View Full Version : The Tao of Jim Sullivan

Brad Waugh
10-15-1997, 11:57 PM
The search for Jim Sullivan has been unsuccessful.

It seems possible though that the true goal of our search may not have
been Jim but rather a a deeper biomechanical understanding of the
martial arts. In the interest of sparking a discussion on this theme I
will contribute my initial findings of the literature out there on this
topic. (Be advised that my literature search tended toward physics and
karate as my background is in these disciplines.)

There is a web page listing of references maintained by Kim Taylor at
This contains nineteen journal articles under the heading "The
Physiology of Martial Arts".

Lester Ingber maintains a page containing links to all his work in the
area of martial arts physics at
http://www.ingber.com/karate.html (thanks to Todd for this
This contains links to his textbooks on the topic and his E-list
contributions. (Dr. Ingber's work is aimed at the martial artist and
does not constitute research per se as much as a physics based analysis
of the art of karate.)

Wilk, McNair and Feld, "The physics of karate", American Journal of
Physics, 51(9), 783 (1983). (And refs therein). This is the most up to
date journal article I have read that describes physics research. It is
a more mathematically in depth approach to their article of the same
name in Scientific American, 240(3?), 150 (1979).

Blum, "Physics and the art of kicking and punching", Am. J. of Phys.
45(1), 61 (1977).

Walker, "Karate strikes", Am. J. Phys. 43(10), 845 (1975).

One area that I would like to address through research is the modelling
of striking techniques. When modelling the strike during a board break,
for instance, the above refs use the simplification of considering the
hand to be "disembodied" and flying through the air at, say, 10m/s.
When striking, however, the martial artist trains to "tense" the
relevant muscles at the last instant to involve the entire body mass and
even the flooring in the technique.

The simplification used by the physicists above is justified by photos
which show that the supporting joints in a strike flex in a way that
implies that the force is not transmitted from the body beyond the
forearm. However, individual experience tells us that a loose jointed
strike does not carry as much power. Further, I don't believe that
speed can be the only factor in a "good" strike with regards to power
transmission. A novice martial artist can throw a punch out at 6m/s
while an expert can get up into the 10 to 12m/s range or a bit higher.
Yet, the damage inflicted by the expert technique can far outweigh the
4X factor implied by the squaring of velocities (hence, kinetic energy).

No doubt a realistic model lies somewhere in between "free-flying fist"
and "body like a rooted tree", but where exactly? A more accurate
model of a strike will lack the mathematical simplicity of a two body
inelastic collison but it should be feasible given the numerical methods
available for similar "collisions".