Mar 25, 2008 10:35 pm US/Pacific
Good Question: Breaking Boards
SACRAMENTO (CBS13) ―
Breaking boards is in all the great martial arts movies, although it sometimes looks fake. But according to Michele Elefante, an instructor at the Okinawan Karate Club in San Francisco, the secret of a karate strike is simple physics.
In fact, one famous study found that a well-thrown karate strike moves at about 24 miles per hour, and will generate about 675 pounds of force when it lands. But the secret to breaking the board is also how it lands.
When you hit a golf ball, for instance, the follow-through helps propel the ball through the air, but it also disperses some of the shock waves, because you're trying to move the ball, not break it. Karate strikes do the opposite; snapping back, shortly after the point of maximum impact.
With no follow-through, the shock waves oscillate through the wood, tearing the fiber. Factor in the strength of human bones, and the board doesn't stand a chance.
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