Everything you Need to Know about Iliopsoas

In our post today, join us and learn about one of your most important lower back muscles: the joined psoas and iliacus muscles, or iliopsoas. So what do you need to know?

Last update: 24 July, 2019

The iliopsoas is a joint muscle located in the hip region. Though usually referred to under one name, they are two separate muscles that merge. Today, let’s take a closer look at the structure, function as well as how it influences physical performance.

The iliopsoas

As we mentioned above, the iliopsoas actually refers to two joined muscles: the psoas major and iliacus. The psoas major starts along the outer surfaces of the lumbar vertebrae (and in some cases, the last dorsal vertebra) and descends diagonally behind the retroperitoneal organs such as the kidneys.

Meanwhile, the iliacus muscle starts along the inner border of the ilium and merges with the psoas major. The joint muscle crosses over the inguinal ligament. They’re combined into one tendon and insert on the lesser trochanter of the femur.

Function of the iliopsoas

The iliopsoas muscle group is extremely important as it helps you walk and maintain posture. In light of that, taking care of these muscles is crucial for maintaining good posture.

Below, read the main functions of the iliopsoas:

  • As you walk, the iliopsoas lifts and flexes the lower muscle area. Raising your leg sets these muscles in motion. It also permits them with the abduction and external hip rotation movements.
  • Stabilizes the lumbar spinal region, especially the psoas major muscle.
  • Plays an important role in controlling the extent of lumbar lordosis.


As with any muscle in your body, overexerting this muscle group can lead to contracture. Iliopsoas contractures are common problems in people who are starting a new sport that works out the muscle region. Examples might include endurance sports (cycling or long-distance racing) or weightlifting.

Overexerting these muscles can lead to over-activation and shortening of the muscles. The resulting discomfort can be remedied with a “tucked in” posture or by sitting down. On the contrary, if you try standing upright with an injured iliopsoas, you’ll notice sharp pain, because the muscles are stretching beyond their capacity.

Furthermore, an injured iliopsoas will have consequences on your athletic performance — even on everyday walking. Taking this into consideration, we recommend resting until symptoms improve.

In addition, overworked iliopsoas muscles often imply more stress on the back and a more serious extent of lumbar lordosis (hyperlordosis) as a result of the shortened muscles. Consequently, these combined factors can cause back pain and lumbar contractures.

Stretching as a preventative measure

Stretching the iliopsoas region correctly, especially after working out, is essential for keeping it safe and healthy. We recommend the following stretches. They can really come in handy to prevent overworking the muscles or to relieve them if they’ve already been pushed past their limit.

But if your case relates to the latter, we strongly recommend contacting a physical therapist. A professional will be your most reliable option for recovery.

Exercises for stretching the iliopsoas

Our first stretch is simple to do and you won’t need anything other than a flat surface to stand on. First, stand in a scissor position where one leg is behind the other and your weight is shifted on the back leg. Bend the leg in front at a 90-degree angle. Keep your back leg firmly planted, parallel and straight all the way down.

Your waist should be relaxed and your core completely upright. Let your body weight bring you slightly forward and let your waist follow.

iliopsoas stretch one

For our second stretch, start in the same position as the first one. Bring the palms of your hands down onto the floor. Place them at each side of the leg you have in front.

Now, get into the following position: front leg, the arm of the same side as the front leg, opposite arm. Hold the position for around twenty seconds.

iliopsoas stretch two
Image: YouTube Albany CrossFit

Next up is our last stretch. You’ll need a little flexibility but it does a great job stretching out, not only the psoas major muscle, but nearly your entire body as well. Once again, start out in the same position and lift the arm that was in the center (the arm on the same side of the front leg).

Flip over your hand so that your palm is facing upward and keep your arm in line with your other arm that’s on the floor. Keep your eyes on your fingers of the arm you have in the air during this entire stretch.

All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.

  • Harvey LA, Katalinic OM, Herbert RD, Moseley AM, Lannin NA, Schurr K. Stretch for the treatment and prevention of contractures. Cochrane Database Syst Rev [Internet]. 2017 Jan 9 [cited 2019 Apr 23]; Available from: http://doi.wiley.com/10.1002/14651858.CD007455.pub3
  • Franke H, Fryer G, Ostelo RW, Kamper SJ. Muscle energy technique for non-specific low-back pain. Cochrane Database Syst Rev [Internet]. 2015 Feb 27 [cited 2019 Apr 23]; Available from: http://doi.wiley.com/10.1002/14651858.CD009852.pub2
  • Sajko S, Stuber K. Psoas Major: a case report and review of its anatomy, biomechanics, and clinical implications. J Can Chiropr Assoc [Internet]. 2009 Dec [cited 2019 Apr 23];53(4):311–8. Available from: http://www.ncbi.nlm.nih.gov/pubmed/20037696

This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.