Posted by: dougdinger () on Fri Apr 9 21:10:38 2004

>>> Jack, I need something clarified. When you mean "apply THT at initiation of swing" I know you mean that you use your top hand to apply a rotational force to the bat and blah blah, you are "using" your top hand. Right? So what do you do with the bottom hand at initiation. BHT? Do you "use" the bottom hand in any way, or do you just let it do its own thing and only "use" the top hand at initiation. My understanding so far has been that if proper THT is applied at beginning, than BHT will come in by itself before contact. I think you said so, a long long time ago in an old thread. But I'm not exactly sure. <<<
>
> During initiation, the bottom-hand stays at the back-shoulder and serves more as a pivot point for the back-arm to pull the top-hand (and bat-head) around. But it is important to note that as the top-hand is being pulled back toward the catcher, shoulder rotation is pulling the bottom-hand (and knob) around toward the pitcher.
>
> The top-hand pulling back not only accelerates the bat-head into the swing plane by applying torque to the bat, it also helps keep the lead-arm connected with body rotation to generate a productive circular hand-path. And Dougdinger, you remember correctly. --- "A ballistic motion, once initiated, produces trajectories that can only be efficiently changed at its margins." – This is an important bio-mechanical principle.
>
> For pitches from the middle-in, when a batter correctly applies THT and CHP at initiation, the bat-head trajectories will stay is sync with shoulder rotation trajectories. Therefore, the lead-shoulder will have rotated to the point where the bottom-hand is being pulling back toward the catcher (105 degree position) generating BHT to accelerate the bat to contact.
>
> Jack Mankin
>
>
> Clear.