The Pso-What?!?! The Psoas Muscle and Why It Matters

What is a Psoas?

The Psoas (pronounced: So-as) is a muscle that attaches to our lower spine (transverse processes of the lumbar vertebrae), stretches down into our pelvis and inserts into the inner top portion of our thigh (lesser trochanter of the femur).  It is one of our most deep, most core muscles in our body.

The Psoas joins the Iliacus to form the Illiopsaos muscle group. It is the biggest and strongest player and together they work with what is most commonly called the hip flexor muscle group. Together they contract to pull the thigh in towards the torso.

The Psoas is the only muscle that connects the top of our structure to the bottom half, our legs to our body, the inside to the outside, and the back to the front body.

This muscle group is one piece of an interwoven network of muscles that make up our core. Joining the Psoas are the Transverse Abdominals, Multifidus, Diaphragm, Pelvic floor muscles, and Quadratus Lumborum.

Why should I care?

The Psoas enables us to walk and run and for long distances. Every time we lift our knee, the Psoas contracts. When our leg swings back, the Psoas lengthens.

This muscle group often remains in a contracted shortened state due to sitting for long periods of time. Even after standing and walking around, our pelvis tilts forward (anteriorly), pulls on and shortens the lumbar vertebrae. This action is a major contributing factor to low back tension, SI joint pain, and compression of the lumbar discs.

As the tight Psoas tilts the pelvis forward, it also creates an arch in the low back (lumbar lordosis) and pooches out the belly. By essentially being pulled down by tight hip flexors, it makes it harder to stand up straight with your shoulders back and your head up looking toward the horizon.

Muscle memory maintains this shortened state, even when you head out for a run.

A hypertonic (read: tight) and inflamed Psoas can lead to irritation and entrapment of the Iliolinguinal and the Iliohypogastric nerves, resulting in either numbness, a sensation of heat or water running down the front of the thigh.


A weak and overstretched psoas can create instability by jutting the pelvis in front of the chest, neck and head. This limits space between the vertebrae in the low back, rounding upper back and collapsing the shoulders forward.

The psoas is considered the muscle of the soul. We often hold great amounts of stress, worry and fear in this muscle. When we are hurt emotionally, there is an instinct to curl up into a fetal position. Our psoas contracts and shortens as a form of protection from what pains us.

How do I stretch my Psoas?

Lengthening your Psoas can be approached in a few different ways. Opening up his area of your body will help you stand taller and release tension presenting throughout the back, neck and shoulders.

Runner’s Lunge: (See header picture above)
(1) Put right foot forward (with your knee behind your foot) and the left knee and lower leg on the ground. (2) With your pelvis tucked, shift weight forward, easing into the stretch. (3) If your psoas feels tight, your tendency may be to arch your low back; make it a point to keep the back straight.



(1) Step forward with your right foot in front of you. Lunge forward until your knee is at a right angle. The left foot can either be on the ball of the foot or with the heel planted. (2) As you face forward, raise your arms overhead as you stretch the front body and open up the front of the leg (hip flexors) and torso (Psoas and Abdominals). (3) Shift your weight and right arm up towards the ceiling and reach back, opening up the side body, lats and armpit. Look ahead or for a deeper stretch, look toward the ceiling.



(1) Kneel on the floor with your knees hip width apart and thighs perpendicular to the floor. Press your feet and lower legs into the floor. As you begin to shift your weight back, try not to clench your bottom. (2) Lean back as you rest your hands behind you where your back meets your pelvis. The base of your palms on the top of the hip & butt with fingers pointing down. Open up the chest, draw the shoulder blades back and down onto the back and let the heart shine through. (3) Twist to the right and place your hand on the right heel or foot then shift towards the center and lean to the left and place your other hand on the left heel or foot.* (4) Press your thighs back to 90 degrees and lift your ribs and pelvis up, creating space throughout the front body.
*If you’re not able to comfortable touch your feet without compressing your lumbar vertebrae, turn your toes under and use your heels as the point of stability.

How do I strengthen my psoas?

Strengthening the psoas is NOT necessary to stabilize the pelvis and the lumbar spine. More often than not, the psoas is already tight and shortened and does not need anymore tension added to it.

42219897_sWhen it comes to our muscles, the psoas is one of our heaviest hitters. It is the deepest, strongest most core of our muscles.

They stabilize us, hold us up right, and move us through our day without thinking twice about its function… until they are tight, shortened and inflamed. Then our world comes to a screeching halt as we succumb to our back or pelvic pain.

Taking care of our most core muscles is essential for the most functional movement. With a strong healthy psoas the rest of the body can function and balance.

For personalized guidance on how to release the psoas, click HERE to submit a request for treatment.


Gudmestad, Julie. Yoga International. “How to Stretch and Strengthen the Psoas”. June 7, 2013.
Hugins, Jill. Runner’s World. “Runners Guide to the Psoas”. August 31, 2011.
Koch, Liz. The Psoas Book. Felton, CA.: Guinea Pig Publications, 1997. Print.
Koch, Liz. Core Awareness. “The One Muscle the Does Not Need Strengthening”. August 2005.
Myers, Tom. Anatomy Trains. “Cobra“. January 20, 2013

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