Course Notes: PRI Myokinematic Restoration

What a Class

Wow. That’s all that really needs to be said.  I have had a great deal of exposure to PRI in the past, but I have only had one formal class under my belt. Needless to say, I was looking forward to learning more. James Anderson and the PRI folks did not disappoint.

Myokinematic Restoration was easily the best class I have taken all year.

It also helped having another like-minded group attending. You learn so much more when you are surrounded by friends. Here is the course low-down.

Disclaimer for the Uninitiated

I know there are a lot of misconceptions about PRI on the interwebz. Even though posture is in the name, PRI has little to do with posture in the traditional sense. We know posture does not cause pain, and PRI agrees with this notion. But it’s not like they can change the name of the organization now. What? Do you think Ron Hruska is Diddy or something?

After discussions with James and his mentioning this aloud in class, the target of PRI is the autonomic nervous system. Not posture, not pain, not pathoanatomy, but the brain. Essentially, they have figured out a window into the autonomic nervous system via peripheral assessment.

Moreover, PRI is not in the pain business, though many think this is the case. Hell, even in the home studies they mention pain quite a bit. But realize those were done in 2005. Would you like me to hold you to things you have said 8 years ago?

Throughout the entire two day course, pain was mentioned in two instances. The first time was this direct quote from James:

“ PRI does not treat pain.”

The second time was mentioned in the case of various pathologies, in which James put a disclaimer that PRI just puts these things in here per clinician requests.

What PRI treats is position, neutrality, a state of the autonomic nervous system that is shifted towards parasympathetic but can freely alternate between sympathetic and parasympathetic states.

So if PRI doesn’t treat pain why use it? I say because the autonomic nervous system influences pain states. The potentially indirect effects on pain when the autonomic nervous system is favorably influenced seem desirable. And from my own personal experience, for whatever that is worth, my limited understanding of PRI has netted me quite a bit of success with my patients. It also requires my patients to spend less time in the clinic since they do not require my hands; good news for everyone.

Back to the Basics

The basic PRI concepts rely on asymmetry. All body systems –neurological, respiratory, muscular, visual, etc.—are asymmetrical.  This asymmetry cannot be changed, but we can strive to reduce one-sided dominance as best we can.

The side that is dominant in human beings is the right side. This lateralization is normal, but what we don’t want is the right to be overly biased. Too much right dominance essentially creates a low level left sided neglect.

The Chain

Myokin’s utmost focus is on a polyarticular muscle chain known as the anterior interior chain (AIC), which is composed of the following muscles:

  • Diaphragm – king
  • Iliacus
  • Psoas
  • Tensor fascia lata
  • Vastus lateralis
  • Biceps femoris

You have two of these chains, a left and a right. For a variety of reasons, such as our asymmetrical build and left hemisphere/right sided dominance, the left AIC is more dominantly active compared to the right.

You can notice this dominance just by comparing right and left hemidiphragms:

  • Right has a larger diameter.
  • Right has a thicker & larger central tendon.
  • Right has a higher dome, and is better able to maintain this shape.
  • Right has more crural fibers and fascia.
  • The right crura attach 1-1.5 levels lower on the lumbar spine than the left.

Basically, the right diaphragm is built for success, whereas the left diaphragm is often more contracted, smaller, and less concentrically effective. This difference helps perpetuate a more active LAIC. The path of least resistance for you to have an effective breath is by activating these muscles. 

Because the LAIC is the more dominant chain, this throws the body into an asymmetrical position. The left innominate is more anteriorly tilted and forwardly rotated with the right more posteriorly tilted and backwardly rotated. This position puts the right hip into internal rotation, adduction, and extension; and the left hip compensatorily into external rotation, abduction, and flexion.

Chains and Gait

These chains oppose each other during gait. For example, when you are standing on your right leg, your LAIC is active, causing the swing leg to further put weight on the right leg. You cannot fully use one chain unless the opposite chain is inhibited, so the RAIC is quite during this phase. Inhibition allows for alternating and reciprocal gait; the goal of PRI.

Realize that as long as you are in weight bearing, you are in a phase of gait. We can base this off of pelvic positioning. Since pelvic position can be altered with breathing, it is fair to say the every time you take a breath you are put into a phase of gait. Breathing and gait are one in the same.

Pattern Testing

To assess neutrality, many common tests already utilized in the therapy realm are used. The two big tests are:

  • Modified Ober’s test (adduction drop)
  • Modified Thomas test (extension drop)

With the LAIC pattern, you will see a positive Ober’s on the left but not on the right. This finding is due to either restriction from the anterior-inferior acetabular labral rim, transverse ligament, and piriformis muscle; or impact of the posteroinferior femoral neck on the posteroinferior rim of acetabulum that does not allow femoral adduction.

The Thomas test in this pattern can be either positive or negative. A positive Thomas correlates with the adduction drop due to the limited extension. A negative Thomas test, barring a positive Ober, would implicate iliofemoral and pubofemoral ligament laxity.  If we think back to the position of the innominate, the left femur will have to externally rotate in order to face forward, which can stretch the anterior capsuloligamentous structures. Here is the same thing better explained by Bill Hartman:

You should also see limited right trunk rotation (unless there is iliolumbar ligament laxity), decreased left SLR (unless you have an overstretched hamstring), an apparent shorter left leg,  and decreased left hip internal rotation and right hip external rotation.

