If the iliacus could speak, I think it would say something like this:

“Why does the psoas major get all the attention?

Really, did I do something wrong? Because last time I checked, I’m a muscle too. Sure, I may not have as many attachments as the psoas and yeah, I only connect the pelvis to the lesser trochanter. But did you check out the size of my attachment on the ilium? That’s substantial.

Don’t know what happened, but first we were inseparable. Anatomists lumped us together and actually referred to us as the iliopsoas (some still do) because we share a tendon that attaches to the femur. And then we got separated and now the psoas gets all the attention. All I hear about is psoas, psoas, psoas.

Pain in your hip? must be the psoas! One leg is longer than the other? Must be the psoas! Lateral bend in the spine? Must be the psoas! I mean look at me, I am a sizable muscle that packs a lot of power! And I have one function which makes me stronger (muscles with more than one function and multiple attachments tend to be weaker). I can’t get no respect!”

That’s what I think the iliacus would say. And for some reason I think it would say it with a Jersey accent.

Maybe it’s time to give the iliacus a little more attention!

I rarely paid much attention to the iliacus. I read so much about the psoas (there are a bunch of books and articles written about it) and while I still think that the psoas is an important muscle to know, the iliacus deserves attention too. Just to reiterate – muscles with more than one function at more than one joint (like the psoas) have to distribute their force across different lines of pull and therefore tend to be weaker than muscles with one function. The iliacus has a large and powerful attachment on the inside of the ilium. That gives it a lot of leverage to do its one job – which is to flex the thigh at the hip joint or anteriorly tilt the pelvis if the thigh is fixed.

I thought I was all smart with my anatomy knowledge. I walked into my appointment with my orthopedic massage therapist thinking that the tightness I was feeling along parts of the left side of my body were due in large part to a tight psoas on that side. I talked the talk with my OMT and when it came time for him to assess me I said – “you think it’s my psoas, right?”

“Nope!” he said. “Your psoas isn’t really working on that side. It’s weak and it is being inhibited by your iliacus. Your iliacus is the culprit. That is what is tight.”

We did a test which illustrated the huge difference from my right psoas to my left. I was shocked. And ever since then I have been paying a lot of attention to my iliacus. So here is the skinny:

The iliacus attaches on the internal ilium and the lesser trochanter of the femur. It is a powerful muscle that flexes the thigh at the hip joint (the iliopsoas combined is the most powerful hip flexor). It also laterally rotates the thigh at the hip joint but this is a weak action for this muscle. Its primary role is flexing the hip.

Tune back in on Friday for some tips to stretch and strengthen the iliacus!

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Ariana Rabinovitch

After 20 years of practicing yoga Ariana has come to believe that body-consciousness leads to self-healing and self-transformation. Ariana teaches a therapeutic style of yoga and often incorporates non-traditional yoga postures and exercises in order to strive for a balance between strength and flexibility. She brings her extensive knowledge of Anatomy and Kinesiology to the forefront of her teaching. She began with an Iyengar yoga program at Columbia University and since then has learned from a wide array of incredible teachers (including Jill Miller!) in order to get a well-rounded and diverse understanding of Yoga.

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Kat Waters

What a great educational and funny read to bring this muscle to life and it certainly got me thinking more about this muscle and how, like you say the psoas gets all the attention. This has prompted me to investigate this muscle further and embody it in my body; thank you.


This article is awesome. Such a nice read. I have always been keen on knowing what the Iliacus does and how it differs from the Psoas. I have a similar feeling of tightness in my right side as you describe in your article. I feel it especially on the inside of my right ilium crest. And I didn’t know that the psoas could be inhibited by the iliacus. By the way I have pretty bad difficulties with flexing my right hip, too… So I guess I would be a good idea to check my iliacus and see what it says… Read more »

Noelle Carvey

Well I want to find the article on specifically stretching the iliacus. This was fabulous and hilarious. I had to screen shot your beginning Jersey iliacus dialogue because it is gonna help me remember those points just be sheer amusement. I’m in that process of figuring out the root of a couple little nagging beginning signs of something off in a few areas and realizing that there are so many other key muscles involved that deserve the attention to has been so wonderfully eye opening. I say to myself to always look at the bigger picture but there is always… Read more »


If my iliacus is sore and inflamed, should I avoid rolling on it / massage? What is the best way to care for it?


Haha, love learning about this muscle from the muscle’s emotional perspective. I’m going to have fun palpating and learning different ways to massage and stretch the illiacus! Thanks for sharing!

