The hand of a karate fighter can develop a maximum speed of ten to fourteen meters per second and exert a force greater than 3,000 newtons . This means that, in theory, it would be capable of generating energies between ten and one hundred times greater than that necessary to break wood or even concrete.
The question would then be, why don't martial arts experts who, as can be seen in some demonstrations, break bricks with it, even when they don't protect it, don't break their hand? It is clear that it could happen, but the truth is that the modulus of rupture of a bone, that is, its resistance to bending traction, is forty times greater than that of concrete . In essence, this means that a piece of bone two centimeters in diameter and six in length supports a force eight times greater than that exerted by concrete on the hand in a karate stroke, for example.
Now, a study published in 2012 in the journal Cerebral Cortex showed the obvious, that is, that skill is better than strength. After comparing the blows made by a group of twelve neophytes with those of twelve karate experts, a team of researchers from Imperial College, London, and University College, also in the British capital, discovered that the secret is not found so much in the muscle power, but in the ability to coordinate maximum shoulder and wrist speed . To determine the speed of the blow, the scientists attached infrared sensors to the limbs of a group of volunteers and recorded their movements.
Image: USAF / Dan Rohan
