This writing by Shizuto Masunaga illustrates the three basic rules of pressure at the Iokai Center in Tokyo. Enjoy the reading!

We instinctively lay our hand over the area where there is pain. This is called teate (手当て) in Japanese. Shiatsu is to give instinctive teate on behalf of the person who feels pain. Therefore, it is fundamental that one gives a pleasant pressure which is natural.
Rikyu taught something very obvious. “The innermost secret of tea ceremony is to suggest coolness in the summer and warmth in the winter.”
However, it is very difficult to grasp this naturality. As he even said “whoever is able to do this, I will become his disciple”. Therefore, it is necessary to first learn the etiquette. So what is shiatsu conforming to this naturality? I will explain it as three fundamental principles governing shiatsu.

1) Vertical pressure
A stable vertical pressure applied on the surface of the body is what we receive from our natural environment. And a living organism conducts its life reacting to this pressure. Abrupt, local and non-vertical pressure stimulates and tenses up the sympathetic nerves which could easily damage the living organism. This will excite the motor function and stimulate the blood circulation. However, this is inappropriate in the case of illness.

2) Stable sustained pressure
The vertical pressure is also used in anma and massage. Nonetheless, their pressure changes rhythmically. On the other hand, the pressure applied in shiatsu is stable and sustained.
The sustained pressure is usually applied for 2 to 7 seconds but it could be shorter as it could be held for 8 to 30 seconds or more. The key point in this sustained pressure is its stability. This allows the pressure to penetrate into the inner parts of the body activating the parasympathetic functions of the internal organs which in turn has a relaxing effect.

3) Sasae-atsu (supporting pressure)
It is difficult to give a vertical stable sustained pressure with the force of the fingers and arms. We can only achieve it by using the unconscious tonus of the muscle.
When we maintain a certain posture we do not consciously make a physical effort to do so, but we still are able to keep it for a long time. This is the work of the muscles supporting the weight. This is also true when we hold an object. This method is called sasae-atsu and it is also the pressure which is applied when we support ourselves while supporting the other person.
When we try to lean on the patient instead of pushing him, the person will entrust himself to us. This is what we call “interdependence”, which is expressed by the Japanese character for human being which is written 人 (the two lines represent two human beings supported by each other).
We can also say that the “two-hand technique” in which the hand giving a sedating pressure is continually supported by the tonifying hand pressure. This is what we call sasae-atsu.
When we agitate the body with a pressure given to a patient in an unstable posture, the body cannot relax and it will try to respond by tensing up the muscles and hardening the whole body. If the patient’s muscles are tense and not relaxed, no matter how much shiatsu we give, the pressure will not penetrate his body. When the pressure is given in one direction, unless the floor acts as the supporting force, the patient must be supported by a pressure from the opposite direction. The two-hand technique is also important for this sasae-atsu (supporting pressure).

In short, the patient must be relaxed when we give shiatsu. Therefore, the practitioner must be at ease, relaxed and gentle, and must have a supportive attitude towards the patient.

Shizuto Masunaga