Posted by: tom.guerry (tom.guerry@kp.org) on Mon Oct 29 13:16:19 2007

Jack -

Thanks for sticking with this.>>Comments between >< below<<

Hi Tom

Yes, the Findings from my study with a Motion Analysis Computer concur with Zig’s Findings. However, neither of these Findings in any way support your (and Teacherman’s) contention that shoulder rotation should be restricted or that energy for the swing is not transferred by shoulder rotation.

Zig states, “Good athlete = 550>750>1000=2000 degrees per second (rotational bat speed)." --- This means that during the swing, the angular displacement rate of the hips peak at 550 degrees per second while the shoulders peak at 750 degrees per second. Yet, Teacherman contends that the energy must come from the hips because shoulder rotation is to slow and would result in bat drag.

>> I think some of the disagreement we have is from confusion of fact with feel, and some is due to our differences on small factual details that may be nonetheless significant in how teaching/learning/analysis is approached<<

Tom, you and Teacheman seem to be reading from the same play-book in this discussion. To better clarify your position, would agree or disagree with the Teacherman quotes below?

(A) “You see....the hips rotate. The shoulders do not.”

>> I would say BOTh the hips and shoulders turn with hips leading. A shared definition of "rotation" is probably the most difficult thing here. That could take a while to sort out bu t may not be necessary<<


(B) “Shoulder rotation occuring at the same time as hip rotation simply can not and does not work.

>> agree, it is probably not even humanly possible to lock the two together during turning<<


(C) “The hips and shoulders moving together in no way proves the existance of shoulder
rotation.”

>> I think the question is how the hips and shoulders move relative to one another, most importantly the "universal" (attributes common to high performers/setting them apart) sequence of motions, which is most productively described in my opinion for purposes of factual discussion in terms of kinesiological joint motion sequence/proprotion<<

>> so in summary, there needs to be a good distinction between fact and feel and a shared definition of terms to develop a shared swing model that we can agree on.

I think your multiple arc/chp/torque model is by far the best descrption of the swing, but is not comprehensive enough to inform all teaching/analytical issues. No one is perfect, but your model is about as close as an excellent single author attempt would get.

No one person, however, has or even can have the total answer which requires a diversity of perspective that exists neither in a single person nor even in any group of people. However,more comprehensive info can be developed by reconciling the perspectives of a group of people than can be developed by a single individual as longs as the same reality is being described, in this case the reality we are aiming for being the mlb swing pattern.

In developing this additional necessary compelementary/"missing" information, the most helpful info is often found in other highly developed domains such as motor learning or computer modelling or descriptions of other skills, assuming that the human being will employ real life solutions that are diverse and studied by different sets of specialists. There is a big opportunity in figuring out how to fit these complementary pieces together.

In the case of how the hips and shoulders relate in the swing, there is highly developed and applicable/relavent info now available from experts in golf that sheds the most light on this question.

Jack, as you have admitted, you have found no obvious universal video supported landmarks for the lower body/weight shift aspects of the swing. I think this has not been too much of a limitation because you have the upepr body largely right and understand how this dominates the overall pattern.

On the other hand, it is well known that the swing works in golf and hitting by the kinetic link/summation of velocity/whipping type action that you and Zig among others have measured.

In golf this kinetic link has been studied much more and much longer and by many more people and there are key learnings here that I think directly apply from that domain to both the facts and feel of how the hips and shoulders relate in the swing, golf and hitting.

The best source of this golf info is in the explanation of Jim Hardy in his books/DVD's, THE PLANE TRUTH.

What Hardy has found is that there are 2 basic ways of sequencing the kinetic link in golf and that swing teaching/learning benefits from anlaysis based on knowledge of these 2 basic models in there "pure form" with the individual's swing being a hybrid between the 2 models.

The basic primary determinant of the overall pattern is how the arms are connected through the shoulders to the body.

There are 2 choices, either you swing the arms around the body in the shoulder plane which is called a 1 plane swing, OR you form the plane of the swing by BLENDING the turn of the body with the swing of the arms. Arms swing up and down as body turns back and forth rather than turning arms back into the shoulder plane then swinging them in the shoulder plane.

This 2 plane blend is the way mlb hitters have to do it to permit early batspeed, swing quickness and plane matching.

