Friday, December 10, 2010

Pressure to floor at kime


Sensei Nishiyama always stressed that at impact one should apply maximum pressure to floor. Pressure to floor is actually one of the most important components of kime, and is a special point to karate technique. Another very important component is the sharp contraction of total body musculature to technique line, which I will explain at another time.

Sensei Nishiyama went so far and many times would say: “kime is pressure”.

Let me try to explain pressure, I will start by saying that mass by acceleration equal force, and pressure is acceleration and therefore most important for force production.

When one apply pressure to floor properly, the reaction from floor can equal 2 to 3 times body weight, that is huge acceleration, and especially important in short range when we cannot create big momentum.

Pressure to floor is also a mean of energy delivery, for example, we can compare it to a long jump, a person runs and creates momentum, but for this momentum to transfer into a jump, to become a jump, one has to hit the ground as sharp as possible.

Likewise, from start of technique till contact can be compared to the run up, and than to transfer the energy into the target fully, one has to apply pressure to the floor, the pressure is additional acceleration and at he same time allows for full transfer of the momentum.

Now, a jump is different than karate technique, since in a jump the purpose is to lift the body as high or far as possible using the momentum and ground reaction, in karate technique on the other hand the purpose is to transfer the energy to the opponent, the body is the vehicle for transferring the energy.

Therefore, unlike in a jump, in karate technique at pressure the body should not bounce up, since any bounce, any wobble, means escape or leak of energy.

In karate technique at pressure the whole body is still for a moment, yet the momentum continues through the target, we say “outside stops, inside don’t stop”.

This outside stop is only for a short instant, enough to transfer the full momentum and energy.

How to make pressure at impact?

We use the breath to apply maximum pressure to floor with the intention of reaction from floor being absorbed through the body and delivered to technique line.

One must avoid thinking of hitting with the fist, because that will nullify the effect of pressure and will cause undue tension in the top body, remember that power is indirect, a reaction.

Other important points to remember are that one should not slam the floor or “muscle” the pressure, but just use the breath.

If one “slams” the floor with the legs and feet, energy escapes, and there will be stress on the joints.

Also, the body should not rise and drop, does not change level, the pressure happens internally, without external change, it might be useful to have the feel of dropping internally.

For the pressure to be effective, posture has to be optimal, since if any joint is out of line, pressure will escape, and the reaction from the ground up will not be complete, we must have clear channels to transfer the reaction of the pressure from the ground up to technique line.

Breathing does not stop-

Breath make pressure to floor but does not stop, rather the breath passes through target, if one cuts the breath, pressure stops and the momentum stops.

Pressure to floor has other benefits besides acceleration and force delivery, when we make pressure, we create a spring internally, which is potential energy, which can be released into next technique with next exhalation. Pressure also help maintaining balance.

There are different methods to help the student understand how to make pressure, but those have to be demonstrated and hard to explain in writing.

5 comments:

  1. Very good article! A lot of people don't understand that principle. I do but it's very hard to do!!! Keep on practicing I say to myself! Thank you for putting it in words.

    Martin Bergeron, Sherbrooke, Québec, Canada

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  2. Thank You, Avi very much! Nice article! Pressure is very important for kime, like Sensei use to say:"No pressure, No points, No karate!!!" :)
    Thank you one more time!

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  3. Dear Avi sensei. Even if someone does not "slam" the floor, it can be dangerous for joints. The bigger preassure the bigger the force. Bigger force equals bigger acceleration. Bigger acceleration equals bigger shock. It is known that shock bigger than 3xg (3x9.81 m/s2) can cause death ;-)

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  4. Thank you for your all bloggs, I am back in dojo after 8 years.In the past when I was 26yers old and 2nd Dan, I thought that I know everything about karate. I was really stupid.
    Now 34 years old I am a student under your friend Sensei Jan Hrbacek.

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