Posted by: Jack Mankin (MrBatspeed@aol.com) on Sat Sep 4 11:12:25 2010

>The main contribution of 'hip rotation' is to induce a stronger 'shoulder rotation'. --- I would like to hear anyone's thoughts that believe energy from 'hip rotation' can effect the bat's acceleration while the shoulders are held static.
>
> Jack Mankin

>>> Hi Jack

The reason why hip rotation is so important is that without it the shoulders will rotate slower and cause slower bat speeds. If the small muscles of the shoulders and arms are forced to pull the big muscles of the legs and hips due to them rotating ahead of the hips the arms must be going slower.

Therefore without hip rotation the rotation of the shoulders are not as effiecent and will not only reduce speed but also reduce the length that the bat will travel on the same plane with the ball. This will reduce the area that a bat and ball can collide and create mishits and poor contact (over or under the ball).

Since the lower body, primarly the legs, start and accelerate the hip rotation the first motion to create the best shoulder rotation are the legs. Which allows the hips to rotate, which allows the torso to rotate and then allow the shoulders to rotate freely without having to work against the bigger muscles that support the shoulders and eventuately the arms.

All parts are linked together so if a link is broken anywhere along the chain the movement is not effiecent. Like most machines larger pieces of equipment move smaller pieces of equipment faster then the other way around. <<<

Hi Dave

I see no conflict between your analysis of the importance of hip rotation and my statement that "The main contribution of 'hip rotation' is to induce a stronger 'shoulder rotation'"

The point of my post supports your statement that "All parts are linked together so if a link is broken anywhere along the chain the movement is not effiecent." -- The shoulders are a key link in the chain you refer to. Not allowing the shoulders to rotate breaks the linkage between the rotating hips and the bat. This is why I stated that it is bio-mechanically impossible for the rotational energy generated by the lower body to be transferred to the bat if the shoulders remain static.

** Once again, if anyone can explain a bio-mechanical principle that allows the energy of hip rotation to by-pass the shoulders and reach the bat -- I would appreciate your thoughts.

Jack Mankin