Posted by: Jack Mankin (MrBatspeed@aol.com) on Tue Jan 22 00:58:52 2008

Hi Tom

What I find most telling in you post is that even in your opening comment, you referred to the subject as, "shoulder tilt" vs "shoulde turn" instead of “shoulder tilt” vs “shoulder rotation.” It occurred to me that I could not recall you using the term “shoulder rotation” in any of your post I have read.

In this post, even though you wrote the subject was to be "shoulder tilt" vs "shoulde turn", you never once mentioned “shoulder turn.” For the balance of your post, you discuss the importance of "spine angle", "spine tilt" and “shoulder tilt.” I agree those are important adjustments to set up the correct launch position and axis for the rotational plane of the shoulders.

I would also agree that while adjusting "spine angle", "spine tilt" and “shoulder tilt,” this may aid in accelerating a cocked forward bat rearward to the launch position. However, from the launch position to contact, "spine angle", "spine tilt" and “shoulder tilt” remain constant and are not a factor in generating bat speed. It is the rotation of the shoulders about that tilted axis that powers the arms/wrists/hands/bat around the swing plane.

With the ground as a reference, rotation around a tilted axis causes the lead-shoulder to rotate to a higher position while the back-shoulder rotates to a lower position. It could be that by “shoulder tilting,” you are saying the same thing. I am not sure. In any case, I find it hard to understand why the term “shoulder rotation” is not mentioned in your analysis of swing mechanics.

Jack Mankin