Posted by: tom.guerry (tom.guerry@kp.org) on Mon Dec 17 08:25:10 2001

>
> > > > > > >
> > > > > > > Let me know if any of these thoughts are helpful.
> > > > > >
> > > > > > Shall we put these things in plain English? Back to Physiology 101, o.k.?
> > > > > >
> > > > > > On an inside pitch, it is easy enough for both the top and the bottom arms to "reach" the pitch since the shoulder to which both arms are connected to are is moving in that direction.
> > > > > >
> > > > > > On an outside pitch, if the shoulder rotates 90 degrees it is still fairly easy for the hitter to "reach" the outside pitch.
> > > > > >
> > > > > > However, for the same outside pitch, if the shoulder rotates 90 degrees, the bottom (front)arm, being connected to the shoulder will hace rotated AWAY from the outside pitch. Therefore it is the bottom arm that restricts shoulder (and hip) rotation, lest the bat be rotated AWAY from the outside pitch.
> > > > > >
> > > > > > I might also add that even if you were to take a swing one-handed with the bottom arm only, it is physiogically very dificult to rotate the hips/shoulders much more than 45 degrees while trying to reach the outside pitch.In fact, the little rotation there is happens slightly AFTER the arms have started working. as opposed to anside pitch where the hips start turning BEFORE the arms start working.
> > > > > >
> > > > > > Your problem is that you are trying to give invalid scientific explanations to explain something that can quite easily be explained in physiological terms.
> > > > >
> > > > >
> > > > > saat,
> > > > >
> > > > > EXCELLENT points.
> > > > >
> > > > > ray porco
> > > > > >
> > > > > >
> > > > > >
> > > >
> > > > Thanks for responding.Could you clarify what you mean by " arms start working." Thanks again.
> > >
> > > Arms start working, meaning the arms/hands starting the swing slightly ahead of the hips. Yes, I can just hear Mark saying "that sounds linear", but the fact is, there are physiological reasons as to why you can't effectively use full hip & shoulder rotation to hit a ball that is away from you rather than in front of you.
> >
> > Saat-
> >
> > I would be interested in hearing more details about the hand/arm action,if you think that's important.If not just ignore this.Remember,the world of analysis(this fun detailed stuff)is different from the world of "just doing it",but a coach has to have some analytic process(maybe not this compulsive without certain character disorders.)
> >
> > I do think early hand/arm action is important based on my interpretation of Jack's work which is probably a little different from what Jack intends and a lot different from what many others may be thinking.
> >
> > First,I think in any case you need separation of the upper and lower body to prepare for power generation.I like Epstein's cue of "hips lead the hands" as a universal.I think this is a more popular "cue" than "hips lead the torso" because most people don't have much "feel" in the torso as compared to the hands.This problem goes away,however,if the hands are fixed/connected to the torso as the swing starts if by this we mean when the torso strats forward.If the hands are then a proxy for the torso,they can let the brain feel how much to bend at the waist(make posture adjustment),and when the torso starts rotating forward.Jack considers separation as a "pre-swing" event with the swing or launch commencing only when the torso starts rotating forward,by which time,ideally the swing axis has been set.
> >
> > My interpretation may be a little different from both Jack and Mike.I think the body starts each swing for a given situation the same with rhythmic separation/closing or coiling/uncoiling.The body has a certain range of motion it can work within.While this generic coiling uncoiling motion is underway,the brain begins to narrow down the location of contact and starts making specific adjustments you have learned to automatically/subconsciously get the hands where they need to be to put the sweetspot on the contact spot.The "intent" of the brain/hands is implemented from the bottom up by accelerating hip turn,linking the hips up to drive the torso,then decelerating the hips which is what gets the energy of the lower body into the torso(transfer of momentum).This rapid acceleration of the hips could happen while the torso is still turning back or while the body is still stretching or coiling,or it may happen after uncoiling has already started.However,in any case,the hips still lead the hands.I think some diminishing axis/posture adjustment is possible but must be completed before the hips begin deceleration.
> >
> > As Jack points out,energy can not transfer well from the turning torso to the bat if the handpath straightens.To remain connected as uncoiling begins it is important for the hands to stay back and in the arc of the hand path.The bat can still swing out via tophand torque while the hands stay back,in and connected.The more it swings out prior to rapid hip acceleration,the higher load/resistance to rotation there will be.
> >
> > If this is the case then it is OK for the arms/hands to be "working" before the hips rapidly accelerate their turn IF by working we mean they stay connected and get no further from the body's center of rotation as they work.You can have preswing torque or top hand torque as the torso turn starts,but the hands should not start "working" by getting away from the body.Using the Epstein cues,you still have the "hips leading the hands" and "the hands stay in."(this would be followed by "weathervaning"which is the feel of some ongoing axis adjustment in Epstein's system as I understand it.)
> >
> > This very minor adjustment in the initiation of the swing(how far top hand torque has proceeded to swing the center of mass of the bat out before the torso is fully energized) creates a range of bat trajectories that can cover the strike zone.For the outside pitch,the energizing of the torso is slightly delayed and when the torso turns the load(mass of arms and bat further away from center of rotation)is higher.To use the torso energy efficiently in this situation,hand torque needs to fire the bathead toward extension rapidly folowed by some degree of the lead arm casting to get the right swing speed and radius for contact.If the hands extend away from the body before the bathead has been torqued out,energy transfer will be less efficient and more variable leading to excessive timing error.If the bathead isn't fired rapidly,the energy may not get sucked out of the torso during the more limited rotation of the torso as compared to the full torso rotation of the inside pitch.
>
> Tom, I gotta run & I'll respond in more detail later. However, my short response is that you are confusing the issues. The issue is not which method produces more energy. I agree that the more hip/shoulder rotation you have, the more power. The issue is the optimum contact point and you simply can't hit something when you are swinging AWAY from it. I don't mean to get smart but I suggest that you go back to the tee and try some of the things I suggested in my dialog with Ray Porco.

