Posted by: Jack Mankin (MrBatspeed@aol.com) on Tue Dec 7 12:35:57 2010

>>> Hi Jack, i read your previous post on wrist snap (circa 2002). I don't fully understand what you meant by flex or unflex of the wrist?

Could you possibly elaborate? I really don't teach my boys (10 & 12) to torque lead (lower hand)or back (top hand) just before contact. Do you teach this method?

Enjoy your site, many thanks. <<<

Hi John

Sorry for the flex/un-flex confusion. Some may refer to it as the "cocking & un-cocking" of the wrist. I use the term flexing (or bending) because much of the bending of the wrist in a linear hand-path occurs from the inertia of the bat. As the knob is driven forward, the bat-head is left trailing behind forcing the wrist to flex (or bend). With rotational mechanics (a CHP & Torque), the angular acceleration of the bat-head keeps pace with the advancement of the knob allowing the wrists remain fairly un-bent.

You ask, "I really don't teach my boys (10 & 12) to torque lead (lower hand)or back (top hand) just before contact. Do you teach this method?" -- Most definitely, in fact, I think I can safely claim my Rotational Model was the first Swing Model to explain and define torque applied at the handle (BHT & THT).

Torque applied at the handle approaching contact (BHT) is a major factor in generating bat speed and therefore the ball's exit speed. Torque can be defined as, "Forces applied from opposing directions that causes an object to rotate about a point." -- In the baseball swing, that point is between the hands.

John, I think a good why to explain handle torque (BHT) approaching contact is with the '4-prong tire wrench' analogy. -- Assume you are using a 4-prong tire wrench to turn a nut on a tire lying on the ground. To apply maximum torque, your left-hand would need to pull back with the equal force your right-hand is being driving forward. Allowing both hands to extend forward would produce no turning force. Or, just driving your right hand forward would only produce limited torque.

The same is true when swinging a bat. For the bat to attain maximum acceleration approaching contact, the batter's lead-hand must be pulling rearward at the same rate his right hand is extending forward. Below are couple video clips discussing the pulling back of the lead-hand.

Burrell & Bonds - BHT mechanics

In this clip, the batter on the left hit the ball about 450 feet while the batter on the right when about 325 feet.

Good & Poor -- BHT

Jack Mankin