Thursday 9.8.11

The psoas muscle is responsible for most back pain

#1. What is the Psoas Muscle?

The number of problems caused by the psoas is quite astonishing.

The biggest factor in back and hip pain is the psoas muscle. Many believe the psoas muscle is the most important muscle in the body. The number of problems caused by the psoas is quite astonishing. These include: low back pain, sacroiliac pain, sciatica, disc problems, spondylolysis, scoliosis, hip degeneration, knee pain, menstruation pain, infertility, and digestive problems. The list can also include biomechanical problems like pelvic tilt, leg length discrepancies, kyphosis, and lumbar lordosis.

The psoas (pronounced “so – az”) primarily flexes the hip and the spinal column. At about 16 inches long on the average, it is one of the largest and thickest muscles of the body (in animals it’s known as the tenderloin). This powerful muscle runs down the lower mid spine beginning at the 12th thoracic vertebrae connecting to all the vertebral bodies, discs and transverse processes of all the lumbar vertebrae down across the pelvis to attach on the inside of the top of the leg at the lesser trochanter. The lower portion combines with fibers from the iliacus muscle, which sits inside the surface of the pelvis and sacrum, to become the Iliopsoas muscle as it curves over the pubic bone and inserts on the lesser trochanter.

#2. What is the function of the psoas?
The psoas has a number of diverse functions, making it a key factor in health. The psoas functions as a hip and thigh flexor, which makes it the major walking muscle. If the legs are stationary the action of it is a bend the spine forward; if sitting, it stabilizes and balances the trunk. The lower psoas brings the lumbar vertebrae forward and downward to create pelvic tilt.When we think of smooth, elegant and graceful movement in dancers and athletes we are looking at the psoas functioning at its optimum. It requires that the psoas maintains the pelvis in a dynamically neutral orientation that can move easily and retain structural integrity. This creates positions of the spine that require the least muscular effort.

#3. What are the common pain symptoms of the psoas? 

When the muscle becomes contracted due to injuries, poor posture, prolonged sitting, or stress, it can alter the biomechanics of the pelvis and the lumbar, thoracic and even cervical vertebrae. Typically a dysfunctional psoas is responsible for referred pain down the front of the thigh and vertically along the lower to mid spinal column. Trigger points are found above the path of the psoas on the abdomen. Frequently the quadratus lumborum muscles develop trigger points, as well as the piriformis, gluteals, hamstrings, and erector spinae.

The psoas can torque your spine to the right or left, pull it forward and twist the pelvis into various distortions. Frequently one psoas will shorten and pull the spine and/or pelvis to our dominant side. The distortions of the spine and pelvis can also show up as a short or long leg. This all results in scoliosis, kyphosis, lordosis, trigger points, and spasms in back muscles trying to resist the pulling of the psoas.

It can also pull the spine downward, compressing the facet joints and the intervertebral discs of the lumbar spine. The pressure can cause the discs to degenerate, becoming thinner and less flexible. This degeneration makes the discs more susceptible to bulging or tearing, especially with twisting and bending movements.
#4. What keeps the psoas in contraction?
The psoas will stay contracted because of postural habits and trauma. The way we stand, walk and sit can distort the psoas. If we walk or stand with our chin in an overly forward position the muscle will tighten. Sitting through much of the day at the office, car or elsewhere causes the muscle to shorten to keep us bio-mechanically balanced in our chairs. Over time we develop a “normal” way of holding the psoas that is dysfunctional. Unresolved trauma can keep the psoas short and reactive. This is a primary muscle in flight, fight, freeze or fear responses to danger. When survival is at stake, it propels the body to hit the ground running. When startled, it ignites preparation of the extensor muscles to reach out (grab hold) or run. Until the psoas is released the muscle may stay contracted and go into further shortening and spasm very easily.

1. Skill

Pick something that’s been giving you a hard time and practice

2. WOD

amrap 15

50 dbl unders

40 kb swings 1.5/1

30 sit-ups


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12 Comments on “Thursday 9.8.11”

  1. Josh Says:

    Nice! This is a great explanation! Along with core instability, I see this as a primary contributor to back pain all day long in practice. Much low back, and upper back, dysfunction and pain can be avoided with dynamic hip flexor stretching and mobilization exercises! This is great Gil!


  2. amy Says:

    yep. it’s an important muscle.
    we beat the snot out of it with all our squats, wall balls, thrusters, cleans, running, lunges, box jump, foot to bars/knee to elbow … no. it’s not just your glutes, hamstrings and quads that are getting trashed doing these. check your adductors, too (those inside the thigh and groin muscles). they often tighten and “silently suffer” in conjunction with the psoas.


    • Tiffany Says:

      great point, Amy…and an excellent article, Gil. I like to stretch my psoas before working out, and again at night before going to bed (usually following a day of being the car and seated at a desk).
      I tend to do standing leg swings, deep lunges with arms overhead and/or twisting, and a lunge in front of a wall (front knee at 90 degrees) with the back knee bent such that the shin is against the wall (holding for 30-45 seconds) prior to workouts.
      At night, I begin with a passive release while lying on the floor, with knees bent and feet hip width apart, allowing my muscles to relax and bones to sink into the ground. I continue by bringing one knee into the chest, while maintaining a neutral pelvis, and slowly extend the opposite leg on the floor. After holding this stretch for about 30 seconds, I externally rotate the leg that is into the chest and pull the foot toward toward the chest so that it is in line with the knee (one hand is on the outside of the knee, the other on the outside of the ankle), shoulders curled off the floor to hold this position which is like pigeon in yoga, but supine. I finish with my heels together, knees open outward in a reclined butterfly pose, allowing the hips, adductors, and psoas to release fully.
      Doing these stretches have really aided in my recovery from grueling workouts and help keep my psoas (and sore ass) in check.


  3. Gilaad cohen Says:

    Remember fellas, a supple psoas can help in the sack as well 🙂


  4. Tiffany Says:

    Skill work: negative deadlift 5X5: 95#, 115#, 135#, 145#, 155# (only 4 reps)
    WOD: 4 rounds + 50 + 40, a total sweatfest!


  5. Staci Says:

    “the psoas is functionally the filet mignon of the human being” 🙂


  6. Michele Says:

    4 + 27 rx
    kb swings were rough. forearms were burning.


  7. Heather Donnelly Says:

    3+14 rx. That kettlebell felt way heavier than it usually does.


  8. Robert Rykowski Says:

    2+150+32, did singles, another rough day. friday rest will be great!


  9. Joel Says:

    In keeping with my tradition, I did yesterdays WOD. DL – 1 set of 5 @ 225, 4×5 @ 265. Box jumps 37in, 38in x 2, 39in, 40in. Tomorrow, I’ll break tradition and do Friday’s WOD.


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