Posted by: Jack Mankin (MrBatspeed@aol.com) on Thu Dec 16 18:09:43 1999

Hi All

There has been a lot of discussion lately on weight shift and its relationship to bat speed. It might be helpful if I gave my thoughts concerning that relationship and momentum. --- I have nothing against a batter taking a short stride (or step) in preparation for the swing. For those who have been using it for some time, a step may be necessary to set up the swings timing sequence. But I am concerned about some coaches thinking regarding the effect that weight shift (or momentum) has on the swing itself.

As the batter strides in preparation for the swing there will be forward movement (linear) of the body. And yes, there will be weight shifted (and momentum developed) forward as this occurs. The batter then plants the front foot and applies pressure with the front leg to slow down forward movement. Before the batter initiates the swing (body rotates & hands start moving) all forward (linear) movement of the body has ceased. --- His center of mass is at rest. --- When he initiates the swing, he will rotate around a stationary axis.

Gentleman, all moving objects have momentum. But you can’t store-up momentum to be used after a body comes to rest. Once a moving object comes to a stop its momentum (or weight shift) has been expended. The same is true for a batter --- The energy developed during weight shift is expended before the swing starts.

Jack Mankin