Below is a paraphrase of a Facebook Chat I had with a good friend and excellent trainer who asked me to explain the Core Pendulum Theory. For congruency, his questions are in italics.
My upcoming DVD, Training = Rehab, Rehab = Training, will have a good 30-45 minutes explaining this concept with slides. I think this brief post may enhance the explanation of the concept(s).
Think of a necklace with a pendant holding it up in front of someone to make them hypnotized. The position of rest, of comfort, of minmal effort is the necklace hanging straight down.
This position of “stability” is what it is because the inherent properties of your fixed point of pinching it and the physical stiffnesses of the chain guide the chain to always return to this middle resting position. Whenever you stop swinging the chain like a pendulum, it will always return to the middle as long as you keep your fixed point the same, the way it is intended.
The stiffness of the chain is akin to the joint receptors that are in the capsules, fascia, muscles, etc. of the joint. These receptors tell the brain where the fixed point and influences are for the brain to guide where the middle is.
If you held the fixed point off to the side, the chain would hang a little off to one direction, not ideal for the joint. Pavel Kolar calls it joint centration. Shirley Sahrmann calls it path of instataneous center of rotation. So every joint has a core and it has a neutral that is decided just like a pendulum. It has to know that the stiffness properties allows it to go all the way to the left, right, front, back, etc., so it can rest with no effort in the middle, the position of optimal force transfer.
The clinical application is that the spine’s neutral is a function of full flexion, full extension, full side bending, and full rotation. Then and only then does the core have it’s premiere chance to do as little work as possible for segmental stabilization, and the phasic lumbar muscles can pick up the bracing slack to handle huge loads and force transfers.
If you don’t have yoga-ish mobility, the middle is always off-center, and the local stabilizers (of any joint system) aren’t triggered ideally via the brain getting “wrong” feedback from the joint receptors (Merkel cells, Ruffini nerve endings, Pacinian Corpuscles, etc). Then prime movers have to take over for local stabilization, and there can joint shearing/disruption and a loss of force production in a movement that appears to have global integrity.
It’s why Yogis need to be powerlifters and powerlifters need to be yogis, and yogis need to be powerlifters.
How are you assesing which muscles are out of balance?
The SFMA. The SFMA is more of a global mobility examination. I start there and then break them out, but I actually go backwards. I do the Janda assessment first, which is like 85% of the breakouts, then I stand them and see if they can put it all together.
If the SFMA is right, and there is breathing, then I have some level of confidence that centration is present.