I am hoping that we do not forget while developing movements for clients that while it is interesting to note the different levels of muscle recruitment from one exercise to another the purpose of an exercise is equally if not more important. The purpose of one exercise to another is the key to strengthening for one person while the purpose of the same exercise for another person may be spinal articulation..... This can lead to completely different benefits at different times...It is interesting isnt it?..

Since when is the oblique a stabilising muscle??

Both the internal and external obliques are VERY important for trunk/spinal stability. They are primarily responsible for lateral stability. Without their activation the transverse provides very little lateral stability and therefore minimal stability overall. University studies have proven through emg and stability testing that general abdominal bracing ('global stabilization') is FAR superior to abdominal "hollowing" (drawing the naval in). The major difference in the two was that the global stabilization allowed proper activation of the obliques, whereas abdominal hollowing often found in pilates causes more isolative contraction of the transverse abdominus and actually inhibits the full contraction of the obliques thus creating lateral instability. The results of the study was quite remarkable... with global stabilization/abdominal bracing proving to be far superior to hollowing (primarily transverse & rectus activation). It's amazing to me that hollowing is still taught in some circles/schools of thought.

The idea of isolating and over-engaging the transverse has been taken too far. The purpose of isolating the transverse in the clinical setting was to re-train its activation in individuals who lost it from injury, surgery, pregnancy or such. But ultimately it was never intended to be left at that. Eventually people are then taught to integrate the activation of all of the abdominal muscles once they re-connect with the transverse. It's the activation of ALL of the abdominal muscles that provides stability, not any single one of those muscles.

This whole idea of artificially separating their function/activation is pointless and dangerous. As is the flexion of the lumbar spine by flattening or rounding the back as it inhibits the multifidi and other posterior muscles of the spine. It also lengthens them past their neutral and thus weakens them physiologically. The lumbars should not be flat or rounded/reversed in curvature during core stability training.... Not good.

I’ve researched all four muscle groups during selected Pilates ab exercises across two studies. All of the abdominal muscles are more intensely engaged during the Pilates exercises I've tested compared to the standard crunch. And, I think that is a good thing for Pilates clients and the gurus.

I do not teach hollowing. Some Pilates exercises recruit certain abdominal muscles to a more or less degree. Any flexion moves like the roll-up and teaser are going to activate the rectus to a marked degree. Moves like the hundred and double leg stretch engage the rectus to a much lower degree and the external, internal ob/TA to a relatively higher degree.

ALL abdominal muscles are important to the trunk both for movement and stability. The rectus abdominis, for instance, is significant in stabilizing the spine when going from sitting to standing. It puzzles me as to why the rectus abdominis has been given a rather "bad name" in some Pilates' circles.

I’ve been sharing (as much I can can) the fact that Pilates moves do not overly isolate any ONE single abdominal muscle...that they effectively utilize all of them (and, again, I’ve measured this). It is a good thing that Pilates exercises are effective at activating the entire abdominal wall and I agree that over-emphasizing the TA minimizes the excellent effect that Pilates has in recruiting more than one muscle.

Michele,

I'm curious if you have much experience utilizing the 'global stabilization' approach to lumbopelvic stability. I would hope to see the old 'crunch/sit-up' approach become obsolete in the near future, if not already. Several studies have shown the global stabilization approach to be more effective and safer than the conventional crunch or sit-up variety and it appears to me that much of the abdominal work in pilates could potentially be of the same variety as the G.S.. ...As long as the lumbars are left in a neutral/naturally mild lordotic curvature and no abdominal hollowing is encouraged.

But from my limited experience the hollowing approach is quite often used by many teachers (drawing the naval toward the spine and dropping the lumbars back moving into flexion). Why are some using the hollowing and others not? Is there a generally accepted standard that teachers are taught to follow? And being that hollowing has proven to be quite inferior for stability through a number of studies, why is it still utilized?

I agree, the rectus abd. is important (maybe for different reasons that aren't commonly discussed though), as much as any other muscle in the body. I do personally feel it's over-emphasized at times as well, along with the obliques. The posterior extensors of the spine, pelvis and legs carry equal importance... Why is it that they don't get nearly the same attention as all of the abdominal muscles. Clearly the extensors of the body, by design and title, are very important to the upright stability of the spine and lumbopelvic region.

