’t matter what the mechanism is. If I have you lay on a roller on your quads, it should just feel like pressure. It shouldn’t feel like you’re being water boarded.”
3. Train with a running coach
People think running is one of those things you just go out and do, but learning how to run correctly from the get-go can help keep your knees healthy for years to come. “If you’re unsure about correct running technique, find a coach who can help you analyze your running style and work with you to make it stronger,” Gentry says.
4. Invest in a good pair of running shoes and socks
You wouldn’t show up to swim practice without a quality bathing suit, right? Well, the same goes for running: You need trustworthy gear to get the job done. “The technology in sneakers today is very advanced, and most running shoes are designed to assist the human body, so it’s a great idea to head to a running store for a gait analysis,” says Gentry. “In most cases, they’ll be able to show you shoes that suit your natural running style. Definitely remember to wear shoes that are comfortable, though.”
5. Keep a training diary
To make sure you’re not overdoing things—especially at the beginning of your running journey—take the time to keep track of your sessions. “Starting a training diary will help you clearly see and outline which days you dedicate to running, training, and to recovery,” Gentry says. “This way, you’ll be able to balance yourself out and not do too much, too soon.”
6. Build your muscle strength
Adding some strength training into the mix as well can do wonders for protecting your body—and turning you into a better runner. “Building your muscular strength is so important. Around every joint, there are muscles, tendons, and ligaments. Runners need to ensure that their whole body is looked after and strengthened for running, given the impact it has on the body,” Gentry says. “Using bodyweight or weighted exercises and focusing on single-leg strength—as well as double-leg strength—will help build your power and hopefully keep knee injuries at bay.”
We know running with knee pain isn’t ideal, but if you make sure you’re wearing the right gear, you’re focusing on your form and getting in cross-training sessions (strength training is your BFF), recovering, and eating foods to fuel you, it should be gone in no time! And never underestimate the power of ice cup massages and Epsom salt baths.
Is it ok to keep running with runner’s knee?
Try practicing the techniques above, with an emphasis on isometric exercises and soft tissue mobilization. If that doesn’t relieve the pain, you should see a doctor.
Does runner’s knee go away?
If you allow yourself to recover properly from the exertion of running, and you practice isometric exercises and soft tissue mobilization, runner’s knee should go away. If it doesn’t, you should consult with your physician.