Two Japanese characters make up the word: Ki means “energy,” and ai means “to unify.” The concept appears often in the traditional martial arts of Japan and in different ways. In the broadest context, it refers to ways in which an opponent is manipulated through means other than physical contact. That can include the use of vocalisations.

There are very sophisticated psychological ramifications of kiai, however, and they extend far beyond just shouting. A stare. A way of posturing. The “attitude” one exhibits in the face of conflict. All these can be expressions of kiais.

Shimada Toranosuke (1810-1864) was still in his teens when his swordsmanship made him famous on the southern Japanese island of Kyushu. Using a bamboo shinai, he won several contests. He eventually traveled to Edo (now Tokyo) and launched another series of challenges. Although he lost some, he began winning. A lot. His fame grew, as did his self-confidence, which, given his youth, probably fermented into arrogance.

Shimada challenged Odani Seiichiro, a small, nebbish-looking fellow who happened to be the 13th headmaster of the jikishinkage ryu. Shimada and Odani faced off; the former was convinced it would be a short match. To his surprise, he found himself slowly moving backward. Shimada did not will it; it just happened. Odani was stepping forward, his sword out but not looking particularly threatening. Shimada, however, said the experience was like facing a moving wall of kiai. Before he realized it, he’d backed up the length of the hall.

Odani relaxed, retreated to the center of the room and once again assumed the look of a chubby panda. Shimada followed, and they resumed their match. And once again, even as he struggled mentally, Shimada later recalled, it was as if a solid cloud was advancing on him. He was powerless. He found, in desperation and confusion, that his arms and legs wouldn’t work. He actually lost consciousness.

Afterward, Shimada begged to be accepted as a student of Odani’s ryu. He excelled and later founded his own branch. (Those who are interested in learning more about Shimada should watch the drama The Sword of Doom. Toshiro Mifune’s character is based on him.)

Accounts of this sort make kiai sound like magic — or perhaps a kind of hypnosis or method of mind control. Lest you dismiss it as so much nonsense, take a look at, for example, videos of systema experts. Don’t concentrate on their techniques. Instead, look for the way they move and stand as they speak. They exploit posture, facial expressions and physical size. All work not as a substitute for talent but as a way of establishing control.

We like to think of magic as something embraced by primitive, unsophisticated people who are intimidated by any threat of a power that’s not seen but is somehow communicated. All humans, though, are susceptible to suggestion, to almost-unconscious clues we pick up from the behaviors, expressions and movements of others. This is where the realm of kiai exists in serious martial arts.

Just in terms of the vocalization of kiai, the subject is still far more involved than many know — especially those who shriek like a banshee who’s just stepped on a Lego as they do their kata “performances.” In classical ryu, specific vocalizations are taught. Some sounds tighten the muscles in the back that are used for thrusting; others engage the abdominals that enhance striking. The sounds aren’t spontaneous squawks or roars. They have a deliberate meaning.

A vocalized kiai might be used to confuse or distract an opponent, just as loud noises of all sorts will do. But it also can disrupt concentration and impose one’s will to exploit weakness in an opponent. The key here is to remember the actual meaning of the word: to unify or harmonize one’s energy with that of another person. In this sense, kiai is about infiltrating the mind of an opponent, then controlling it.

Again, this might sound esoteric, but the reality is that in a deadly confrontation, it takes only a fraction of a second of inattention or distraction — think of the way a pickpocket works, subtly bumping into a victim to momentarily break his or her attention — to take the advantage. There is no need for a spell or a power that incapacitates long term. All that’s necessary is the briefest disruption.

It’s no accident that Shimada was defeated by a master of the jikishinkage ryu. That school concentrated on kiai as a fundamental part of its curriculum. It exists today, and the training is still emphasized.

This ryu defines kiai as a combination of respiration with and without vocalizations, and attitude. To teach the former, students begin with a furibo, a huge, fearsomely heavy club that’s swung in solo exercises to teach muscular and respiratory connections. Later on, the curriculum of jikishinkage ryu takes the student through a succession of four kata sets, each with a different form of kiai. They’re named after the seasons, which have a number of esoteric meanings along with practical physical lessons.

The scrolls of ancient ryu have numerous references to the notion of kiai as a means for dominating an enemy. Kiai no ri is an expression used to describe methods for employing one’s energy to affect another person in a combative sense. Another term is kihaku, which today is often heard in kendo dojo in reference to a “strong spirit.” In older parlance, however, it meant an ability to control circumstances by projecting energy through posture and breathing.

Kiai is one of the many aspects of budo that outwardly seem simple. Look deeper, though, and you’ll find that it’s far from simple.Dave Lowry has written Karate Way since 1986. For more information about his articles and books, visit blackbeltmag.com and type his name into the search box.

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