Yōso-fundamental elements

In his book “Don’t think, listen to the body”, Akira Hino discussed the skill of Hakkei (instant or explosive power). To perform such a skill, the sensation line of Rendo is needed. In fact to actualize a technique, a precise line of sensation is needed. To create such a line, a precise understanding of fundamentals is needed. This is not about techniques or so called basic principles as for example “kuzushi”.

Kuzushi is called balance breaking or balance disturbing and is the result of fundamental actions of moving the body. So, kuzushi is not a fundamental element but rather a basic manipulation action to create a successful technique (kihon waza).

Taijū no ido & Taijū no dendō

It is possible by using martial techniques to identify certain yōso (fundamental elements), such as the displacement of the body weight or transmission of the body weight. (体重 の 移動, taïjū no idō, body weight shift and 体重の伝導, taïjū no dendō, body weight transmission).

The displacement of the body weight (body weight shift) is when we move in such a way that we shift its center of gravity and the transmission of the body weight is an advanced use of the displacement of the body weight which allows to use the weight of the body to the other without giving access to the opponent. Strictly speaking, the displacement of the body weight consists of moving by making of its body a single block. For example, moving forwards, or backwards, by being a solid block. The use of gravity is a fundamental element for a succesful waza.

Using gravity

Gravity has a direct relationship with body weight. When we walk, basically we use gravity to move forward or another direction. The movement of the foot has an image of a rolling ball: 足 の 転 び, ashi no korobi, rolling or rocking the foot.
Be light like a rolling ball …and let gravity do the job.

The knee of ashi no korobi is used to create “kuzushi” or using gravity. The body will fall forward in this example. By using the skill of moving the foot forward, the balance of the body will be kept. Unsoku-ho of the exercise of foot movements is using in many cases the skill of ashi no korobi.

Waza, a personal skill

Waza or martial art technique is a personal skill and will be very difficult to teach another person without bodily understanding of fundamental elements. A technique has several fundamental actions and those movements are called gi-jutsu and should be acquired by training and not the waza itself. Waza belongs to the individual, and only yōso * can be taught by the sensei.

Yōso* : literally translated as “principle”, but in the context of our study we use “essential element” or “reality based upon laws and rules”.

Yōso (fundamental elements)

Another important yōso (fundamental elements) is the internal line of motion or undō-sen. Power is needed in order to move the body. Because power has to travel through the body to reach the target and we just have to become aware of the line of motion. Some lines of motion are very obvious. Other are hidden inside the body.

Take for example swinging the arms. The outward movement can be understood by everybody. But if your teacher tells you to swing your arm with the help of the hara, the center of your being. Can you feel the line of motion?

Feeling the line of motion is one of the core fundamentals in martial arts.

Internal line of motion (運動線, undō-sen).

Rendo is the skill of linking body movements with the result of a waza. This linking of body movements is only possible when we “feel” the body and in other words feeling the line of motion, especially the internal one.

Try to view the body in a 3D format. The internal line of motion is a diagonal line from corner to corner. See picture cube.

Linking the movements of the arm or leg to the internal line of motion is a big challenge for all serious martial art practitioner. Can you detect the line of motion? And can you feel the line of motion when you perform such a movement?


Tenshikei or using the internal spiral line for power is already a few times discussed in this blog. In the 3D picture above, there is the perception of a straight line. Of course, in reality the line of motion is following a spiral line. By feeling this line we can transfer power to the tarvet via the arm and hand.

The role of kyokotsu

Hino’s book, previously mentioned, has some explanatory “kyokotsu” pictures. Please visit Amazon to buy the book

Kyokotsu is the lower part of the breastbone. By moving kyokotsu forward or backward, a movement is created in the back muscles (open and close).

Kyokotsu has also a moving effect on the spine, especially the lower part (koshi region: psoas and iliac muscles).

By connecting kyokotsu to arms and legs, a full body movement can be performed. It takes at least a few years of practise to create such a skill. The associated waza becomes more efficient and with the correct strategy gives you a chance to control opponent.

Using fingers and elbows

Connecting elbows to the kyokotsu can be very helpfull when you are grasped by opponent on the wrist of forarm. As explained previously, there is a connection between a moving kyokotsu and the back muscles. When kyokotsu is moving inward, the back muscles will push the elbows forward. When the elbows are pulling in, kyokotsu will move forward.

Do we have to focus on kyokotsu when moving the elbows? No, if we can observe the line of motion, the body will do the job. The difficulty is in the conscious mind which likes to take over the process of moving the body. Just become an observer, don’t interfere in the movements.

When pushing with the elbows, there is of course a limit in the distance. Here start the movement of the hand with the fingers. By stretching the finger into the direction of the target, a pulling action is activated in the forearm. This is already discussed in an earlier post about push/pull action. The mind has an important function. When we can feel the line of motion in the arm (the example of elbow and finger), we can use an image of reaching a far mountain at the horizon: anzen no metsuke.

The relationship with opponent

During our training of martial art, especially aikido, the word harmony is often used to express the relationship with the opponent. Of course harmony has many definitions and harmony in aikido is not an exception.


Generally, awaséru is translated to harmonize with, to match … Harmony is primarly a mental state and the body will follow accordingly.
Therefore you should not go together with the gestures of the partner but with the conscience of the partner.


Listen to the opponent. The extreme development of bodily sensibility, does not only concern the capacity to feel the force and the direction of a physical attack, it is also a question of feeling the intention of the other and changing the intention via a point of contact, physically or mentally.
If one is not capable of chōkei, one can consider that all that one does is only gymnastics. ” Chōkei has a direct relationship with harmony, because if there is no chōkei we cannot create harmony.


Wagō, means harmony, concordance, agreement, union, unity …
We often talk about “harmony” in Aikido. The Japanese word for harmony used in aikido is wagō. This word is made up of the kanji 和, which can be read wa and which notably means harmony, peace; and kanji 合, which can be read aï or gō and which could be translated by matching, agreeing, going together …


Aikido can be explained from different point of views. By using the conscious mind we can find a rational definition for this martial art. By using the unconscious mind, the concept of feeling is more important and the conscious mind act as an observer. Trying to express in a rational way, maybe we will miss the real purpose of aikido. Therefore describing aikido via a poem can express the feeling of the movement……maybe……