Eva Jedlovsky

Love how you combined entertainment and education, very fun piece to read. You made me feel the pain of the overlooked iliacus. Your explanation of the difference between muscles with one or multiple attachment was very helpful as I continue with my Yoga Tune Up training.

Cintia Hongay

I blame it on evolution and how we became bipedal. My cat and dog are so happy on all fours because they have a different relationship with their iliopsoas muscles. It is true that the psoas is major as it is basically the one that keeps the upper and lower body flexing and extending respect to one another and it keeps us upright, and the wear and tear of walking misaligned and sitting with bad posture and numbing our glutes… yep! These two need constant TLC.

Kimmi Ott

great article…need to read the follow up…my wheels are turning!! thank you!

Kate H

I can agree that the Iliacus should have a Jersey accent. Partly because we “Fuhgeddaboudit.” I appreciate your sense of humor in bringing awareness of a forgotten muscle. I have to pull out my book on muscle testing out of curiosity now.

Tracey Silverman

I learned so much from this entertaining article on the illiacus, especially that muscles with only one function are stronger than muscles with more than one function. Fascinating stuff! I often wonder if sensations and tightness is coming from my psoas or from my iliiacus, and you are so right, the psoas always gets the attention. What test did your massage therapist do to test your psoas strength? I’m curious to test mine. I’ll have to ask my PT, too!


I couldn’t agree more and been thinking along similar lines myself for a while, greatly put across and an enjoyable read 🙂


Thanks for the entertaining take on an eye-opening topic. You’ve gotten me interested in NKT for sure, not to mention learning more about distinguishing how we (and how our yoga students) use these two muscles distinctly. Would you happen to have suggestions for further reading/learning?


Hi Grajee,

Sorry to hear you are in pain. Because of your herniated disc and nerve root compression I think it is wise to consult with a medical professional about how best to adapt these movements for you. I always tell clients in situations like yours to work with a quality PT or other medical pro when it comes to that kind of pain. Plus it would be hard to make a recommendation without seeing you and working together to figure out a solution.
Good luck to you and thanks for reaching out.

Gopinath Rajee

Hello Ariana, I bumped into your website while searching for “releasing the Iliacus”. The ART (Active Release Technique) specialist mentioned that my Glutes is being inhibited due the Iliacus. Has asked me to palpate and press on the illiacus for 30 secs before doing a modified Side Lying abduction. I’m suffering a lot and was wondering if you can help with the problem that I currently have.I have herniated disc (and might sill have a nerve root compression) due to which lot of these exercises I’m not supposed to perform. Is there anyway I can do a modified version of… Read more »


Poor iliacus with only one articulating attachment point. It’s still helping to flex the body and share many functions of the psoas. It gets attention once it becomes and “itis” though!


Thank you for such an informative article. I found it very interesting that you mentioned the psoas being blamed for one leg being longer than the other. This is a problem I have, and recently I came to the conclusion that my Psoas is to blame. Suddenly I’m wondering if that is not actually the case, and I am interested in learning more abut the iliacus. Thanks for opening my eyes to another possible explanation!


Christina- The psoas and iliacus share one attachment on the femur. The psoas is much more complex and has many more functions than the iliacus. I don’t know about consciously strengthening one vs the other. In my case I had developed a usage pattern (unconsciously) in which the Iliacus was “overworked” or contracting more/engaged more. In NKT terms I believe that is called facilitated. It was working so hard that it overrode my psoas. In NKT terms, my psoas was “inhibited”. It couldn’t do it’s job because another muscle took on its responsibilities. I have a very basic understanding of… Read more »


Thank you for answering Emil’s question as I was going to ask the same thing. 🙂 But I’m also wondering, because the iliacus and psoas are so closely related, is it really possible to isolate them to strengthen one without the other? Or, are they both strengthened by default.


Emill Kim-
My Orthopaedic MT tested the strength of my psoas on both sides. My left was noticeably weaker. He then palpated the iliacus and found some trigger points which he worked on with sustained pressure and massage. yowzers!


It’s so easy to forget about muscles that aren’t easy to palpate and only have one job. Its hard not to get preoccupied with the “rock star” muscles that get so much attention and thus end up being written about in everything from yoga journals to Muscle & Fitness. Thank you for reminding me to pay attention to my body and not the latest thing.

Lou Shapiro

Excellent! Thank you. I shall give my iliacus a big apology & a great deal more respect, not to mention those of my students.


