Strength of mind allows the person to carry out the full control over itself. «Behind a side permitted» to operate the body, and even the opponent. A single combat vivid example which wins the strongest and the cleverest is sumo. It is very ancient version of traditional Japanese struggle. Historians cannot answer a question with reliability: whether there was a struggle sumo in Japan or this ancient single combat was is brought from other continent.
The Japanese struggle sumo has no analogues in the world.
Japan — the recognised centre sumo and one in own way the country in which there are competitions on professional sumo. In other world compete only in amateur sumo.The ritual component of the Japanese struggle sumo has long since remained. The scenario of preparation for a duel does not change centuries, and it helps to keep atmosphere of ancient Japanese struggle.