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The piriformis is a small, stabilizing muscle that lies deep within your glutes and plays a critical role in running motion, helping to externally rotate your hips and keep them level, and stabilize your pelvis. It runs from the bottom of your sacrum—where the base of your spine meets your pelvis—to the top of your femur.
“The sciatic nerve passes right by the piriformis muscle, and when the piriformis contracts or spasms, it can sometimes compress the nerve, resulting in pain,” says running coach and exercise physiologist Susan Paul. This is what causes piriformis syndrome to occur.
Unfortunately for runners, logging miles consistently is a common cause of this injury. “Repetitive activities, like running, can fatigue the muscle and irritate the nerve,” Paul says.
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Identifying Piriformis Syndrome Symptoms
Piriformis syndrome can be tricky to diagnose because it can be easily confused for a herniated disc, sciatica, a proximal hamstring strain (also known as high hamstring tendinitis), or a lower back issue. Here are a few key symptoms that can help you determine whether the piriformis is the cause of your actual pain in the butt:
- It hurts to sit. Piriformis syndrome sufferers don’t always feel discomfort while running. Instead, they usually find sitting, climbing stairs, and squatting painful. (Pain while running, specifically an overstretched feeling when running uphill or very fast, is more typically a sign of a proximal hamstring strain.)
- It's tender. Piriformis syndrome often causes the area to feel tender. Applying pressure can cause discomfort or pain not only at the point of contact but also down your leg.
- The pain is centered. Piriformis syndrome is usually felt in the middle of your glutes, as opposed to something like a proximal hamstring strain that typically causes non-radiating pain centered at the bottom of your butt, where the hamstrings connect to the pelvis.
Common Causes of Piriformis Syndrome
Weak glutes are a big contributor, according to Paul. If you're constantly sitting all day, whether it be at your desk or behind the wheel, your glute and hamstring strength can decrease over time. (Some sports medicine experts call this “sleepy glute syndrome.”)
Pelvic misalignment stemming from other issues, such as a functional leg-length discrepancy or something as simple as bad sitting posture, can require the piriformis to work extra hard and tighten or go into spasm.
Any inherent weakness in the piriformis and other glute muscles can be exacerbated by sudden increases in mileage or intensity. Similarly, continuing to run high mileage with piriformis syndrome—which is possible to do—can worsen and prolong the condition.
When you run, the muscles aren’t able to fire efficiently or in sync with each other. As a result, they’re unable to withstand the repetitive strain of distance running. Failing to warm up with glute-activation exercises can make you vulnerable to this problem.
Treating Piriformis Syndrome
Simply resting is usually not enough to conquer piriformis syndrome. This is especially true if the problem ultimately lies with bad pelvic alignment. It’s okay to keep running if you can do so without pain, but avoid longer-than-usual runs (which will increase the chance of overload as you fatigue) and slanted surfaces (which will increase the risk of pelvic misalignment).
In the short term, the goal is to help the piriformis loosen and relax. If it’s impinging on the sciatic nerve, loosening the muscle should significantly lessen radiating pain. Try one of these treatments to stop a piriformis spasm.
Massage: You can see a professional massage therapist, but you can also work out tight spots on your own using a foam roller or firm ball.
Stretch: Loosening up the muscle before and after runs can help it relax and increase blood flow. Sage Roundtree, USA Triathlon-and RRCA-certified coach and yoga instructor, recommends stretches such as pigeon pose and standing figure 4, and exercises like side planks with a leg lift.
Ice and Medicate: You can apply ice and take an over-the-counter anti-inflammatory drug during acute phases, when the area is tender to the touch. But if the pain doesn't go away and lasts for more than a few days, seek professional care.
Seek Help: If the above treatments don’t bring relief, see a doctor or sports medicine professional. It could be beneficial to have your running form evaluated and to be checked for a leg-length discrepancy and muscle-strength imbalances. Orthotics may be recommended if you have excessive overpronation (inward movement of the foot when you land).
Preventing Piriformis Syndrome
To prevent recurrence of piriformis syndrome, you need to reduce the piriformis muscle’s vulnerability. One of the best ways to do so is to strength train. Making sure your glutes are strong is key to avoiding piriformis syndrome. Jordan Metzl, M.D., a sports medicine physician at the Hospital for Special Surgery in New York City and creator of Runner’s World’s IronStrength workout, recommends exercises such as jump squats, squats with weights, and plyometric lunges.
It’s also important to keep your pelvis in good alignment. Avoiding regularly running on slanted surfaces (or switching up which direction you run on the track), identifying muscle imbalances that can cause you to favor one side of your body, and sitting with good posture (your head, shoulders and hips should be aligned, your feet flat on the floor, and your weight evenly distributed on both hips) all do this.
To avoid “sleepy glute syndrome,” don’t sit for extended periods. If possible, alternate between sitting and standing when working; otherwise, take hourly breaks from sitting. If traveling on a plane, be sure to get up and walk around once every hour, and when possible, do the same when traveling by car.
And of course, you should always warm up thoroughly before a run. Dynamic exercises such as reverse lunges, single-leg hops, and single-leg reaches will wake up your glutes and help prevent piriformis syndrome.
