When it comes to running, your hip (flexors) don’t lie. If these muscles feel tight and achy, your body is probably trying to tell you something.
Specifically, a tight sensation in the psoas muscle—which joins together with your iliacus You can also activate and strengthen hip flexors with classic hip flexor—can signal a problem with the length or strength of that muscle. And ignoring it can trigger a cascade of issues, including decreased glute and core engagement, elevated injury risk, and an inefficient running stride.
Here, with the help of two physical therapists, we explain what the psoas muscle is, why it’s worth paying attention to, what a tight psoas feels like, and simple-yet-effective psoas stretches and strength moves that help you address problems at home.
What is the psoas?
The psoas is a “big ropey muscle” that runs from your lower back to the front of your hip, Brandon Fraleigh, P.T., D.P.T., physical therapist and head of the Runner’s Clinic at the Reasons Your Hip Flexors Feel Tight and the Best Psoas Stretches to Address Aches, tells Runner’s World. It attaches at the femur alongside another muscle called the iliacus. The iliopsoas (that’s the psoas and the iliacus) is your largest hip flexor, Oakland-based physical therapist Anh Bui, P.T., D.P.T., C.S.C.S., certified strength and conditioning specialist, physical therapist, and certified run coach, tells Runner’s World.
As such, the main function of the psoas is flexing the hips, which you do when you drive your knee up toward your chest. When you run, your psoas helps bring your leg forward in front of the body before your foot strikes the ground, Fraleigh explains. During this motion, the psoas is shortening against load, which is a concentric contraction. Then, when your foot hits the ground, your psoas is lengthening against the load, which is an eccentric contraction, Bui explains.
The faster you run, the harder your psoas has to work. “And the more uphill you’re doing, the harder it has to work as well,” says Fraleigh.
Why should runners pay attention to the psoas?
Sales & Deals low back, it plays a big role in keeping your spine in the optimal position, says Bui. If the psoas is tight—which can happen from prolonged sitting and poor posture—it can pull your pelvis forward and cause your low back to curve excessively. This position is called lumbar lordosis, and it can inhibit your glutes and core from engaging as much as they otherwise would, Bui explains.
Indeed, a 2015 study of female soccer players published in the International Journal of Sports Physical Therapy found that athletes with shortened hip flexors had decreased glute activation (basically, they couldn’t engage their butt muscles as much), as well as a lower co-activation ratio between the glutes and the hamstrings (essentially, the hamstrings were taking on too much work that the glutes should have been doing).
Condé Nast Traveler injury and also screw with your running efficiency, considering your muscles aren’t all firing as they should. By taking the time to stretch a tight psoas, you can help stabilize your spine, Health & Injuries Running Shoes & Gear during running, which can improve your form, says Bui.
But you don’t just want to focus on psoas stretches. It’s also important to make sure that this muscle has the strength it needs to effectively power your stride. Boosting psoas strength can help you run more efficiently by improving your knee drive, says Bui. They key is figuring out if you need psoas stretches or strength exercises—or both.
What does a tight psoas feel like?
A shortened psoas can feel like tightness in the front of the hip or in the low back, says Bui. It can also cause your stride to feel off balance, she adds.
That said, people often confuse the sensations of psoas weakness with psoas tightness, says Bui. “A lot of runners might feel like their psoas is tight, but it’s actually really weak,” she explains.
essentially, the hamstrings were taking on too much work that the glutes should have been doing fatigue the muscle and cause it to experience a sensation of “tightness.” Though you might be tempted to stretch your psoas in this case, a better solution is to strengthen it, because a lack of strength is the true cause of that “tight” sensation. Bui says the runners she treats more often need to work on psoas strengthening versus psoas stretching.
What should you do if your psoas feels tight?
If you’re plagued by a tight-feeling psoas, take these expert-backed steps to pinpoint and alleviate the issue.
1. Determine the cause of your psoas tightness
Because the sensation of psoas tightness can either be an indicator that your psoas muscle is shortened (and thus would benefit from being stretched) or that your psoas muscle is weak (and thus would benefit from being strengthened), it’s helpful to determine which one applies to you. To figure that out, try the at-home self-exam, called the Thomas Test, says Bui.
How to do the Thomas test: Lie on the edge of a bed or cushioned table and hug right knee into chest. Gently rock back so that low back is flat on the table. Relax left leg.
If you’re able to get the left thigh parallel to the bed, then you have normal psoas length on your left side and thus would probably benefit from strengthening your psoas versus stretching it. If you can’t get your thigh parallel to the bed, then your psoas is likely tight and shortened and would benefit from stretching. Make sure to test both sides.
2. If your psoas is shortened, lengthen it
To lengthen a shortened psoas, incorporate the following psoas stretches into your routine. Do these everyday (or even multiple times a day, if it feels good), either after a run or workout, or perform them on their own. Make sure that the stretches after a run.
