Knee pain is so common among runners that the injury, officially called patellofemoral pain syndrome, is often referred to as “runner’s knee.” This pain starts when your knee cap isn’t tracking smoothly as you bend and straighten the knee joint.
You feel the pain on the front of the knee, underneath the knee cap or around the edges. It’s usually worse when you’re running, going up stairs, or after prolonged sitting with your knees bent, such as during a long drive.
Numerous factors can cause runner’s knee, and getting rid of it for good involves strengthening and balancing all the muscles in the chain from hip to ankle. Many, however, can find initial relief from a few tactics to get the knee cap tracking more smoothly and reduce forces on the knee while running.
1) Stretch Your Quads
One of the first things to try is stretching the front of your leg. “Quadriceps flexibility should be primary,” says Phil Wharton, musculoskeletal therapist and mobility expert. The quadriceps straighten the knee joint, pulling directly over the knee cap. Stretching this muscle group releases pressure on the knee cap and often allows it to track better.
To stretch the quadriceps, first lie on your side in a fetal position with your knees pulled up and your hips stacked squarely on top of each other. Reach down with your lower arm and grab the bottom of your foot or hold onto your shin to keep that leg from moving. With your top hand, grab the front of your top ankle and rotate that leg down and back by contracting the muscles in your butt and the back of your leg. Take care to stay in the same plane—don’t let your knee drift up and open your hips. Pulling your lower leg tight to your butt focuses the stretch on the quad above your knee; pulling backwards so the knee moves behind your torso stretches the upper quad and hip flexor. Move to your natural end range of motion, then bring the leg back into a relaxed position stacked on top of the other. Repeat 8 to 10 times on each side. Since this movement is working on release and range of motion (not a static stretch to lengthen the muscle), you can do it before or after running.
2) Strengthen Your Quads
As a second step, Wharton recommends doing seated knee extensions as a simple, gentle, and effective method to improve knee tracking and stability. Studies have shown that strengthening the muscles around your knee can reduce pain. Start by sitting on a chair or bench with your feet flat on the ground. Lift one foot until the leg is straight and locked in front of you. The muscles above your knee on the top of your thigh will be contracted; squeeze them as tight as you can and hold for 5 to 8 seconds, breathing deeply. Relax and drop your leg. Repeat 8 to 10 times on each side. You can increase the resistance by adding ankle weights. This exercise can be done anywhere at any time and often provides immediate relief by aligning your knee cap in addition to strengthening the muscles to prevent further injury and pain.
3) Lower Your Heel
Choosing a shoe with a lower heel height can reduce the forces on your knee and often relieve pain. Running shoes are built with different levels of heel-to-toe drop, or the difference in height between the heel and the forefoot. Those who espoused minimalism claimed that a lower heel drop was more natural and inherently better. Simon Bartold, podiatrist, biomechanical researcher and consultant with Solomon, argues, however, “There’s no such thing as good or bad drop, it is how you use it.”
A shoe’s drop changes your center of mass over the shoe. “If you have a higher drop shoe, it is going to shift your center of mass forward, and if you have a lower drop shoe it’s going to shift your center of mass backwards,” Bartold explains. That backwards shift reduces the rotation going through the knee joint, and thus reduces the load on the knee. Bartold points out, however, “You have to put the load somewhere else. You can reduce the load at the knee, but you will increase it at the ankle joint.”
Understanding this allows you to move the stress around to spare areas where you are weak. “If you’ve got somebody who has chronic anterior knee pain, it would be completely sensible to put them in a lower drop shoe, or even get them to do some barefoot training, providing you monitor what is going on at the ankle,” Bartold says. Whatever change you make is going to stress your body in a new way, so make gradual adjustments to avoid replacing one injury for another. You might at first choose a shoe with an 8mm drop rather than 12mm, or, you could only run a few miles a week in a low-to-zero-drop shoe to start. As you adapt to your new shoes, your stride may subtly change as well, which may further reduce knee stress.
4) Take Quicker Steps
Another way to manipulate forces is to play with your cadence, or how many steps you take each minute. While your body naturally chooses a cadence that is most economical for your stride, studies have shown that increasing your step rate can substantially reduce the load on your hips and knees.
Don’t get caught up in the idea that there is a perfect cadence for everyone, often cited at 180 steps per minute. “That’s something that I argue against vehemently,” says Bryan Heiderscheit, a leading researcher on cadence at the University of Wisconsin. “The idea that there is single optimum for all flies in the face of the science.” Your best cadence will depend on your speed, flexibility, strength and stride mechanics, and most of the time you can trust your body to optimize it.
It’s when you have a problem, like knee pain, that Heiderscheit recommends playing with your cadence. “Whatever your turnover is, measure it at a particular speed, then go for trial a run with an increase of 5 to 8 percent, and see if it changes your symptoms,” he says. “If it does, great, use that strategy for a period of time to get those symptoms under control.” The new pattern will require more effort, so it doesn’t have to be permanent, although you may find the new turnover becomes your new default.
You can actually count how many steps you take per minute, but far easier is to monitor your cadence using a smart watch or fitness tracker. Most of the time you can increase turnover just by focusing on stepping faster. Many find it easier to focus on swinging their arms quicker, and their legs follow the rhythm.
Heiderscheit warns that some people who just try to step faster end up with a “really wonky form.” Increasing cadence works best if you also work on moving your stride from reaching in front of you to pushing behind you. “If you’re going to increase your step rate, also try to land with your foot closer under your hips,” Heiderscheit recommends.