Sun Shi Xing Yi was created by Master Sun Lu Tang, on the basis of what he learned directly, since the age of 15, from Grand Master of Xing Yi, Guo Yun Shen. Compared to the other schools of Xing Yi, Sun Shi Xing Yi has a style that is simple, solid, discrete, reserved, flexible and light. This specific style is the result of the following characteristics:
1. Centre of gravity on one leg.
In the basic position as well as in movements, the principle of Sun Shi Xing Yi is that the weight always falls on a leg. One does not find the horse riding stance or bow and arrow stance. This principle makes possible an apparently contradictory requirement – the body is at the same time stable, heavy like a mountain, and flexible and light like a bird. Indeed, the axis which supports the weight must be stable and heavy, it is Shi (full), the remainder of the body must be flexible and light, it is Xu (empty). Shi is the base, Xu is the tool, and both are made possible mutually.
2. The position is relatively high.
The angle with the knee should not be lower than 135 degree. The steps are relatively small, the principle being that the movements should not be difficult. Thus, contrary to much of other schools of Xing Yi, Sun Shi Xing Yi does not seek the large steps and the low position. Two advantages rise from this characteristic: on one side, the natural position of the human body is respected, the wear of the knees is avoided; on the other side, the balance between flexibility and stability is balanced.
3. The striking force is a turning force, on three dimensions.
In Sun Shi Xing Yi, the striking force is based on the axis of gravity (head – back – supporting foot which supports the weight). All force is accumulated in the middle of the axis, i.e. with the bottom of the back and the hip. When one strikes, there is at the same time a force generated by advancing the axis, and a force generated by the rotation of the body around this axis. The two forces form a force of three dimensions. For example, contrary to much of other Xing Yi, in Pi Quan within Sun Shi Xing Yi, in the movement of Pi, the rear leg does not follow step, with a result that the force directed forward has decreased; but the rotation of the body gives the striking an additional dimension , the result is in fact reinforced.
4. The position of the hands is vertical.
Hand and arm form an angle of 90°. It is a major modification which Sun Lu Tang introduced during his last years. Front, the hands are positioned horizontally. When the hands become vertical, the muscles/tendons lengthen themselves, the force of the arms and the feeling of Qi on the hands increases considerably. This position of hands is adapted also to the need of true combat.
5. Two different kinds of exercises: exercises on thickness and solidness; and exercises on lightness and flexibility.
In Sun Shi Xing Yi, Wu Xing Quan (five xing) are the basic exercises, they require the thickness and heaviness, the five Quan correspond to the exercises of five different forces; while Shi er Xing (Twelve Xing) are the exercises of application, they require lightness and flexibility. In true combat, it is firstly necessary to seek not to lose, by flexibility; and then to seek to gain, by using force. Thus, the way of exerting Wu Xing and Shi er Xing are different, it should not be mixed.
6. The use of the force must be reserved and discrete, flexible outside and hard inside.
Sun Shi Xing Yi requires that the muscles and the articulations must be relaxed, while the axis head – back – supporting foot must be solid and stable. The force must be preserved inside the bones; the Qi descends to the Dan Tian. The power is felt inside, but does not show itself outside.
7. The gestures are simple and practical.
In Sun Shi Xing Yi, there are no movements of decorations, nor movement of transition or preparation. This comes from the principle that the simplest gestures are the most effective.