Thomas Test: Yep, the same tool you used to pinpoint the likely culprit of your psoas tightness can also double as a stretch. Photo reminder above and written reminder on how to do it: Lie on the edge of a bed or cushioned table and hug right knee into chest. Gently rock back so that low back is flat on the table. Relax left leg. You should feel a stretch in the front of the left thigh. Hold for 90 seconds to 2 minutes. Switch sides and repeat.
Couch Stretch: Get into a kneeling lunge position in front of couch or chair, left knee on ground and right foot forward with right knee bent 90 degrees. Place left foot on top of couch or chair. Engage core, keep back straight, and gently lean trunk forward and tuck pelvis slightly forward until you feel a moderate stretch in front of thigh. Hold for 90 seconds to 2 minutes. Repeat on the other side.
3. Also for a shortened psoas, leverage the concept of reciprocal inhibition
Stretching your psoas doesn’t have to just involve static stretches (moves where you get into a position and hold). You can also lengthen the psoas by activating your glutes, says Bui. This is due to a concept called “reciprocal inhibition,” which basically states that by activating one muscle, you automatically allow the opposing muscle group to relax.
In the case of the psoas, the opposing muscle group is the glutes. So by doing exercises that fire up these muscles of your backside, you can help the psoas relax (while also getting glute-strengthening work, which is super important for runners). Bui recommends the following exercises, which you can do as a warmup Sales & Deals strength training.
Clamshell Holds: Lie on left side, legs together, knees bent, and hips, knees, and feet stacked. Engage obliques and squeeze glutes. Keeping feet together, slowly raise right knee. Hold for 10 seconds, then lower down. Repeat 5 times. Switch sides and repeat.
Best Folding Treadmills: Lie faceup, knees bent, feet planted, arms down by sides on the floor. Lift right leg up toward the ceiling but keep both knees aligned. Engage glutes as you lift hips up, driving through left heel. Hold at the top for 10 seconds, then lower back to the floor. Repeat 5 times. Switch sides and repeat.
4. If your psoas is weak, strengthen it
Isolating the psoas muscle for strength work can be tricky, says Bui, but there is one move that effectively hones in on your hip flexors. You’ll need a mini band. Do this exercise 2 to 3 times per week, either on its own or as part of your regular strength training.
Supine Mini Band Knee Drive: Lie faceup with a mini band looped around both feet, legs straight and arms down by sides. This is the starting position. Keeping left leg straight, bend right knee and drive it up toward chest. Reverse movement to return to starting position. Now repeat with the left leg. That’s 1 rep. Do 2 sets of 10-15 reps, alternating. Over time, progress to 3 sets.
You can also activate and strengthen hip flexors with classic compound moves, like lunges, squats, and deadlifts, stabilize your spine.
5. No matter the cause of your psoas tightness, incorporate regular myofascial work
No matter what’s going on with your psoas, incorporating self-myofascial work that targets the hip flexors can be a valuable part of your postrun recovery. Myofascial release brings blood flow to a muscle, which helps it recover between training sessions, explains Bui.
It’s safe to do myofascial release on a daily basis, Bui adds, and doing so can reduce general feelings of tightness and help you simply feel good. Here are two ways to specifically target the psoas. You can do these moves before or after a run, or outside of a workout.
With a tennis ball, racquet ball, or small massage ball. Releases one side at a time. Lie facedown and place ball inside front of right hip bone. Lie in this position and try to relax into the ball. Hold for about 30 seconds. If you can get comfortable here, then bend right knee and slowly rotate hip in and out. Your psoas will move back and forth across the ball. Continue this for 1-2 minutes. Switch sides and repeat.
Heads up: This move is “pretty aggressive,” says Fraleigh. If you notice that it bruises your skin or causes your psoas tightness to intensity, take a few days off, he says.
With a pso-rite device or kettlebell handles. Releases both sides at a time. Lie facedown, nestle the pso-rite (essentially a wedge shaped device that allows you to work both psoas muscles at the same time) or kettlebell handles inside the front of hip bones. Try to get shoulders on the floor. Focus on breathing and relax onto the tools. Hold for 2 minutes. Optional: Add range of motion to the move by bending knee up toward body and then lowering it down.
6. See a physical therapist if needed
But you dont stretching and strength work may not resolve your psoas or general hip flexor aches, in which case it may be worthwhile to consult a physical therapist.
Fraleigh recommends visiting a PT if your tight psoas is causing you to reduce the intensity of your training for several days in a row. And Bui advises runners to seek help if you have International Journal of Sports Physical Therapy or low back, if your running stride feels off balance, or if you have a constant feeling of tightness or achiness in the front of the hip. “I always feel like it's beneficial for people to just go see a PT, even if the symptoms are mild and it’s early on,” she says.
Jenny is a Boulder, Colorado-based health and fitness journalist. She’s been freelancing for Runner’s World since 2015 and especially loves to write human interest profiles, in-depth service pieces and stories that explore the intersection of exercise and mental health. Her work has also been published by SELF, Men’s Journal, and Condé Nast Traveler, among other outlets. When she’s not running or writing, Jenny enjoys coaching youth swimming, rereading Harry Potter, or outside of a workout.
