Posted by: Teacherman () on Sun Jan 27 15:09:44 2008

Then there is camp $4.

The REAL camp.

Hip rotation starts as the hitter's coil turns to uncoil. No pause between. He's riding his back leg at that point and carrying momentum forward. There is a linear component to this momentum. But it is mostly rotational. He is not shifting weight at this point.

The hip rotation is around the rear hip ball and socket joint. It is induced by the muscles of the rear leg and rear hip socket. I suppose the lower torso/hip muscles are involved also. The opening of the front leg also helps. It continues as a running start....not aggressive at this point......just creating momentum and creating stretch between the upper and lower halves. The front foot is still in the air for most of this. And a load is maintained in the rear hip ball and socket joint as this occurs.

Then.....at "go".....after the hips have offset...where the hitter's provate parts can be seen by the pitcher....the hitter unloads the rear hip joint with a push against the ground and a push in and against that rear hip joint....forcing both weight shift and rotation. This forces the weight forward which is caught by the front leg which then provides a lever which firms up making sure there is no drift forward, which would bleed rotational energy from the system. The front leg is NOT a source of rotation. It is not an engine firing sending the front hip rearward. It is simply a lever that creates a pivot point for the hips to keep them from drifting forward. IN THAT SENSE....the front leg does help turn linear momentum into rotational momentum....by simply offering the lever to rotate against. It does not act as an engine of rotation.

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Verify what I've written by looking at this clip.

http://www.teachersbilliards.com/Bondsoverhead.gif