Posted by: tom.guerry (tom.guerry@kp.org) on Wed Nov 24 09:43:03 2004

grc-

I think the main "accelerator" is what Jack calls the "rotational component" which is the momentum generation and transfer via ball on string type mechanics dependent on the "CHP".

Golf and hitting are very similar in this respect,however,if you take the time to perform Jack's "7 iron drill" you will feel how different the golf swing is from hitting rotationally.This is a case where the swing is greatly quickened by more acceleration over a shorter path to "escape velocity" by the application of torque with what would be called the "top hand" in hitting (bottom hand in golf) at the top of the golf swing.This short fast swing is great for hitting (minimize timing error),not for golf (too much spatial error).

I think this "torque application" must also be an important factor in "amplifying" acceleration characteristics to optimize swing mechanics for hitting.The crucial time to apply this,analagous to when the club starts down in golf is around "initiation" which might include "pre-launch" THT and "THT at launch".In hitting,this action is still part of the loading action (body still coiling/generating momentum that will energize torso to drive bat,torso momentum maxing out a frame or 2 after front heel gets down).It is very similar to the loading action of the throwing arm for a good "rotational"/power overhand throw.

So now we have talked about "CHP" and "THT".

A further revision/adaptation of the hitting/rotational swing is the handpath hook that Jack calls "BHT".To me this seems like a whipping type action,not true application of torque to handle,but rather an enhanced acceleration of the bat due to the hooking shape of the handpath on the approach controlled mainly by the front side.Nyman's simulation shows only "reactive torque" which is extremely non-intuitive.

So bulk of acceleration comes from momentum transfer,but this may be greatly enhanced at initiation as can be felt in the golf club drill by applying torque to the handle of the club/bat which I suggest can BOTH accentuate efficiency of coil by assisting in creating last quick bit of coil ("xfactor stretch") and by preparing bat to fire out to extension quicker once torso gets to max momentum.It is alos necessary to get the proper "swing plane" set upi because the bat needs to accelerate in the 2 dimensional "power plane".

Nyman has computer simulations at hitting-mechanics .org that simulate "CHP"/double pendulum/2-segment whip type mechanics as well as effect of handpath hook.Nothing there that would assess "THT effect at initiation".This might require setting up a good CHP/HOOK model,then comparing this to actual hitters who may be further optimizing the swing with torque application at the handle before/at initiation/launch to see how the swings differ from the model.