Posted by: BHL (Knight1285@aol.com) on Fri Nov 5 21:42:43 2004

Hi All
> >
> > This is a continuation of a discussion JJA and I are having below on the CHP and torque.
> >
> > (JJA)
> > >>> Agreed. This is not the issue. Jack claims that this circular hand path can only be created by torquing the bat handle, and I disagree wholeheartedly. -JJA <<<
> >
> > (Jack Mankin)
> > Hi JJA
> >
> > I have NEVER claimed, nor do I believe, that a "circular hand path can only be created by torquing the bat handle." -- That is a complete misrepresentation of my views. I have always maintained that there are two SEPARATE forces that induce angular displacement of the bat. (1) The CHP - generated from body rotation. (2) Torque - generated from the push/pull actions of the hands and forearms.
> >
> > I have often referred to (and is shown in our video) how the CHP generates bat speed independently of torque. If I believed a "circular hand path can only be created by torquing the bat handle", why do you think I would add the steering wheel knob to the bat (which eliminates torque at the handle) when demonstrating a productive CHP.
> >
> > Jack Mankin
> >
> > (JJA)
> > >>> Now you've really lost me. Are you saying that the circular hand path is created by applying forces to the bat handle?
> >
> > If so, please try to explain what's happening at the handle. I'm not trying to misquote you, but my impression was that you believed that bottom hand torque was the primary contributor to bat speed after top hand torque had ended. This meant to me, perhaps in error, that you believed that linear forces at the hands were small. Are you instead saying that linear forces are large, and that both torque and linear forces are important? <<<
> >
> > (Jack Mankin)
> > Hi JJA
> >
> > I am really amazed you are asking me these questions. Throughout my writings and in the video, I stress that a CHP is developed from keeping the hands back at initiation and allowing body rotation to fling them onto a circular path. Torque applied at the handle is not a factor in developing a CHP. However, it is a major factor (along with that from the CHP) in generating bat speed. If you don't have the video, I would strongly recommend that you go back to square one and study the swing mechanics and bat speed research page.
> >
> > In the video I demonstrate that a CHP accelerates the bat-head in the same way that swinging a ball on the end of a string accelerates the ball in a circle. As long as we keep our hand in a circular path, the ball will continue to accelerate in a circle. But once the hand-path straightens (more linear) the angular displacement rate slows.
> >
> > I have always defined linear mechanics as producing a more linear hand-path that results from extending the hands toward the ball instead keeping them back at initiation. I have also stated many times that the force acting on the bat from a circular hand-path is directed lengthwise (linearly) down the bat ("like swinging a ball on a string"). From some of your statements, it appears to me that you (and possibly Paul) are suggesting that linear mechanics are involved in generating that force. Do you consider the mechanics that produce a CHP or "flailing action" as linear swing mechanics?
> >
> > Note: We are running out of space. I will start our conversation as a new thread.
> >
> Jack,
>
> At least we're getting somewhere here. It appears that you agree that circular hand path and bottom hand/top hand torque are separate issues. In other words - and please correct me if I misinterpet - that swings works as follows: one takes a circular hand path and supplements it so to speak with top hand and bottom hand torque. Is this a fair interpretation?
>
> If so, let us consider the circular hand path. It appears from your last response that you concur that for CHP only, the forces are directed lengthwise down the bat.
>
> If so, then we're disagreeing about very little. The forces directed lengthwise down the bat, due to rotation from the lower body and torso, IS THE WHIP EFFECT. This is precisely what Adair is saying in his book. Note Adair does not advocate any hitting style in his book, rotational or linear or otherwise. He is a physicist, not a batting instructor. He is simply saying that forces are directed down the length of the bat due to rotation of the torso, lower body and near circular hand path.
>
> In other words, your circular hand path and his description of the whip effect are nearly identical, just described in different terminology!
>
> If this is true, our last disagreement is whether bottom hand torque and top hand torque supplements this whip action in a meaningful way.
> I'll take that up as this discussion proceeds. I'm just amazed, too, that you basically agree with Adair!
>
> -JJA
>
> > Jack Mankin
> >
Hi Jack and JJA,

I am oblivious to Jack's sentiments about the idea that I am about to submit to him, but let's hope he is in the best of humors. What I propose is a candid discussion between Dr. Adair and Jack, calling into question both explanations of developing bat speed that has stirred up quite a bit of turbulence recently. I implore both to examine the validity of each other's points, scrutinize the ramifications carefully, and then present agreements or objections based on empirical evidence, how well physical laws supports each model, and how much material supports each theory (I am speaking of dissentions over how angular displacement is induced, rather than whether a model is linear or rotational. Jack, I am sure that Adair has access to the internet, so I am looking forward to an open debate between dissenters. This gives everyone a chance to offer their opinion as to whether they agree with Jack or not, and why. Jack, will you embrace the opportunity to contact Dr. Adair, and partake in suck a debate?

BHL