Posted by: Jack Mankin (MrBatspeed@aol.com) on Tue Nov 2 12:50:45 2004

Hi JJA

You stated the following.

>>> 1. If differential forces on the bat are important, this would imply that the distance between the forces would be important for generating torque (like you corrected my mistake above). This is a basic physics fact. This would thus further imply that a Cobb/Wagner like split-grip, with more lever arm between the hands, would imply more torque on the bat and hence more batspeed. Since I think all of us would agree this is not the case, this leads to a contradication, and implies differential forces are not important. <<<

I must disagree with your contention that increasing the lever arm (hands wider apart) should increase bat speed if torque is a major factor of generating angular displacement. Increasing the lever arm would increase the leverage but not the maximum bat speed that could be attained. As an example - surely you would agree that torque applied to the rear wheel of a bike is a major factor for its acceleration. Would you also agree that although a biker may choose a larger sprocket (increased lever arm) for climbing hills, he certainly would not increase the sprocket size to attain maximum speed.

Likewise, taking a wider grip would increase leverage to accelerate a more static bat over a shorter distance. However, if torque is being applied around the entire swing plane (THT thru BHT), the batter will generate greater bat speed with the hands together (smaller lever arm). A wide grip also restricts the development of a CHP and therefore, the transfer of the body's rotational energy into bat speed. It is the ability of a great hitter to maintain a CHP while applying torque that sets him apart from those just learning to apply THT and BHT. -- This will be an important point in our discussion below of the one-hand vs two-hand bat speeds.


>>> 2. Consider a modified one arm swing. Grip the bat normally with the bottom hand, but use an open top hand grip, with the bat resting in the palm and between the thumb and forefinger on the bat. This open top hand allows the bat to be supported but not allow significant forces to be transmitted to the bat. Even simpler would be a one arm swing, but this way allows the bat to be supported and thus easier to swing.

This grip setup makes it virtually impossible to impart "top hand torqe" or "bottom hand torque". Yet go ahead and swing the bat. I would argue that even a novice could generate in excess of 80% of their normal batspeed with this technique. I can, and I'm certainly no John Elliot. <<<

I have conducted many tests to determine the bat speed attained with one hand from different hand-path lengths and rates of displacement. I will be glad to discuss the data I obtained with you. But first, it would be helpful for the discussion if we clarify your position on what constitutes the "whip effect" or "flailing action" that accelerates the bat (one or two handed). --- Is it your position that a "whip effect" or "flailing action" occurs with linear (or straight) extension and slowdown of the hands? In other words, if a bat was accelerated from a linear force applied at a single point (zero lever arm - no torque), there is no "whip effect" or "flailing action" acting on the bat-head during the acceleration of the single point or when it came to a stop? --- JJA, I think this gets to the heart of our differences on the Adair model and our future discussion of the one-hand vs two-hand bat speeds.

Jack Mankin