Posted by: tom.guerry (tom.guerry@kp.org) on Thu Aug 31 08:29:49 2006

Jack, Zig, et al -

I think simultaneous motionanalysis and videoanalysis of clips by the two of you would really clear up any confusion about your positions.

If Zig's motionanalysis shows efficient "speed gains", then the hitter is not "spinning" in the derogatory sense of too much one piece body rotation with power leaks due to wasting energy overrotationg (poorly timed deceleration) of the lower/proximal body parts.

IF there are the expected sequential/segmental speed gains, then there must be deceleration of the hips before contact and turning of the shoulders right up to contact. This may or may not look like a swinging gate or revolving door on surface video appearance.

I think the mechanics Jack describes are the optimal/quick ones which a number of body types seem to be able to execute.

This is a bellyup short swing radius with "BHT" emphasis or "hook" of handpath for inside location. In this case, the body will turn more with more of a revolving door appearance, but not with inefficient speed gains. This can be taken for "suboptimal spinning" if you do not look at other active and reactive motions as a proxy for the presence of efficient speed gains (summation of levers/summation of velocity/kinetic link principle/well timed segmental acceleration/deceleration/whatever you call it).

On the other hand if you sequence the body well for a long swing radius/high load/outside location in an off the plate set up, the apperance of efficient speed gains is more that of a opening gate with torso sucked dry so quickly that the shoulders may nearly stop turning prior to contact.

The surface video appearance of good swing can meet whatever definition you want to give it based on video appearance if you do not take into account that the loads may be different and the axis of rotation migrates as the swing proceeds (as proximal link deceleration occurs).

Likewise the definition of barring may be slightly different so that it could be thought of as a flaw or not, depending on the context.

I hope Batspeed gets video display capability on the website and that ZIg might continue to contribute his motionanalysis expertise in supplying more info about how mechanical effciency and surface visual appearance relate.