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Old 12-26-2009, 03:34 PM   #99
Erick Mead
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Dojo: Big Green Drum (W. Florida Aikikai)
Location: West Florida
Join Date: Jun 2005
Posts: 2,618
Re: Some similarities in Internal Body Skills between Chinese and Japanese arts

Phi Truong wrote: View Post
how would your model work, for example, with middle of your body where, according to some of the so-called classics of martial arts, your shoulders should align with your hips, i.e. you are not suppose to twist your body to deal with incoming force or to release a force? who know, the classic could be wrong, and that's too a possibility.
If you allow the body to twist, you convert an applied load to a torsional motion -- At that end of that motion then the body reaches its limit of motion and must take up any remaining load in torsional shear stress, but -- and this is the key --without any further reserves of motion or allowable structural stress. You are stuck with whatever structural resistance you have left in relation to the remaining applied load at that point.

If, conversely, the body is maintained to accept the torsional stress -- without the torsional motion -- then the limb/torso acts as a torsion tube. See this diagram

When this torsion is received as stress without initial movement then any element of the tube's surface wants squish in one diagonal stress line (L hand to R foot, for example) and stretch in the other diagonal (R hand to L foot). Look at the stresses on the square element of the torsion tube above, as though it were your torso (good name, huh?)with the stresses extending diagonally along those lines and along the opposing arm and leg. The preferred terminology in this crowd for this aspect seems to be "windings."

Rather than relieve the torsional load stress by allowing the torsional movement, allow this torsional shear (contradictory forces or stress if you prefer that terminology) to develop.
This response gives reserves of both displacement AND allowable stress in your structure so you can apply either or both in succession or combination. Then, in the case of a push -- relieve it by
1) isolating the load in one diagonal (squishing for a push) and then 2) extending back into the source of the load along the "stretchy" diagonal -- as a result the applied torque becomes converted and transferred to the opponent rather than you -- assuming you are properly connected to transfer it -- which is another topic.

The same works in inverse terms in a pull.

What I just described is the equivalent in stress interaction of ikkyo in motion. Just treated stress and motion as equivalent and interchangeable. The point is to imagine correct shapes of the stress and the dynamics.

When Kisshomaru wrote about spherical and spiral motion this is what he spoke of. Spheroidal waves are applicable because, topologically, your body is a deformed version of the actual three-layer sphere it once was.

Technically, what I described was a spheroidal wave S-mode torque conversion. I don't use those terms to sound impressive or to go over your head, but because they have a precise, objective, unambiguous meaning and you can look them up without relying on me or any claim of authority. You can have valid images of action that is occurring in your body in a simplified and yet mechanically correct form. If I am wrong you can call me on it -- in those terms -- which are just as available to you as to me -- with only a very little study.

S-mode waves involve radial and horizontal displacements/stresses like uniform expansion/contraction oscillation -- like a breathing balloon; or oblate/prolate oscillation - (a ball going from squashed sphere to a football and back); T-mode is purely tangential and either torsional or toroidal -- toroidal is harder to envision -- but is a donut wave travelling from pole to pole of the sphere and back, dissipating a the midpoint and concentrating at the extremity -- these relate to fajin.

The two modes also relate to one another, but that's enough for your question.


Erick Mead
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