The way the shoulders work in these two patterns of kinetic link execution FEELS very different. The video appearance of the difference is more subtle AND the fact that individuals are all hybrids makes the videoanalysis very challenging in golf.

In mlb hitting, the pattern is MUCH more homogeneous as ONLY the 2 plane type action works adequately for successful mlb hitters.

YES, the shoulders and hips BOTH turn in both patterns, but the sequence and amount or proportion of joint motion and moreso the feel is VERY different.

2plane is hips and hands in mlb or in golf it is hips and arms.

1plane has not been used much in hitting until Nyman and Englishbey popularized their PCR or PCRW technique which turns the bat in the shoulder plane and adjusts up down by bend at waist and adjusts in/out by handpath hook. This pattern may be OK for hotbats with a long,wide sweetspot or against pitchers with lack of command, but this has not worked in mlb where pitching is the highest level and woodbat sweetspot and moment of inertia is required.

In hitting, relative to golf, the swing must be shortened and quickened which it is by using a shorter swing radius via a bent lead arm and using the shoulder tilt to help adjust timing and direction of load, both the arms and shoulders being controlled by hands that are used to deliver torque to the handle.

In golf, the limitation of the 2 Plane swing is that as the swing plane gets very vertical/upright/steep, the error from hitting shots fat or thin gets too great as does the timing error for closing the clubface.

In hitting, the challenge from good pitching and a small sweetspot and limited reaction time would seem to provide an impossible task, however, since you are not hitting the ball off the ground, the fat/thin penalty is not as severe and the sweetspot on even the wood bat is longer than the face of the golf club and there is not a clubface closure timing requirement that also must be controlled.

For this reason, the plane of the swing can be directly lined up with the plane of the pitch analagous to hittng all golf shots with an entirelt vertical plane that kept the golf club always swinging on a plane lined up with the target.

The body can not do this plane matching by swinging the club/bat consistently in the same plane around the shoulders. Instead, the hands control the swing of the arms and the tilt of the shoulders to match the plane of the pitch and to time and direct the swing based on how this action works with the turn of the hips and body to together blend and create loading and a swing plane that can start quick acceleration deep/eraly in the swing plane.

The feel of both 2plane golf and mlb hitting is hips and hands(mlb) or hips and arms(golf) or Swing down (both) or keeping the shoulders in there/not flying open (mlb) or not swinging over the top (golf) or not hitting around the ball (golf,mlb).

RElatively speaking, in BOTH 2P golf and mlb hitting, the shoulders are not actively turned because that would cause coming over the top and hitting around ball (golf) and loss of early batspeed (mlb).

In 1 plane golf or PCR hitting, shoulders are turned actively along with torso and even hips which gives a different sequence and relative timing of segments. Coming over the top is limited by keeping hands in tight (alligator arms) to body and bending way over. Then you can swing the arms and club/bat around the body without drag or coming over the top. This works fine in golf, BUT it can NOT work in hitting(mlb) becasue the only way to get adequate early batspeed is to create a HUGE amount of xfactor/separation between hips and shoulders like a 1Plane golfer does, turning the shoulders WAY back (in 2 plane, you tuen the hips AND shoulders back which limits separation/x-factor). In hitting, there is no time to do this.

The one plane golfer leaves the front foot flat on the ground and bends way over so that the shoulders and hips turn in very different planes. Then they limit the backswing of the arms so that the shoulders turn WAY back with huge xfactr, the club gets into the shoulder plane and does not get much past horizontal at the top.

Turning the shoulders back like this in hitting is "excessive counter-rotation" to use a PCR term, and either you get early batspeed by excessive counterrrotation or early batspeed is impossible because your swing has to be short enough to deal with reaction time. You can only function if you guess right, unless you have a hot bat. Having a predictable pitcher helps too.

In summary, even though the hips and shoulders both turn in hitting and golf, all swings, the way they participate is VERY different between the 1 and 2 plane methods of sequencing the kinetic link, and only the 2 plane variety can succeed in mlb.

relatively this means it's hips and hands and shoulders tilt/not turn and are bypassed in terms of feel. In terms of fact, the differences are less apparent. But to teach and learn, both the feel and the facts are important. And the DETAILS of the facts are different (subtle) for 1 vs 2 plane kinetic link sequencing.