Posted by: Jack Mankin (Mrbatspeed@aol.com) on Wed Apr 23 21:08:35 2003

>>> Dear Jack,
I have some questions I would like to ask you. First of all, wouldn't opening the top half and closing the bottom half really "yank the hands through," and get "the hips ahead of the hands?" I found it does.

Secondly, are not the hips initiated by dropping the front heel (just a clarification)?

Finally, doesn't proper hip rotation demand that you start with you weight slightly forward, then dip the back shoulder, tuck the back elbow HARD, and keep the bat close to the body while you turn your back palm "up." This puts the weight against the back thigh and forces faster rotation.

To rephrase, does not tucking the bat in tight to the body (i.e., a lag position) accelerate the bat, since one can rotate faster when his or her "limbs," including the "bat," is brought in close to the body? Doesn't initiating CHP from the beginning produce a "parachuting effect" counterproductive to hip rotation?

I do not think the swing as loose and tension-free. I'm counting on you to prove / disprove me as you did in the past.

Sincerely,
BHL (Geoff)
Knight1285@aol.com <<<

Hi BHL (Geoff)

(1) “I have some questions I would like to ask you. First of all, wouldn't opening the top half and closing the bottom half really "yank the hands through," and get "the hips ahead of the hands?" I found it does.”

I am sorry, BHL, but I am a little confused with your question. My understanding of what you are saying is that if a batter opens or rotates the shoulders (top half) while keeping the hips (bottom half) closed, it would really “yank the hands through," and get "the hips ahead of the hands?" But that would have the shoulders and hands rotating ahead of the hips. So I must be misreading your question. Please help me with this one.

##

(2) “Secondly, are not the hips initiated by dropping the front heel (just a clarification)?”

Yes, I think it is safe to say that rotation can be initiated by lowering the front heel.

##

(3) “Finally, doesn't proper hip rotation demand that you start with you weight slightly forward, then dip the back shoulder, tuck the back elbow HARD, and keep the bat close to the body while you turn your back palm "up." This puts the weight against the back thigh and forces faster rotation.

To rephrase, does not tucking the bat in tight to the body (i.e., a lag position) accelerate the bat, since one can rotate faster when his or her "limbs," including the "bat," is brought in close to the body? Doesn't initiating CHP from the beginning produce a "parachuting effect" counterproductive to hip rotation?

I do not think the swing as loose and tension-free. I'm counting on you to prove / disprove me as you did in the past.”

Maybe the best way I can address your statement is by analyzing why a Figure Skater brings the arms in close or extends them out wide during a spin. --- After the skater initiates the forces to induce the spin, he/she will start bringing the hands and arms in closer to the body. The closer the skater brings the hand/arms in, the lower their velocity and therefore the less the load to rotational momentum (less work being done), and therefore the faster the skater will spin. In order to slow or stop the spin, the skater increases the load to rotational momentum by widening the path of the hands and arms. The wider the path, the greater their velocity and the greater the drain on rotational momentum. The body’s rate of spin approaches zero as rotational momentum approaches zero.

The same basic principles of rotation apply to the baseball swing, except that in the baseball swing the batter’s legs and torso are constantly supplying rotational energy throughout the swing. Keeping the bat’s knob in close and extending out in a straight-line produces a relatively small load to rotation (little work being done). So the batter can rotate quickly but little rotational energy is transferred to accelerate the angular displacement of the bat-head (bat speed). The bat-head lags behind the hands deep into the swing and is brought to contact mainly from the extension of the backhand (torque).

A hand-path with angular displacement (circular-hand-path) which induces an angular displacement of the bat-head offers a greater load to rotation. The wider the hand-path, the greater the load to rotation. (BHL, I think you referred to this increasing load as the "parachuting effect”.) Within certain limits, this greater load to rotation means more work is being done and therefore more of the body’s rotational energy is being transferred into bat speed. This principle (CHP) generates about 50% of a good hitter’s bat speed (the balance from torque). This means the great hitters need not rely as heavily on torque to accelerate the bat-head as does a hitter with more linear mechanics.

Jack Mankin