From: jon@zeus.med.utah.edu (Jonathan Byrd)
Subject: Re: poor technique
Date: Thu, 31 Dec 1992 17:13:19 GMT
	<1992Dec31.141900.12287@aber.ac.uk>
Organization: University of Utah

In article <1992Dec31.141900.12287@aber.ac.uk> azw@aber.ac.uk (Andrew Michael Woodward) writes:
   In article <1992Dec30.153837.25923@cs.brown.edu> tac@cs.brown.edu (Ted A. Camus) writes:
   >>(1) All attacks are focused short of where they would be focused in an
   >>actual fight.  That is, the attack goes to full extension, but that
   >>point at which the attack finishes is within an inch OUTSIDE the
   >>opponent's body, rather than an inch or more INSIDE, as they would be
   >>in an actual fight.  
   >
   >    This is perhaps the worst way to do this!  

   If you end a tightly focussed blow in mid air, the impedance mismatch means 
   that the force of the blow is reflected back up your arm and can do major
   damage to your tendons/joints/muscles. Very tightly focussed blows cannot
   be practiced in play, since you have a choice of either harming yourself 
   or your partner.

   What is the solution to this problem?

First of all, I was taught that one should keep body distance (ma-ai)
realistic at all times, and prevent excessive contact by retracting
the strikes before they fully extend.  As someone else mentioned, it
is much easier to control the extension of your elbow or knee than it
is to change your whole feel for proper distance.  You learn to
control the amount of damage you inflict by letting your elbows and
knees be a little more bent, or a little straighter.

With this in mind, the "impedance mismatch" problem is solved by the
forceful retraction of the blow.  One set of muscles contracts to
extend the limb, and the other set (the opposing muscles) contracts to
withdraw it, canceling the energy.  This method requires the input of
two separate energy pulses for each blow.  It is crucial to time the
withdrawing action to occur just a fraction of a second before the
desired penetration point.

It is important to note that even when you use full extension, you
must still have the withdrawing action.  You *never* let your arm or
leg go to full extension without contracting the withdrawing muscles,
or you may suffer hyperextended knees and elbows, and perhaps even a
separated shoulder.  So the real question is not whether we use the
withdrawing action, but when we use it.

Another advantage of this quick withdrawing method is that your arm
(or leg) is quickly in position to strike a second blow.  Some people
don't like the way it makes your strikes look like a "tag, you're it."
Being "tagged" many times has convinced me of its effectiveness.  As
long as your body distance is correct, you can be as nice or as mean
as you need to be by just starting the withdrawing motion a little
earlier, or later.

Of course there must also be disadvantages to this method, too.  One
problem is that it is very hard to time the withdrawing action
precisely.  You must also practice often with a heavy bag or hand pads
to maintain the feel of full penetration.

Are there other disadvantages to this method of controlling
penetration by limb extension?

--
jonathan byrd
jon@apollo.med.utah.edu