This blog made me smile because I STILL refer to the hip flexors as the iliopsoas in a large, group setting, It was nice that you delineated the function of the iliacus, where it attaches and how it can actually be a greater source of tightness/pain than the psoas. I constantly suffer from tight hip flexors due to my “desk day job” so it’s nice to know that I should show equal attention to strengthening and stretching these two muscles.

Aaron Porter

Great Article! I had a teacher tell me that the Iliacus is really the “King” of compensation. So I view it as royalty sometimes. 😉 So many people have weak psoas’s and have a facilitated Iliacus. I love to use the Alpha Ball to work on my Iliacus and simple psoas strengthening exercise to create balance.

Emill Kim

I always understood that the muscles were intercalated, similar innervations in places, and often worked in concert with strong stimulation (ie runners and cyclists) leading to flexion of the thigh but also a bit of spine flexion. How’d did your massage therapist discern that it was just your illiacus alone? Palapation? strength test? I’m Curious.


For years I always heard cyclists complain about their tight hips because of their psoas. It was the easiest muscle to blame because that was all everybody complained about. Now we can include the iliacus.



I think my tight hip was he result of an ankle injury on the other leg. So watch out for issues on the other leg/hip not necessarily the one you injured.The body is brilliant at compensating while recovering from injuries, but doesn’t always know when it’s time to stop or how to go back to healthy balanced movement patterns.


Jason Campbell

I broke my ankle almost a year ago and it’s caused major tightness up my leg and thrown my hips a curve ball. Even though i was aware of the Iliacus, i just never really thought about how that could be part of the problem. I’m not sure how i missed it considering it’s attachment to the iliac crest!!!

Thanks for helping to re-open my eyes.



THanks for your comment. Glad you appreciate my sense of humor 😛




Oh I wonder what the psoas’ personality is like too. That would be fun to explore. Maybe a diva? To answer your question – not sure how I would tell others not to end up in the same predicament that I did. I would never have known had I not been to my OMT. For me it was a result of my body healing/overcompensating from an ankle injury I had on the right side.




My OMT is trained in NKT – NueroKinetic Therapy (which I am looking into myself…very cool) which uses manual movement tests to see if a muscle is facilitated or inhibited. Facilitated muscles not only can contract but can also start to do the work of other muscles thereby inhibiting/weakening them.


Barbie Levasseur

Who knew the iliacus was so sassy 😉 So, how would someone avoid ending up in the same situation as you did? How do you keep the iliacus and psoas working together in harmony? (Dare I ask what the psoas’ personality is like?)

Caitlin Vestal

This article made me realize that I don’t think I’ve ever really thought about my Iliacus…yikes! The psoas does get so much love and attention, but I don’t know that I’ve ever had a teacher other than Jill mention Iliacus to me. I’d love to know more about how your OMT determined it was your iliacus that was tight–via palpation or a movement test? Thanks for getting me thinking about this unsung muscle!


I have been thinking about my iliacus – I suspected it’s role in my inability to get my “straight” leg to completely straighten in Half-Happy Baby pose today, then came to read some blog poses while watching the unfolding New Jersey bridge story on Rachel Maddow, and got a great laugh at the Jersey-accented iliacus having a say. Your second piece confirmed my suspicions about my tight iliacus, and took me back to classes years ago with my main yoga teacher, who directed my attention to this muscle repeatedly. Time for some serious revisiting – I think some attention to… Read more »

Nancy Drope

Looking forward to the stretch and strengthen post .Thanks ! Glad Iliacus is speaking up !


Great article, and what a clever way to write it! I can’t wait to hear your tips for addressing the mighty illiacus!

katie in montana

looking forward to the next blog for those exercises!

Helen Mcavoy

thank you ! I have similar issues on my left side…trying to fugue out…was just reading lots of psoas material… But you have given me new direction of where to venture…I will be on the edge of my seat(properly aligned…) waiting for the next blog!

Yvonne Duke

I shall never overlook my iliacus again. Here I was giving all the credit and paying all my attention on the mighty psoas. I love these blogs because they keep me thinking and growing in my knowledge. I am looking forward to the exercises you propose in your Friday article.

Kate Krumsiek

You are so right, Ariana! The illiacus is like the wallflower best friend who never talks to anyone at the party – by reputation at least. Thank you for clearing that up. I LOVE the idea that a muscle that does fewer jobs is stronger than one that does many. I’ll be mulling that over and figuring out what that means for my body and my students’. Thanks for again bringing a new perspective to my thinking with your smarts!! xo