Definition: The piriformis is a small, hip-stabilizing muscle deep beneath each gluteus maximus. When it’s tight, it compresses the sciatic nerve, which runs from your lower back, beneath the glutes, down the legs, and into your feet.
That tightness can cause numbness, tingling, burning, and weakness in your glutes and, in the worst cases, in the legs and toes, says Grayson Wickham, DPT, CSCS, a practicing physical therapist in New York City who has worked with athletes in the NFL, MLB, and more.
Roughly 15 percent of people have a sciatic nerve that passes through the piriformis muscle instead of underneath it. This seemingly random anatomical fluke makes you more prone to the syndrome because the muscle literally squeezes the nerve, says NYC-based physical therapist Ryan Goodell. Separately, women are six times more likely to get piriformis syndrome than men are; wider pelvic bones put more stress on the muscle in question.
Now for the factors you can control. Excessive sitting (read: having a desk job) ups your risk because it leads to tight glutes and hence, a tight piriformis. Repetitive lower-body exercise, including endurance runs and heavy lifts like squats, can have a similar effect. According to Wickham, if you skimp on mobility training, your risk of developing the condition goes up.
Piriformis syndrome can limit your performance by forcing you to lift lighter weights (because of weakness and numbness), limiting your range of motion (due to tightness), and causing strength imbalances (since other muscles will have to compensate), Wickham says.
To relax an angry piriformis and get back to your regular training plan pain-free, you need to loosen the muscle.
Wickham recommends this daily regimen, which you can perform when you wake up, before your workout—whenever. First, foam roll your glutes for 2 minutes. Better yet, use a lacrosse ball for deeper access.
Then, stretch those muscles by lying on your back, bending the knee of the affected leg, and pulling it across your torso and toward your chest as far as you can without discomfort. Once you’re in this position, flex your glute on the affected side for 10 to 20 seconds, then relax and deepen the stretch. Hold for another 10 to 20 seconds. Complete 3 to 4 reps.
While training, reduce your range of motion during lower-body moves. For example, drop less deeply into squats and lunges. Runners should take shorter strides, aiming for 180 steps per minute.
If your symptoms don’t fade after a week or two, schedule a session with a physical therapist, Wickham says. If they do, you can keep your piriformis healthy by limiting heavy leg work to two nonconsecutive days per week. Spend 10 to 15 minutes on mobility and flexibility (foam rolling and stretching) three to five days a week, he adds.
You’ll also want to strengthen your hamstrings, hip adductors, and glutes (since they all affect one another) with the below exercises, says Goodell. Perform one or two moves from each category once or twice a week.
For your hamstrings: Swiss ball leg curls or machine hamstring curls, 2 to 4 sets of 5 to 10 reps
For your hip adductors: Side plank with top leg raised and top foot resting on a bench, 2 to 3 holds lasting 10 to 30 seconds each side; split squat with band adductions or machine hip adductions, 2 to 5 sets of 8 to 15 reps, per side when applicable