Posted by: Jack Mankin (MrBatspeed@aol.com) on Sun Aug 13 18:33:17 2000

>>>I have been studying the rotation swing, and trying to master it. But everytime I execute it, it feels like my arms are lagging behind. I'm thinking that maybe this is the result of letting my arms relax throughout the entire swing, but I'd like to know your thoughts... Thanks for the help, you're doing a terrific job Jack!<<<

Hi Joe

Joe, rotational mechanics allow the arms to stay much more relaxed than with extension type mechanics. But this does not mean they do not have an important role in generating bat speed. --- It is the rotation of the body, not the arms, that accelerates the hands. The arms are used to apply torque to the bat. Torque causes the bat to rotate about a point between the two hands. It's the combination of torque and a circular hand-path that keeps the bat-head from lagging.

**** You can not efficiently apply torque while thrusting the top hand forward. **** Body rotation will pull the bottom hand around toward the pitcher. To apply torque, the top hand must pull back toward the catcher. --- Shoving both hands forward will only accelerate the bat length-wise (knob first).

Below is a post regarding problems I find while doing video reviews.
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"The most common problem I'm finding with those who are learning rotational mechanics is with their transfer mechanics. They may rotate around a fairly good stationary axis, but that rotation is not converted into a corresponding rate of bat-head acceleration (angular displacement). -- When the shoulders have fully rotated (chest facing the pitcher) and the lead shoulder makes that final little pull back toward the catcher, the bat should be accelerated all the way to contact (bat perpendicular to the balls flight). ---See slide show in "Wrist action or torque." --- But when the transfer mechanics are not correct, the bat can still be 50+ degrees from contact when the shoulders have completed their rotation. The batter then must extend the top hand to bring the bat-head to contact. This results in a much longer swing with less bat speed being generated.

Setting top-hand-torque aside for the time being, the two main problems with their mechanics is loose "linkage" and to little bottom-hand torque being applied. When the lead arm and hand have good "linkage" with the knob end of the bat, any rotation of the lead shoulder will cause a strong pulling action (around toward the pitcher) on the knob end of the bat (great for applying torque). But if the hands are to far away from the body or the lead elbow is to flexed (bent), there is to much slop or loose "linkage" and the shoulders may rotate 30 to 50 degrees while applying little pull to the knob end of the bat.

But Tom, great lower body mechanics, the kinetic chain, powerful shoulder rotation, excellent linkage and hours and hours of practice will only lead to mediocrity - if the top hand is driven forward at initiation."
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Jack Mankin