Posted by: FiveFrameSwing (lyons.chris@yahoo.com) on Wed Nov 26 13:10:53 2008

> I would like to get your thoughts on a linear negative move. In looking at a number of the college softball players, their negative move is a weight-shift back towards the catcher and then the stride and then into rotation. I know in your videos you demonstrate a counter-rotation of about 30 degrees for the load (negative move). Just curious as to your thoughts on this more linear type of load?
>
> Hi Ken
>
> The reason for the 30-degree “inward turn” is to rotate the hands back to good position to create a productive CHP. I think you will find that most coaches that promotes “you must go back to go forward” or “walk away from the hands” have also bought into the “Crack of the Whip” theory for generating bat speed. This theory contends that the energy from a forward weight shift and straight extension of the hands causes the bat to snap around like the cracking a whip.
>
> The problem is, this is a false theory. There is no angular acceleration of the bat-head that results from weight shift and a straight extension of the hands. Therefore, all the linear cues based on the theory are misleading. This illustrates why I find most discussions on swing mechanics to be pointless unless both participants first agree on what forces are actually responsible for inducing bat speed. Once those forces are agreed upon, then a constructive discussion of the swing mechanics that most efficiently produces those forces can occur.
>
> I cover to forces acting on the bat that induces its angular acceleration rate at
> <a href="http://www.batspeed.com/research10.html">Mechanics that Generate Bat Speed</a>
> If anyone feels there are forces, other than those described, that induces bat speed, I would be glad to discuss them with you.
>
> Jack Mankin


Jack,

I’m not sure I’m understanding your comments about the cues "you must go back to go forward" and "walk away from the hands". In my opinion having the hands move back towards the catcher during the forward stride has multiple benefits, one of which is obtaining early lead arm extension and the promotion of a semi-circular hand path.

Are you advocating a 30-degree inward turn as opposed to obtaining early lead arm extension?

-- FFS