If too much emphasis is placed on the rectus abd. it can be of detriment to the extensors of the spine... namely the pars thoracics and friends. Due to the efficient leverage the rectus has on the inferior margin of the sternum/ribcage, it is well poised to draw the thoracic and possibly upper lumbars into flexion. This excessive draw towards flexion necessitates an increase of tonus of the posterior thoracic spine into extension. In my observations, many pilates teachers and students alike often present with a lumbar spine oriented toward flexion and a hyperextended thoracic spine (often they lose the kyphosis in the thoracic and lordosis in the lumbars... consequently also losing their cervical lordosis as well as the neck attempts to relate to the lower segments).

I like to work with the balance between the rectus and psoas, iliacus. Much seems to be left aside regarding these important regions.

One more question, you mention the degree of "intensity" during pilates exercises being higher... During your studies, are you equating stability to the intensity of the engagement or the co-contraction/coordination of the engagement?

Respectfully,
JW

Dear JW:

If you are asking me about McGill's research and "bracing," then yes. I've been following that line of research since his earliest papers. A colleague of mine and I teach the bracing method when doing workshops and/or consulting with athletes.

There has been debate whether it's important for the TA to engage first before the rest of the abdominal muscles for spinal stability. I believe this comes from some of Hodges early work where they found that people with low back pain had a delayed activation of the TA and, thus, the other musculature (is/was theorized) to have to play the roles of both stabilization and segmental movement such that the lumbar spine's stabilization was sacrificed.

One, more recent study, found that when employing bracing before curling versus hollowing before curling, the onset activation timing was significantly different for the TA: The TA was activated before the rest of musculature during the "hollow and curl" protocol. While the TA was also activated before the rest of the musculature during the "brace and curl" protocol, the onset time was not (statistically) significantly different between the TA and the other muscles.

...I believe this is (at least part of) what contributes to the whole debate regarding the two techniques, despite the fact that bracing provides a coordinated effort provided by the trunk musculature, a wider base of support (for stability and function), etc. etc. (as you already understand).

I also think that strategies for low back pain have often been superimposed on much of the Pilates' methodology? Why? A very good post started last spring (I believe) addressed whether Pilates is/should be a form of "bodywork" versus a system of exercise (and whether Pilates instructors should be utilizing the Method for "bodywork" altogether). Hence, from what I've observed, many therapeutic/bodywork strategies (and often-times not necessarily current ones) are incorporated into the work - "hollowing" definitely being one.

Perhaps the foregoing may help to explain why we often see hollowing still used extensively...These are my thoughts and observations thus far.

I agree that extension/extensor work and balance in the hip and lumbo-pelvic region is essential and, further, with respect to the relationship to the spine.

In terms of "intensity" - I'm simply talking about the actual voltage produced by the nervous system supplying the musculature being assessed. The standard crunch is often used as a criterion in many studies and/or intensity is reported with respect to a maximal voluntary activation for the selected muscle (i.e., the Criss-Cross produces a level of activation, on average, that is 60% of MVC for that muscle, etc.). Therefore, we commonly look at intensity of activation based on maximal output, or, with respect to other movements/exercises (for standardization).

I appreciate your comments, questions, and passion in all of these regards and perhaps your thoughts why we see so many "hollowing" cues...

Sincerely, Michele

I agree with sue aglietti huntley’s succinct answer above. Movement has so many aspects; it’s all very interesting….

Suppose a new client, who has practiced pilates for a while, begins moving and I see she appears to be “drawing in her navel.” I ask her what she is doing. She says she is hollowing, as her former teacher taught her to do.
I note that I may or may not call what she is doing hollowing.
I also note that I was not present when her former teacher was teaching hollowing to her, as she has interpreted it.
1. The move she is doing could be just right for her body. It is balanced, aligning, and supportive to her overall make-up.
2. The move she is doing may be adequate for her body in that moment, but may not be appropriate if she performs it in a different tempo, in another plane of motion, or in that way the next day.
3. The move she is doing is causing an imbalance, even though she is not in pain.
4. The move she is doing is potentially harmful being that she is in pain.
The above scenarios (and many variations in between) offer the possibility of conversation and client experience. If I begin with an idea that my client’s idea of hollowing—or her former teacher’s idea of hollowing—is wrong, there would be no conversation.

Ms. Olson’s work is very helpful in informing those coming from a different movement language base what we experientially and intuitively do as pilates teachers. Thank you for your work and for the validation, Ms. Olson.

