Last night I was channel surfing and caught the tail-end of Fight Science which airs on the National Geographic Channel. The part I saw was about 8:00 into this this video. The part that I cannot find in this video is when they scientifically compared yelling and breaking versus not yelling and breaking. (this came after the point where this clip ends) In a double arm break this guy yells and they measure 2,000 pounds of force on the stack of bricks. In the non-yell attempt he generates 25% less force, or 1,500 lbs.
The “classical” martial arts explanation is that you are learning how to channel your ki or chi into the strike.
The modern scientific explanation which Fight Science illustrated is quite different: The yell triggers the brain to synchronize the muscles into a unified strike. In effect the yell makes your core contract which simultaneously sends electric signals through the muscles of the arms and forces the muscles to work together. This is why the “push-pull” of a karate or taekwondo strike can be so powerful if done correctly. The other thing the yell does is to trick the brain into releasing performance enhancing chemicals including adrenaline.
The result? 500 more pounds of force when the world champion breaker yells!
All those ancient masters where on to something hundreds of years ago. However, they did not have a scientific understanding of how the body works. So for them “ki” became an explanation for something that still seems amazing even today.
~BCP
4 responses so far ↓
Matt (Ikigai) // June 2, 2008 at 12:43 PM
Ahh yes, fight science! I remember seeing this show a little while ago. Very interesting stuff how they break it down into physics.
Sometimes they seem a little fixated on finding the “ultimate” technique or weapon, but I suppose we have to give them a little latitude for television drama.
It’s cool to hear about kiai and the physiological effects it has on the body – so it’s not just for getting noticed at tournaments! haha.
Best,
Matt (Ikigai)
Bob Patterson // June 2, 2008 at 4:50 PM
Hi Matt -
No it’s not just for tournaments!
Think about it: That 25% difference was probably enough to make it so a warrior could punch through lacquered samurai armor.
~BCP
Chris | Martial Development // June 3, 2008 at 1:26 AM
Fight Science was intended as entertainment, and it is entertaining.
I trust their competence to measure well-understood physical properties. But drawing such conclusions from their limited data set, is like researching space travel by watching episodes of The Jetsons!
Bob Patterson // June 3, 2008 at 5:24 AM
Hi Chris -
By now you know I’m a seeing is believing kinda guy!
What I’ve seen and done points to physics and physiology, not ki. I think one man’s science is another man’s ki. I suppose if there’s one thing we can both agree on it’s that the ki-yap! actually does work. So whether it’s ki or science, there’s no denying this much.
For those of you who like physics and science see also:
http://people.howstuffworks.com/karate2.htm
http://72.14.205.104/search?q=cache:-nqvFDXOQiYJ:www.phys.ttu.edu/~cmyles/Phys5306/Papers/2004/Physics%2520of%2520Martial%2520Arts.doc+breaking+karate+physics&hl=en&ct=clnk&cd=6&gl=us&client=firefox-a
http://www.fas.harvard.edu/~scdiroff/lds/NewtonianMechanics/KarateBlow/KarateBlow.html
Or if you can find a library…
M.S. Feld, R.E. McNair and S.R. Wilk, Scientific American 240, 150 (April 1979): “The Physics of Karate.” For an analysis of the energy lost to deformation of an opponent, see J.D. Walker, Am J Phys 43, 845 (1975): “Karate strikes”