Posted by: tom.guerry (tom.guerry@kp.org) on Fri Nov 4 16:52:03 2005

Jack,Jim,et al-

Jim brings up an extremely important point about the hips leading,but not sliding. Again,I find the information from golf concerning weight shift AND "spine tilt" the only place this is adequately noted and explained.

To understand this,it is necessary to understand that there are different overall patterns that the swing organizes around,the two most effective being "spinning" and the highest level "whipping" (whipping includes efficient transfer mechanics via double pendulum/2 segment whipping of the arms/bat).

In golf,this is explained as one plane (spin) vs 2 plane (whip). The important point is that attributes of the 2 patterns can not be mixed without degrading performance.The spin/rotate/stay connected swing works by having less bat quickness,but using a trajectory that keeps the bathead in the desired (hit decent fair ball) contact zone longer.

This swing is optimized more for placement and less for timing precision-the old fashioned short to/long through type swing.

This is different (and suboptimal for a good power swing) from the whip pattern which is optimized to minimize timing precision and maximize swing quickness with less emphasis on reducing spatial/trajectory error.

Breaking down the 2 patterns is done best in golf,see previous link to golf digest article which is extracted from THE PLANE TRUTH by Jim Hardy.

In hitting,the patterns have ben best described by Jim Dixon in his EXCEPTIONAL PLAYER book,but his focus is too much on body as opposed to arm action.If you put together Dixon and learnings from golf with Jack's arm action emphasis,then you can really optimize the swing.The Epstein material is further necessary for the late axis tilt/adjustment description.

As "evidence" of these golf propositions in addition to Hardy's book/article (as opposed to how exactly they might apply to hitting),see also today's NY Times,first page of sports section where Tiger Woods recent 2 plane to 1 plane transition is ilustrated/analyzed.

The one plane golf swing was made possible by the "modern" equipment,primarily the move from wood to metal shafts.Hogan was the first one to make the most of the move to the one plane swing.Jones was the master of the 2 plane swing and has described it best.As Jones points out,the "load" consists of a turning back and an arm lift component.The arm lift is minimized in the one plane and maximized in the two plane (John Daly and MIchelson are 2 planers).

Woods problem was that the timing of the arms and body turn could get slightly out of whack which then resulted in either a "slice to the right or a pull to the left" (see NY Times article). By moving to the one plane swing,the potential is for better "repeatability" by virtue of the fact that the clubface squaring is more predictable,usually eliminating the pull/hook type errors without sacrificing any length or even by increasing length by accentuating the body turn loading/separation from hip to shoulders.

Woods says (of the one plane swing):

"........what I try to do is swing on the angle of the clubshaft at address. For me, that's a consistent swing plane that matches my arms and body. It takes timing out of the equation."

The article goes more into depth on the exact flaw analysis/pros and cons of one vs 2 plane swings, but the point is that the 2 plane swing permits more precise timing/lower timing error,but at the price of having to worry that a mistake could go either right or left which translates to too much uncertainty.The one plane swing increases spatial accuracy so clubface angle errors are more predictable while timing of contact is less precise (higher timing error lower spatial trajectory error for one plane swing).

Now,to talk briefly about how this applies to hitting,the ideal swing in hitting is similar to the 2 plane swing becasue job #1 is to reduce timing error with spatial erro remaining acceptable. There is no clubface angle to worry about,so spatial error can be focussed on less.So if you are trying to apply findings from golf to hitting,you should look at the details of the 2 plane swing pattern (optimized to minimize timing error) and avoid the (incompatible) details of the one plane pattern.Jones describes 2 plane well. Hardy describes both and points out the incompatibilities of one and 2 plane details.

Now,finally,this gets to Jims's point about hips leading head.This is a very important detail of the 2 plane and hitting swings as is the fact that in the 2 plane and hitting swings you need to shift the weight forward BEFORE the hips begin to unwind/turn forward (see detailed sequence of this "magic move" as described by Jones). This means that the spine will be slanted back from hips to head as the body "shifts forward" in the hitting and 2 plane swing.This in turn permits good coiling dynamics and good timing of the arm and body load/unload as well as setting up the late axis tilt adjustment potential as described by Epstein in hitting.
In the one plane swing on the other hand,there is no significant weight shift before hips unwind.You turn more "in a barrell" and you have the spine more erect,not tilted back so much.

Look at this detail comparing one plane/spin to 2 plane/whip:

http://www.golfdigest.com/search/index.ssf?/instruction/gd200505swingplane4.html

Notice the open side view of the player and read the description under "POSTURE".Note:

For one planers it says:WARNING: Do not tilt your spine to the right at address

For 2 planers it says:When viewed from the front, the shoulders are positioned slightly to the right of center of the hips, the spine tilted slightly to the player’s right.

So something is good about having the hips lead so the spine tilts back in the 2planer/whip type swing optimized for precision of timing.

Now to get back to weight shift, motionanalysis of hitters (see illustrations at peavynet.com for example) show that typically the belly button/belt buckle/center of gravity traces a line forward and down,then stops forward progress and goes up.

For 2 plane golfers whose swing essentials are most similar to hitting,the weight needs to shift forward before the hips turn open/"unwind".

In both,the hips need to lead the head so the spine is tilted back as described above and by Jim in his post.

I think reasons you need this configuration- which are related to weight shift and not just hip slide- include this positions the spine to come forward which assists in creating coil in the body and sending the center of gravity UP optimizing coil dynamics for a quick swing and permitting late axis tilt adjustment as needed to increase length of contact zone relative to ball trajectory (level out swing/flatten swing plane/lean axis more forward for high hard one,tilt plane swing more up/lean axis back for offspeed/low ball).

http://www.youthbaseballcoaching.com/mpg/sosa_sammy3.mpeg

In this Sosa clip,for example,after the front foot is down,there is no hip slide, BUT the head can still come forward before axis is set and bathead fires out of arc of handpath.