Posted by: Jack Mankin (MrBatspeed@aol.com) on Sun Oct 24 14:20:58 2004

>>> By your message, 'bow arch' becomes clear gradually.

I guess typical 'bow arch' is old type rotational method. Hitters are Williams, Dimaggio, Mantle and so on.
Extension of front leg and backward movement of front shoulder occur, and generated energy is transferred through the bottom hand to the bat.
(bottom hand flail)
Mantle's form can be seen here.
http://www.youthbaseballcoaching.com/swing.html

Two types which I mentioned in the message Oct 18 are different from 'bow arch'.
It may be said that typeA is 'arch bow arch' and typeB is 'arch bow'.

Bonds is typeA and Garciaparra is typeB
http://www.geocities.jp/tokyomarlin/bonds3pics.jpg
http://www.geocities.jp/tokyomarlin/garciaparra3pics.jpg

Both types pull the bat with top hand using abs. Therefore 'bow' occurs.
Because Bonds pull the bat backward with top hand before contact, 'arch' is added. The barrel of the bat is accelerated by forward movement of center of gravity of the bat and backward force applied by top hand.(top hand flail). It's like whip or fly fishing and not push-pull torque. <<<

Hi Marlin, RQL, Tom and all.

I thank you all for your input on “bow-arch”, “flail” and our earlier discussions on “scap loading”. It appears to me that Paul and I possibly agree on the important principles of the baseball swing. Basically, it sounds like we are describing the same mechanics using different terminology. I define mechanics by the forces that are applied at the handle to accelerate the bat-head. Paul’s terms concentrate more on muscles and body structure that supply those forces.

Findings from my study of the baseball swing (late 1980’s & early 1990’s) concluded there were substantial differences between the mechanics exhibited by the top hitters and the mechanics being taught at all levels.

(1) Teaching of the baseball swing was based on the theory that the energy for the swing came from the forward movement of the body (Ted Williams being the lone dissenter at that time). --- My findings showed that the great hitters developed their energy from “Rotation around a stationary axis.”
(2) Batters were taught to drive the knob of the bat back toward the pitcher by extending the top-hand. --- My study showed that top-hand of the best hitters was actually being ‘pulled back’ toward the catcher at the start of the swing.
(3) Batters were taught to extend their hands in a straight line (A to B) toward the pitcher (or ball). --- My study showed that the mechanics of the top hitters produced a “Circular Hand-Path.”
(4) Batters were taught to cast their weight upon a firm front leg and extend the bottom-hand toward the ball. --- My findings showed that in the swing of the great hitters the rotation of the shoulders, the extension of the lead-leg and the “un-shrugging” of the lead-shoulder was actually pulling the bottom-hand back toward the catcher at contact.

Note: I might add that I could find NO ONE (in the field or discussion boards) that agreed with the above findings until years later.

At that time, I had little understanding of exactly how these batting mechanics generated bat-head acceleration. Therefore, over the next couple of years, I took the information I had gathered to a number of Physics Labs. They all agreed that there are two forces at work in the baseball swing that induce angular displacement of the bat.

(1) The body’s rotational energy is transferred into the angular displacement of the bat by the angular displacement of the hand-path
(2) The second force that generates angular bat displacement is “torque” induced from the hands applying force at the handle from opposing directions.

I then used these findings to form my model for “Rotational Transfer Mechanics.” The four corner stones are: (1) Rotation around a stationary axis. (2) THT – top-hand applying torque at initiation. (3) The CHP – circular hand-path. (4) BHT – bottom-hand applying torque at contact.

As I stated earlier, it is my opinion that Paul and I possibly agree on the important principles of the baseball swing. He concentrates more on the muscles and body structure to define his terms.

(1) Rotation around a stationary axis --- Basically, I think Paul agrees but feels there may also be a forward component.
(2) THT --- Since he does not think torque is a factor in generating bat speed, he refers to the pulling back of the top-hand as “scap loading.”
(3) CHP --- I think he refers to the angular displacement of the bat from the CHP as a “flailing” action.
(4) BHT --- It is my opinion that Paul uses the term “bow-arch” to identify the body movement that pulls the bottom-hand back at contact.

I have no problem with coaches using those terms they feel most comfortable with. However, this site has defined the terms by the forces a mechanic applies to the bat – not the muscles that supplied the forces. Therefore, our readers will better understand your post if you use our terms. If you choose to use other terms, make sure you clearly define them.

Jack Mankin