Tuesday, December 14, 2010

What is this mysterious animal called Sacral Nutation?

In her recent post, Claudia asked a question that has been at the back of my mind for some time now: What is Sacral Nutation? I have been practicing a whole bunch of backbends (including, of course, the famous kapotasana) for some time now, but I honestly still don't know if my sacrum is actually nutating (Is this the right verb? Well, you know what I mean...) in those backbends.

There is, of course, no shortage of authoritative and detailed anatomical descriptions of sacral nutation out there. Gregor Maehle, for example, describes it as involving the sacrum moving forward relative to the pelvic bones, almost independently of the pelvic bones (I don't have his book handy here, but this is what I remember).

But honestly, I think there is one problem with just relying on anatomical explanations; they are practically useless from an experiential point of view. I mean, unless one knows what sacral nutation actually feels like in the body when one is doing a backbend, no amount of anatomical description, no matter how detailed, will help. This is particularly true in a backbend, because one can't see where one's own sacrum is in space when one is in the backbend. So what we need is a description of what sacral nutation feels like in the body of the practitioner.

So I emailed Kino earlier today, in search of the answer to this nagging question. To my great joy, she responded earlier this evening. Here's what she says,

"Sacral Nutation is something very important for deep backbending. You need to tuck your tailbone in order to send the pelvis forward over your feet. But if you tuck your tailbone too strongly then you will flatten lumbar spine and prevent you from going deeply in backbends. It's a fine balance. Only with strong moola bandha and uddiyana bandha combined with a careful flexion of the back muscles will you actually be able to nutate the sacrum. When you do it will feel like an allowing and a releasing into a depth in the inner space of your pelvis and magically more space around the lumbar spine and sacro-iliac joints."

The last sentence is the key: One needs to feel the openness in the inner space of the pelvis. This is important, because it is physically possible for one to achieve a deep backbend by flexing the lumbar muscles and gluteus maximus too much without engaging the bandhas. When one does this, backbending becomes very laborious and difficult, and lower back pain results. So, sacral nutation and deep backbending involves combining the work of the gross muscles (what Kino calls the "careful flexion of the back muscles") with the work of the finer musculature (the bandhas). 

I hope this is a helpful contribution to unravelling the mystery of sacral nutation. If you successfully nutate your sacrum in a backbend, your backbend might look a little like this: 

At the risk of being very immodest, this is, of course, yours truly in the famous kapotasana :-)


  1. Nobel, at the risk of arguing with Kino, she is describing nutation inaccurately.
    please read again what i posted on Claudia' blog. what Kino is describing is counternutation. i suppose it is mere semantics. but to be able to understand and possibly control this, everyone needs to be able to be on the same page using the same words accurately.
    additionally, i would argue that counternutation (the apex or bottom of the sacrum 'tucking' while the base or what is actually the top of the sacrum moves backwards of the ilium) is not the only way folks can get into deep backbends. i am fairly certain i nutate, or tilt the base of the sacrum forward while the apex moves up and back, at least for part of my backbend.
    i actually think without knowing the specific musculature that is at work in either of these situations, the movement of the bones is almost irrelevant. and i unfortunately can't really speak on that with confidence.

    again, i would encourage EVERYONE to purchase the anatomy of hatha yoga, i clearly need to get another copy because mine has been loaned out and not returned. but it explains this process brilliantly.

    lastly, i will go out on a limb and say, that an 'advanced' backbend has a lot less to do with understanding sacral nutation, than the actual structure of ones own pelvis, ones own SI joint, and ones own hip joint. and these are not things that we are able to change.

  2. Interesting, Tova. This might be because I don't know my anatomy very well, but I honestly fail to see just how your explanation is different from Kino's.

    From what little I do understand, it seems that your main point of disagreement with Kino's explanation is that while Kapandji describes the motion of nutation as involving an anterior inferior motion of the base of the sacrum, Kino talks about "tucking the tailbone to send the pelvis forward," which might be taken to suggest that she is contradicting Kapandji, since "tucking" might suggest posterior motion rather than anterior motion. Do I understand where you are coming from?