A few more related(?) points.Your model might be more accurately decribed as an anatomical one.The model I have in mind is much more based on energy production and transfer.The basic premise is that this skill is primarily dependent on timing.Timing error must be minimized or cosistent contact is impossible.Other aspects(including the anatomical)must participate in a way that minimizes timing error.How is timing error minimized for a human biomechanical skill? Evidence seems to indicate that you want to create a combination of the shortest path(path of sweetspot launch to contact in this case)and you want to traverse this path as quickly as possible(maximum batspeed in this case.)The latter of these seems counterintuitive,however,the hypothesis is that when the body is working to maximize batspeed,the duration of the swing from launch to contact becomes much more consitent which is most important in calculating how to get the sweetspot to the contact spot on time.If you learn to do this as much as possible so the contact target(point in space)is roughly perpendicular to the pitch direction,then being slightly early or late still gives good production.

Jack makes a compelling case for the necessity of the circular handpath with the hands controlling swing trajectory within this handpath by how/when torque is applied.Extension of the handpath prior to the torso receiving energy from the lower body or before beginning the transfer of this energy from torso to bat by torquing the bathead out toward extension will cutoff energy transfer and ruin timing.(Jack also highlights the important aspects of the axis of rotation.)

On video analysis the degree,sequence and timing of torso turn is a reliable analytic detail.The degree of hip turn is less so.What is most important with the hips is when they decelerate to transfer momentum and energize the torso.While they turn more early in the swing for the inside pitch,they also decelerate sooner,so it is possible for them to have turned as much for a more outside location since they can proceed for a bit before rapidly accelerating/decelerating.

Torso turn is less for the outside location because the simplest adjustment is to have hand torque create a higher load situation so the bathead has to fire followed by some casting of the lead arm before contact is made.Any lead arm limitation is from the load and not from the arm running out of room because the front shoulder wants to keep turning away from the contact spot.This gives a simple method of adjusting and creates the shortest path to the ball with the highest batspeed.