I appreciate your response Michele. I'm can understand more clearly based on what you stated, however I don't necessarily see why the super-imposition was put on pilates given that most teachers would not have the education, scope or understanding to recognize when the TA would need to be focused on in such an isolative manner... The occurence of TA activation dysfunction isn't frequent enough to warrant doing it with everyone who walks in the door. I personally feel it may be detrimental to break down someones current co-activation ability when it is not dysfunctional to start and try to make it work in isolative chunks. What about working with what's already there... ? I just seems to me that we're trying to re-teach everyone how to move and breath with such effort and control that it diminishes the autonomic capacities that define 'optimal and efficient' function.

I do agree that various approaches will serve different people and at different times. However it is very obvious that this abdominal hollowing is consistently used throughout pilates by many teachers, without an understanding of why it may benefit someone intitially. At some point they should be more integrative and functional, leaving the hollowing as an initial tool to re-learn TA activation, if even necessary in the first place.

And I don't know if I quite understood what you were saying Michele on this, but it's my understanding from clinical and personal experience alike, in addition to the work of Hodges, McGill, Lee and such, that stability is not defined by the strength of the contraction relative to the MVC, but by the coordinative timing and function of ALL of the muscles, including the posterior spinal musculature and the legs/pelvis alike. All the emphasis on the abdominals seems really misguided to me. The abdominals are only one small portion of this equation. And given that people often spend their days sitting down in some capacity, it seems even more important ot be focusing more attention on the extensors of the body rather than the flexion dominant abdominals. Why work so diligently on getting the body strong in the direction of flexion when flexion is the very direction that pulls us back to the fetal position?

Just some thoughts...

Yes. Stability is the coordinated effort of many musculature. It seems when Hodges' early research was brought more into the mainstream, many exercise teachers went the "way of drawing in" as "right" for abdominal exercise, and other approaches (such as concentric flexion work) went "out the window." ...Far too "black and white."

Also with further regard to stability, the output of the involved musculature need not be all that high. A coordinated effort at about 30% of MVC that is maintained during movement appears to be adequate and suits the fiber types comprising these muscles.

An activation that is too high can compress the spine, for example, and be too stiff. Regardless, to assume that "drawing in" is the key to Pilates is such a narrow interpretation and application. Further, the idea that all flexion exercise are bad or extension exercises are bad, etc. etc. is also too narrow.

I appreciate if any of our lab's research contributes to the knowledge-base (to those of you who made such comments - I thank you). Still, the interpretation and application is at least as significant if not more.

Thank you so much for all thoughts.

Sincerely, Michele

I'd agree.

Thanks for your ongoing work and efforts... (& for responding to my long-winded comments and questions).

Respectfully,
jw

Well trained Pilates teachers don't use Spine to Mat, only the scoop/hollow, or navel to spine. Joseph Pilates thought that the spine should be completely straight, like a plump line, so he taught Navel to Spine, Spine to Mat. Obviously, we know today that if the spine was completely straight, we couldn't stand. So, very few teachers still teach spine to mat. (I think some Classically trained teachers in NYC do, but only those who insist on following Joseph Pilates teachings to the letter. ) However, some clients with extremely weak abdominals or excessive lumbar lordosis need to bring their lumbar spine more toward the mat when engaging the TVA to begin protect the spine while building strength. As they build abdominal strength, the abs should be worked in a neutral pelvis/spine position.

I find most clients didn't even know they owned a transversus abdominis muscle, let alone how to activate it. Most of the time when I am trying to get someone to activate TA they immediately fire into obliques. We attempt to work all abdonminal muscles to a balanced degree. I find it difficult to believe that overtraining the TA is such an issue. I believe it can be overtrained, as any muscle could be. But, how many people have you seen with an overtrained TA? This is an honest question. I have never experienced that as an issue. Only the opposite.

Dr. Olsen,
I had another question re: “Any abdominal exercise that requires full flexion of the trunk away from the mat will always rely heavily on the outer layer rectus abdominis,”

I just got up off of my office floor after trying to isolate obliques in a roll up, and feel like I can actually emphasize flexion with the obliques if I put the intention there. I understand rectus is going to do a huge amount of the work, but could the degree of any muscle use be entirely dependent upon the knowledge and body awareness of the individual?

Thanks so much for your research. I look forward to hearing more from you as you complete more studies. Keep up the good work!

Hi Dr. Olson, I've been trying to sort out this "hollowing" versus "bracing" debate, and to be honest I'm just getting more confused. I suggest the debate could be simplified by leaving out this terminology, and focus on one simple question: If, for example, someone is doing "the hundreds" as in the picture above, then should their lower back be in contact with the floor? Would you be kind enough to advise me? Speaking personally, if my lower back were not in contact with the floor, the exercise would feel loose and incomplete.

Thanks in advance, Chris