Posted by: Jack Mankin (MrBatspeed@aol.com) on Tue Sep 30 13:57:38 2008

>>> Jack, I talked to a top scout from the yankees and i explained rotational hitting to him. He understood what i was saying but told me to stay backside dominance. He said to let the backside domanate the front side and it will keep me from flying open and in the end result i will get what i want. Can you explain to me what that means. >>>

Hi Player

The term “flying open” can be interpreted in different ways. To me, the term would mean the batter’s lead-shoulder rotated open without inducing force at the handle that kept the angular acceleration of the bath-head in sync with shoulder rotation. In other words, his shoulders were more “free-wheeling” than performing work.

However, I am quite sure that is not what the Yankee Scout meant by “flying open.” I would guess that his views would be similar to some of the coaches and scouts here on the West Coast. They still advocate the old linear concept that the lead-side should “stay in-there” and be “cleared out” by the advancement of the back-side – similar to the action you would have throwing a ball side-armed.

Being back-side dominate with a passive lead-side may be correct when throwing a ball where almost all accelerating force is delivered by the back-side through one hand to the ball. But this is not the case with the baseball swing. Unlike a baseball, the bat has two hands that apply force to it. In generating maximum angular acceleration of the bat, one of the main functions of the hands (or forearms) is to apply equal opposing forces at the handle.

These equal-opposing forces supplied through the forearms to the hands are derived mainly from shoulder rotation. – I started to explain all the reasons why throwing the top-hand forward during initiation was counterproductive. That would take pages to explain. For this post, let it suffice to say that since the bat-head is first accelerated rearward, and the top-hand is supplying the rearward force while the bottom-hand is supplying the opposing (forward) force.

The forward pull the bottom-hand applies at the handle does not come from the muscles of the lead-arm. The pull of the bottom-hand comes from the rotation of the lead-shoulder with the arm serving mainly as linkage. Therefore, being back-side dominant with a passive lead-side would supply only half the force required for maximum acceleration.

And just as important – during initiation, throwing the top-hand forward (as opposed to applying a rearward force) causes both hands to apply force in the same (rather than opposing) direction. This greatly reduces the rearward acceleration of the bat during initiation.

Jack Mankin