PRI also has a test called the Hruska Adduction Lift test, which is used to assess acetabulofemoral control in a way that correlates with gait. The scope of this test and interpretations are too much to fully write about in a short summary, so perhaps when I get better understanding all the nuances, performance, and meaning I will post on this test further.  Until then, PRI instructor Mike Cantrell wrote a great piece on the lift test here.

Myokin Algorithm

Taking the above tests, namely the adduction drop and lift test, the goal is to satisfy the following questions:

1)      Can the person adduct? (adduction drop)

2)      Can the person internally rotate on both sides? (Measurement, adduction lift)

3)      Does the person have internal rotation strength on both sides? (adduction lift)

Money Muscles

In order to inhibit the LAIC, there are several key muscles that are to be activated:

  • Left Hamstrings [sagittal repositioner]
  • Left anterior gluteus medius
  • Left ischiocondylar (hamstring portion; IC) adductor [frontal repositioner]
  • Left glute max (sagittal fibers)
  • Right adductor magnus
  • Right glute max (transverse fibers) [Transverse repositioner and the other key to maintaining neutrality].
  • Bilateral obturator interni (the key to maintaining neutrality)
  • Left abdominal obliques.

The goal is to influence the left hemidiaphragm away from its overly contracted state in order to allow better reciprocally alternating respiration, position, and gait.

Treating the LAIC

The LAIC patient has a positive adduction drop test and Thomas test. So the name of the game is to reposition and develop hole control. What hole control means is allowing the obturator and glute max to control the femur in the acetabulum to allow for reciprocal gait pattern.

For the LAIC, we want to activate the following muscles in the following order:

1)      Biceps femoris in ER/extension

2&3)      R Glute max & obturator & adductor magnus via ER

4)      L Anterior glute med via IR

5)      L IC adductor via IR

6)      Medial hamstrings via IR

By performing the exercises in this order, we first reposition, then establish hole control, and then retrain the person to turn to the left side.

Patho LAIC

There are certain instances in which ligaments can get stretched out and become lax. This is where the concept of ligamentous muscle comes into play, in which muscles increase their tone to reinforce capsuloligamentous structures.

The theoretical reason this order is performed is because the IC adductor approximates the femur into the acetabulum, while the left anterior gluteus medius strangulates the joint by further driving internal rotation.

For a patho LAIC, we go for the following muscles in a slightly different order:

1)      Biceps femoris to reposition

2)      L IC adductor via IR

3)      L anterior glute med via IR

4)      R glute max via ER

5)      R adductor magnus via ER

6)      L medial hamstrings via IR

In this instance, we reposition, then build ligamentous muscle, and finish by establishing hole control.

If after a successful reposition you notice mobility changes in hip rotation, you may want to proceed in the following manner:

  • Decreased left IR (v Right): Stretch posterior capsule
  • Increased left ER (v right): go after L IC adductor and L anterior glute med
  • Increased right IR (v left): Kick in R glute max and R posterior glute med
  • Decreased right ER (v left): Stretch anterior & inferior capsule

Favorite James Quotes

  • “The diaphragm owns you.”
  • “If you don’t have position and throw in demand, someone else will do it.”
  • “I find it offensive when people say iliopsoas. We don’t call it the hamductor obturatoridiosus.”
  • “Screw PT school, subscribe to Oprah.”
  • “The whole body is in a phase of gait.”
  • “The problem is the brain and the diaphragm.”
  • “Nobody is Weak.”
  • “External rotation is worthless without internal rotation.”
  • “PRI is from start to finish brain therapy and parasympathetic awareness of the left side.”


I cannot recommend enough courses from PRI. I base this off of the methodology, effectiveness, and thought process. They appreciate the nervous system’s power just as much as anyone. Please check them out and tell ‘em Zac sent you.


  1. Nice review Zac. I took the homestudy, and it’s refreshing to hear the messages targeting the brain and autonomic nervous system. Looking forward to taking it live over thia upcoming year

  2. Zac,
    I got to hand it to ya, I don’t think I’ve ever seen a summary of a PRI course as interesting and humorous as yours was. Even if PR was without merit, I’d want to check out a course after reading your summary.
    Your interest, enthusiasm and sense of humor are much appreciated.
    James Anderson, MPT, PRC

    1. James,

      Your praise means a great deal and is humbling. Glad you enjoyed what you read, and I will champion PRI until I am shown better. See you at I&I.



  3. Zac, I have been exposed to PRI since I was in Grad school at Elon (which was 2003). Honestly, you probably gave one of the best overall explanations about PRI and specifically the Myokin course that I have ever read. I am going to have to go back and reread this post again! I actually just sent this link to my wife, I am hoping to get her interested in PRI so that we can work through it together.
    Having read this review, makes me want to take it over again since I last took it probably 5-7 years ago. The same being said for Postural Respiration. I plan to take Impingement and Instability May 2014 since it will be 20 minutes from my home.

