Posted by: Jack Mankin (MrBatspeed@aol.com) on Sun Apr 16 18:38:46 2006

>>> Jack-

I think motionanalysius would be good at getting at this with the perspective that mechanics are much as you describe them with certain predictable variation that goes along with pitch location.

Certainly we want to see the seqeuntial acceleration/deceleration of segments with associated migration of the swing axis and the "sped gains" seen with Zig's equipment for example.

I would think that in the case of inside/high ball the head would come more forward to set axis and shoulders would turn more with central axis. Outside/low ball, head stays back and swing might have more off center axis. Field studies might be good to sort this out. <<<

Hi Tom

I would agree that using a Motion Study Computer would give more exact data. But not having one presently available, I went to the swing clips at http://www.youthbaseballcoaching.com/swings.html. I framed forward to initiation (shoulders starting to rotate) and placed a card at the nose of each hitter that showed an across-the-plate view. I then framed each clip forward to contact.

As I stated earlier, “If the back-shoulder were to rotate around a blocked lead-shoulder (like a gate swinging), then the spine, neck and head must also swing around and forward.”

I am not sure of pitch location, but not one of the following swing clips showed the head move forward during rotation. . - Bagwell – Boone – Bonds – Jones – Giambi – Glauss – Griffey – Guerrero – Gonzalez – McGwire – Palmeiro – Renteria – Snow – Soriano – Sosa – Tejada – Thomas – Walker – . This means these hitters' shoulders are rotating (or “spinning”) about the center of their body.

Note even Frank Thomas, the hitter that linear enthusiasts point to, does not move his head forward during the swing. The only clip I could find that would better fit the “swinging like a gate” analogy was the clip of Bernie Williams.

Jack Mankin