Posted by: Jimmy () on Sat Jan 6 15:52:56 2007

> Hi All
>
> Jimmy gave us his analysis of the Sosa clip (http://www.youthbaseballcoaching.com/
mpg/sosa_sammy2.mpeg ) from his linear perspective (extension of the back-arm
accelerates the bat-head). Now, I will present my analysis of the clip from a rotational
transfer perspective.
>
> Jimmy stated; “Through the point of contact the bottom hand is more a fulcrum for the
top hand to apply leverage to the bat. If the front shoulder was intentionaly pulled back
towards the catcher to increase bottom hand torque, the top hand would lose force and
drive on the bat. In the Sosa (middle-in) clip, if you click back and forth between the
frames of contact and just before contact, you will see that the most action is comming
from his top hand and the barrel.”
>
> Let us do as Jimmy asked and advance the frames forward to the frame just before
contact (knob of the can be seen just above the catchers mitt). Note the position of the
back-elbow at Sosa’s side. Now advance to the next frame (bat at or just before contact).
Note that the elbow did not extend. It is still in the “L” position at his side as the bat
arrives at contact.
>
> Does the elbow remaining back in the “L” position mean the top-hand is not applying a
foreword force to the handle? No, it is exerting a powerful forward force. However, it is
being driven forward from shoulder rotation rather than the extension of the arm. This is a
far more powerful force because it is being driven from the large muscles of the legs and
torso rather than the smaller muscles of the arm. – Ask yourself, had you rather be hit with
a boxer’s “hook” (arm remaining in the “L” position), or, from his “jab”(arm extending)?
>
> Now, advance forward to the next frame (ball leaving the bat). – The ball is only in
contact with the bat for 1/2000 second. During that time, the bat only moves forward
about 5/8 to ¾ inch. Once the ball exits the bat, any further force applied to the bat has
no impact on the ball’s flight. – Note that the extension of Sosa’s arm occurred after the
ball was no its way.
>
> Now, let us take a look the lead-shoulder rotation Jimmy discounts. -- Return to the
frame just before the knob arrives at the catcher’s mitt (2 frames from contact). Note the
rearward rotation of the lead-shoulder in the next 2 frames. Note that this rearward
rotation of the lead-shoulder exerts a strong pull (through the bottom-hand) on the knob
end of the bat.
>
> We now have back-shoulder rotation driving the top-hand forward as the rearward
rotation of the lead-shoulder pulls the knob rearward. That is how maximum torque
(forces exerted from opposing directions) is applied. – In order to generate maximum bat
speed, a batter’s mechanics must make maximum use of the body’s larger muscle groups
of the legs and torso.
>
> Jack Mankin

Jack,

You forgot to mention that if Sosa tries to feel something totally opposite than what you're
discribing.

Jimmy