The principal physical techniques of aikido are bending and twisting actions applied mainly to the wrist, elbow, and shoulder joints of the adversary. Although these twists and holds would not necessarily throw an opponent, the partners practice safety falls resembling judo and wrestling falls, and they respond to the aikido techniques by taking rolling and leaping falls. This aspect of aikido makes it a beautiful and graceful exercise. Aikido is practiced primarily in kata, or "forms," which are prearranged and rehearsed series of attack and defense actions in which the students alternate the roles of uke, the assailant, and nage, the person who is assaulted. The latter applies the holds and then throws the assailant. In addition to the principal weaponless techniques, there are also stick-fighting variations.
The practice hall or arena is called a dōjō, as it is in judo. The uniform worn for aikido practice consists of a cotton kimono-style jacket and the hakama, a pleated, ankle-length garment that is either like a skirt or split like trousers.
Colored belts indicate proficiency in kata. There are no universal standards of grading or requirements for promotion from one proficiency level to the next. Typically, however, the novice wears a white belt. Intermediate levels are indicated by a variety of color schemes, including a progression from orange through green and blue to brown. Expert level is indicated by a black belt. Aikido instructors may promote a student at their discretion. The student is expected to spend many years in training and practice in order to become proficient in aikido techniques.
Aikido was developed in Japan by Ueshiba Morihei as a result of a moment of enlightenment that he reportedly experienced in 1925; previously Ueshiba had studied jujitsu systems with the aim of becoming a superior fighter. After 1925 he worked out his system of aikido based on a quasireligious, mystical concept of a universal cosmic power called ki (Chinese, ch'i), which could be tapped for mental and physical control of an adversary as well as for spiritual uplift and purification and for bodily health. Aikido is translated as "the way (dō) of union with (ai) the life force of the universe (ki)."
Practice of aikido is linked to concentration on the "single spot" and the resulting pouring forth of ki. Students are instructed to concentrate on a spot just below the navel and to think of it as the center of the mind. Successful concentration is said to produce pouring out of ki, while imperfect concentration results in a temporary loss of ki. Prolonged loss of ki is thought to be the cause of illness, and permanent loss of ki is thought to result in death. Training for the control of the flow of ki through one's body is described as acquiring a sincere belief in its existence and in its power. Diligent practice is said to give the individual an understanding of the true laws of nature, make him or her impervious to assault and indifferent to fatigue, endow the person with a sixth sense of events about to occur, and make daily life free of anxiety.
