Posted by: tom.guerry (tom.guerry@kp.org) on Sun Sep 7 18:16:46 2003

l
> Hi Tom
>
> Would you not agree that the ultimate objective of good swing
mechanics is to accelerate the bat-head into a predictable plane
at maximum velocity? Whether a mechanic is referred to as Top-
Hand-Torque or Scap Loading, I believe describing the impact
the mechanic has on the plane of the swing and bat-head
acceleration, to be of utmost importance. Yet, I can find little
reference to either in Paul Nyman’s or your discussions on Scap
Loading. In fact, I find the bat itself seldom mentioned in the past
few discussions.
>
> Since I do not have access to Paul’s Private Discussion Board,
it would be most helpful if you clarify a point for me. – Does the
mechanic Paul refers to as “Scap Loading” produce a different
swing plane and bat-head acceleration than the mechanic I
termed in 1991 as “Top-Hand-Torque?”
>
> Jack Mankin
>

Jack-

Thanks for the follow-up question.

My thinking is that how the bat moves through space is very
important,but so is how the muscles are used to do it.Ideally,the
mechaniics need to minimize timing error.This means a short
swing with as rapid acceleration as possible and with as big a
contact area as possible with the bat angle such that solid
contact produces a fair ball.

The bat must swing out ans stay in the power plane of the body
roughly perpendicular to the upper spine.Bend at waist and to
some degree how much the axis leans back or foward are the
main adjusters of the swing plane/disc.I agree that the bat
should be in this plane and swing backward so it makes
contact on the upswing and close in,not way out front.Ideally the
bat tip is as far "out'"(toward opposite batter's box/on axis
perpendicular to flight of ball) as it gets at contact and contact is
at center of percussion.

My interpretation of Nyman is that he considers the overall action
of the rotational swing "whipping".I believe Paul dislikes the THT
concept almost as intensely as "counter-rotation" or circle up to
high cock".In general he sees these as "cues" that are not
adequately reflective of reality.

I am a layperson and not a scientist,but the THT concept works
for me.I think THT is the turning of the bat between the hands as
the bat cocks and uncocks.I think the cocking and uncocking and
"centering of the bat" are all desirable features/cues. I prefer a
somewhat vertical bat (like Bonds).The bat cocks toward the
opposite batters box As he bends at the waist,then starts around
toward the pitcher as he internally rotates the back arm as the
hip cocks,then around more as he scap loads.During scap
loadinf is where the torso can be seen to "counter rotate a
little.Then the back arm begins down to the slot lead by external
rotation of the back arm as the lead leg externally
rotates.Masters of these skills exhibit what Nyman describes as
many degrees of freedom which is discrete automatic control
over the muscles as to moving many muscles locked together
rigidly as the beginner must.With lots of degrees of freedom,for
example,the player can externally rotate the front leg quite open
as they "stride to balance at toe touch" without yet "uncocking the
hip".This gives their motion a smoothness,fliudity and control
that enlarges the timing window for the swing while providing
great power and low timing error.

Soon after the back arm starts down into the slot with external
rotation,the lead arm internally rotates as it prepares for tight
connection and this action accelerates turning of the bat by
torque before launch,which I believe is what you refer to as
"prelaunch" THT.I suspect a mechanics/physics/biomechanics/
physiology principle of some kind is at work here which is what
you explained in the past(Jack speed gains thread with Zig from
March of this year):

"Efficient transfer mechanics produce the dynamic load
(exponential resistant factor) that causes the “deceleration” of
segments you mentioned. Poor transfer mechanics offers a
much-reduced resistance (load or work done) to segment
rotation and therefore, covert less rotation energy into bat
speed."

I don't believe Nyman thinks of this as torque.It feels like torque
to me because it is arm action turning the bat between the 2
hands,

Next,there is THT at launch which creates acceleration by the
addition of lead arm pull as the front soide connection is made.

I think it is necessary to teach some bat cock/uncock (bart's
idea?)and how to use the big muscles to create this motion with
good timing.The THT description doesn't work for me as a
teaching verbal"cue" nor do desriptions of finger pressure/
direction of force with hands.Furthermore when I look at super
slowmo of the hands during bat cock/uncock/prelauncnch and
launch tht,I see the top hand staying back against the back
shoulder(in behind head as you describe it) as it continues to
load while the bottom hand works the knob around it as the bat
gets into the swing plane.

To a layperson like me,