Posted by: Jack Mankin (MrBatspeed@aol.com) on Wed Oct 31 15:12:36 2007

Hi All

In a thread below (Fastpitch hitting -- Linear vs Rotational), Teacherman, Tom and I discussed our differences of how energy is transferred in the swing. Our main difference centers of the role of hip and shoulder rotation.

To further the discussion, I promised to show clips of MLB hitters and let you, the reader, decide for yourself which of our positions on the topic is verified by what the batter’s mechanics exhibits. But first, here is a brief summery of our positions.

My Position
We all agree that rotating the hips is an important factor in generating energy for the swing. However, I have always maintained that since the arms/wrists/hands/bat segmentation is linked at the shoulders rather than at the hips, the importance of hip rotation is its contribution to shoulder rotation. Therefore, it is the rotation of the shoulders (not the hips) that transferees the body’s rotational energy to the bat.

Teacherman’s Position
He contends that shoulder rotation does not transfer the energy. He believes shoulder rotation is to slow and would produce “bat drag.” Therefore, he believes shoulder rotation must be restricted and the energy of hip rotation “bypasses” the shoulders to the forearms. (How it made the jump – he never explained)

He further states:
(A) “You see....the hips rotate. The shoulders do not.”
(B) “Shoulder rotation occuring at the same time as hip rotation simply can not and does not work.

Tom’s Position
He agrees with Teacherman that shoulder rotation does not transfer the body’s energy and should be restricted. Rather than “shoulder rotation” being the source, Tom (and Teacherman) contends that it is the “tilting of the shoulders” that supplies the power.

(Teacherman’s statement)
“Shoulder rotation occuring at the same time as hip rotation simply can not and does not work.
(Tom’s reply)
>> agree, it is probably not even humanly possible to lock the two together during turning<<

The first clip is an overhead of Pete Rose. I chose this clip because an overhead view is looking down the axis of rotation and offers a better view of the hip-to-shoulder relationship.
Rose hip/shoulder comparison

The second clip is a frontal of Bonds’ hip-to-shoulder rotation.
Bonds hip/shoulder comparison.

The third clip is also a frontal view of Bonds. This is a better view for discussing “shoulder rotation vs tilt.”
Bonds - shoulder tilt or rotation

Jack Mankin