    1. Srharris,

      Thank you for the kind words. Glad I could get you back into the PRI world. Myokin and respiration have gotten nice overhauls in the past 5 years. I am taking I&I in November and hope to have a review of that as well. Hope you get as much out of the courses as I have.



      1. I realize the home studies are older but with pelvic restoration being newer I was considering doing that as a home study . Any experience thoughts?
        I am liking the algorithms now too, especially being only PT in clinic working with PRI it helps. Sadly James is in town this weekend with Respiration but I can’t attend.

        1. I am working my way through it right now, and it is good thus far. I would recommend to anyone doing the home study and the course…just so you can get the nomenclature down at least, then refine and ask questions while attending the course.

  4. Hi Zac,

    thanks for the interesting intro to PRI. As I was working through the exercises I´m afraid that number 4 seams to be disappeared. Would you be so kind to relink? 🙂

    Thanks! Keep up the great work!


    1. Hey Chris,

      Glad you liked the post.

      There was no number 4 in the original post. It was a numbering error. So i reordered them.

      Nice catch 🙂


  5. Zac, is the exercise progression that you show (90/90 hip lift -> L side-lying R glute max -> R side-lying L IR -> etc. the progression that you use when someone presents with L AIC? Or before progressing from 90/90 hip lift would you have a patient do a progression of that, such as 90/90 hip lift with hemi bridge, before progressing to the next exercise. I’m not sure if PRI has matrix for exercise progressions or if its as you listed the 5 exercises here.
    Thank you.

    1. Great to hear from you Sam.

      Short story is “it depends.”

      There are a few ways you can go after it.

      First way (and the one I recommend) is based off of your tests. If the adduction drop is still positive, then you somehow need to reposition. If we are talking a pure left AIC nonpatho, that usually involves a left hamstring-based activity. Something to posterior tilt and backwardly rotate the innominate. From here, the adduction lift tests will guide you the rest of the way.

      In the progression that I laid out, any activity that gets the desired muscles/result shall work. Those were just some of the one’s that I liked. For the hamstring activity (sagittal plane), you could use a 90/90 hip lift or a hemibridge. It’s whatever is best for the patient.

      I would check out the nonmanual CD’s that PRI offers for different exercises. It’s an essential thing to have. They have hundreds. You can get it here:

      Was I able to answer your question?

      1. Thank you, Zac.

        Yes, you did answer my question. Thank you, I appreciate your time.

        I am just getting into PRI stuff. I’ve already taken so much con-ed that I cannot quite budget for the home study courses, yet, so am trying to get a grasp of their system as much as I can until I can budget for their DVDs.

        Do you use PRI methodoloty right out of the gait with a patient, or do you default to anotther assessmetn tool first, i.e. SFMA, and only use PRI if you weren’t able to affect change with your initial assessment and treatment?

        Their ideas seem to flip what I know/thought I knew upside down, so I’m just dipping my foot in, and proceeding cautiosly.

        On another note, I’m finding that most of my patients present as a PEC (Obers B).

        Your website is a great resource.

        Thank you.

        1. Con ed is too damn expensive! You are right on that one.

          PRI influences every aspect of my treatment, even if I am not doing “PRI.” It’s my foundational assessment, thought process, and treatment because it’s a system…the human system. You can’t really classify it as a tool in my book.

          How does it flip all that you knew?

          Most are PECs by the way that I see as well. We are an overextended society in more ways than one.

          1. Hi Zac-

            By flipping some of my previous ideas on their head, I mean, for example, that someone presenting with winged scapulae may not have serratus anterior weakness; perhaps it is faulty position of their thoracic cage (too much thoracic extension). This was an idea I had not encountered before, but have now seen it in some overhead athletes.

            Thanks for all of your replies.

  6. Hey Zac,
    Thank you for posting these blogs. I have been a follower of Bill Hartman, Eric Cressey, Gray Cook, PRI and many more for quite some time now. You are now amongst those inspirational idols of mine.

    I did not get into PT school last time that I applied to several programs, but professionals like yourself motivate to keep fighting and working towards something that I know I was meant to do, which is treating and preventing dysfunction in the human body. I hope to one day meet.


    1. Hey Juan,

      Appreciate the kind words and humbled to be mentioned in the same breath as those greats.

      Keep pushing and stay the course. The hard work and hustle pays off.

      Stay in touch,


  7. Hi Zac,

    Firstly, loving your work- really comprehensive! I have the non manual techniques CD’s at home and are thinking of doing a home course later this year (I live in Australia). I have a few questions on Treating the patho LAIC. With the progressions listed above, and in the CD’s, are you supposed to so them in order each session, ie left obituary or, right glute max, left ant glute med etc.. Or just focus on each one until the respective tests improve?

    1. Hey Shayne,

      Short answer is “It depends”, as there are many influences on testing outcome.

      If we look at things from a pure myokinematic algorithm, the adduction lift tests will guide what the patient needs. So let’s say I get the adduction drop negative and the lift score is a 2/5 on the right. That would tell me this patient needs a right glute max to progress the test. Whatever the patient needs will depend on the test outcome and what they look like from session to session.

      Did that make sense?


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