December 7th, 2014

From Sensei Lyle Kleusch, San-dan, Shihan

Ueshiro Mesabi Karate Dojo

Rotational Acceleration

Onegaishimasu Hanshi, Kyoshi, Sensei, Senpai and Deshi,

This week’s technique of the week is about creating more force in your techniques through greater acceleration. According to Newton’s second law of motion, the fundamental formula for finding force is:

F = ma

Where F is the force, m is the mass of an object and a is the acceleration of the object.

The mass is our own body. The acceleration is how fast we move our body and its parts. Many of us understand the straight line movements of our blocks, kicks, punches, smashes and strikes. But there is more to generating maximum force than just moving our body, limbs, feet and hands from point A to point B as quickly as possible in a linear fashion. We can add significant acceleration (and therefore create greater force) through additional rotational movement in conjunction with our linear movement.

As a simple example, when you execute a chest block, you should cover the solar plexus with the blocking hand to the outside, palms facing outward towards the opponent. Then as you block, at the very last split second as you contact the object you are blocking, you should rotate the blocking forearm into the palm facing your position. This rotation, if well-executed, adds significant acceleration to outward linear movement of your forearm, greatly increasing your acceleration and therefore force.

Although this principle is not directly stated in Master Nagamine’s book. The Essence of Okinawan Karate-Do, it is implied and obliquely referred to several times. For example, on the bottom of page 83, Master Nagamine states: “This (middle inner block) is formed by a snapped motion of the forearm.” Here he uses ‘snapped motion’ to refer to the rotational acceleration that we instigate as we finish the block. Also, on the bottom of page 89, Master Nagamine states: “(Figs. 22a,b,c) The arm is bent at a 90-degree angle, with the wrist in line with the shoulder; the outer blocking edge of the knife-hand twists from the opposite shoulder to its contact position.” In this case Master Nagamine is referring to rotational movement as a ‘twist’ in order to add acceleration or snap.

Rotational acceleration is not just limited to blocking, either. In fact, the opportunity exists in nearly every move we make as we train. Our hips rotate into our techniques as we complete them, adding acceleration. Our opposite hands drive back into the pocket as we complete our techniques, again adding even more rotational acceleration. There are many more examples. In fact, nearly every muscle of our body, if relaxed and used correctly, will add to our rotational and linear movements for the completion of a devastating technique. Just remember to root into a balanced foundation and complete the technique with 100% dynamic tension at the instant of impact.

Study this concept well and apply it to your training. Ask your Sensei or Senpai if you need clarification.

Arigato Hanshi, Kyoshi, Sensei, Senpai and Deshi!

Sensei Lyle Kleusch,

San-dan, Shihan

Ueshiro Mesabi Karate Dojo