    At the risk of making things more complicated, allow me to make a little suggestion: Is it possible that Kino and Kapandji are actually talking about the same thing? Maybe when Kino says "tucking", she does not mean "posterior motion", but something along the lines of "stabilizing"? Perhaps "tucking" serves the function of stabilizing the sacrum as it moves forward relative to the PSIS? At least, that was how I understood her.

    I should not say anymore; I'm clearly out of my depth here. But that's why I ventured to ask Kino to say something about how the pose feels from the inside, rather than simply give an anatomical explanation (I'm not saying that anatomical explanations are unimportant). I suspect that most people (myself included) rely on certain feelings or "cues" from their body when they go into the posture to give them feedback as to whether they are doing the pose correctly. I believe that these cues are at least as important as anatomical details: I can't speak for other people, but I don't ask myself questions like, "Is the base of my sacrum executing an anterior inferior motion?" as I am going into kapotasana, for instance. I'm not saying this to be mean, or to downplay the importance of anatomy; but it is what it is.

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  4. Thank you :-) Finally found an excuse to exhibit my "favorite" posture online.

  5. Great picture Nobel!, and thanks for sharing Kino's words!

  6. By the way, how lucky are we to have Kino here and D. Keil back at my blog helping us discern....!!!

  7. Thanks Claudia! Yes, I think the blog is a wonderful resource, especially for people like me who mainly practice by themselves.

  8. hi nobel,
    i removed my second response up there because i felt like it might be rude and confrontational, which i did not mean to be.

  9. No problem at all, Tova. I didn't find it rude and confrontational at all. I think that many people (including you and I) have very passionate views about the practice and related issues, and the passion just shows in the writing.

    If you feel like it, you are more than welcome to re-post your second response :-)

  10. thanks Nobel. i think David Keil explained it perfectly over on Claudia's blog, so i am good :)

  11. Great pic of Kapo, Nobel. Thanks for sharing. I hope to get mine there some day.

  12. I wan't going to comment because I know nothing about this nutation topic, however I second with abreathingpractice that it's an awesome pic and I hope to get that pose some day. Right now just looking at that picture hurts my back :) :) :)

  13. Thanks, abreathingpractice and Yyogini! With patience and consistent practice, you will definitely get there.

  14. I think some of the confusion (for me anyway) stems from the fact that the base of the sacrum is actually the top of it (the wider part), not the bottom? Kino obviously knows what she is talking about, but I *think* she may have meant to say *counter-nutation* is very important for backbends. That would put her in agreement with David Keil, I think?

    Relating this to my own experience, it seems to me they are both describing the action of not allowing the SI area to get crunched in backbends by engaging mula bandha strongly which brings the tip of the tailbone forward relative to a fixed pelvis. The tailbone over time starts to feel like it drops forward and down between the legs, creating length. Super important, but equally important is moving deep into the fronts of the hip flexors to create more space for the area as a whole.

  15. That sounds right, susananda. It's interesting how we bend ourselves all out of shape (no pun intended) over using different words or phrases to describe what is essentially the same phenomenon. For instance, as you point out, the "base of the sacrum" is actually the top, or superior part of it.

    Biologists believe the tailbone is an evolutionary vestige of something we used to have (tails); as such, it does not serve a functional purpose in the human body. I sometimes wonder how different back-bending would be if evolution did its job properly, and got rid of the tailbone altogether. Just a thought...

  16. I think backbending is something where the tailbone still serves a functional purpose :)

  17. Agree with Susan about the tailbone being useful for backward bending. Maybe something almost like a plumb-bob.

    Beautiful kapotasana.

    {out of curiosity, how did you get the reblog/twitter/buzz buttons at the bottom of your posts? I've searched around for a while and can't seem to locate any sufficient info}

  18. Thanks, Portside.

    I'm afraid I can't help with the reblog/twitter/buzz buttons. They just came with the way my blog was set up, so I have no idea how to set them up if they are not there. I'm not very tech savvy, as you can see. The person to ask might be Claudia at "Ashtanga Yoga on Mother Earth". She's a much more experienced blogger.