Mike Sigman wrote:
Well, I can do it. *Sometimes* I add certain rotational movements, but they are more cam-like than "rotational"; and they simply represent additional aspects to the whole of the power chain.
A point I missed. The major torso joints, shoulder, hip, are universal joints. No cam action of these joints is possible because an out of plane input will alter the plane of movement of the joint without much reaction. Which is sort of my point,
The spine can store energy, but is an exceedingly weak lever - a fact for which countless chiropractors are immensely graterful and their patients proportionally saddened. It is, however, a marvelously stayed segmental column, with lots of little offset cam-like processes, that are "guywired" in opposing sets to the remaining superstructure (chest/ribs armature, shoulder girdle and hip girdle).
The spine is remarakbly poowerful in torque however. It can rotate about its vertical axis nearly 270 degrees. By setting a maximum tension potentional on one side of each tension pair one can release them, allowing the connective sheath loaded in torsional shear to recoil in a spira time series, and then applying the opposite tension in the same timing to add more inertia, this can be done to maximize the harmonic resonance of the spiral wave of torque converted to rotation -- resulting in a devastating amount of kinetic energy.
Let me now combine the analytic with the (not so) metaphorical and show you what I am reaching for in terms of explanatory power of reference.
These little offset tension cams do a great job of propagating torque energy in a three axis rotation, with one point of support (viz. the chest push video) and releasing it explosively, as any major league catcher will tell you, who wears bogu precisely because of the seriousness of the impact danger.
Are we to assume that a pitcher can linearly push a baseball faster toward the plate than the balletic scheme of rotational transformations that are actually used to do this? (Yet another common ground for the U.S and Japan.) MLB may want to pay MIke hefty consulting fees, if this is so.
If you watch the instant replays or motion analysis (e.g. -- http://www.peavynet.com/video1/Cumberland_Pitch.wmv
) you will see a good pitcher's bent arm tumble in three axes as it comes over (right behind his torso leading with the same three-axis tumble). It comes into an extremely tight radius of turn in the horizontal plane and vertical A/P plane with maximum bend (centripetal constraint) as it passes his center.
The body and arm then uncoil in a three dimensional spiral with (constantly reducing radius) all converging on the point of release thus giving the ball maximum available energy. This process with different application is what I have described in aiki techniques where the energy is going the other way. Muscles function in tension, so the articulation is not as stable going the other way with aiki technique, as it is in pitching the ball.
A pitcher's motion also follows the ikkyo line, not surpisingly. The arm in receiving ikkyo is in inverse postion to the arm in throwing (i.e. -- tenchi). At the end of the throw the pitcher is set up for mae ukemi.
We typically view uke's attacking hand as the throwing arm, maximizing energy for impact. However, an ikkyo may be viewed in this context as converting that attack into a non- throwing arm which I then use to help uke wind up the other way to throw his energy away from me with the other arm.