One of the most widely recognized characteristics of Karate practice is the use of shouting. Although most people realize that Bruce Lee’s unnatural, drawn-out, high-pitched noises were meant more as movie spectacle than anything else, it is true that shouts are an integral part of regular karate practice.

But is this shout simply a shout? Or is there some deeper meaning? Does it symbolize something? Or is it just a display of machismo?

Let us begin by analyzing the kanji (Japanese/Chinese characters) used to write the term.

Ki means “energy.”*

Ai means “meet” or “join” or “come together.”

The term therefore means “joining energy” or something to that effect. It is the channeling or focusing of energy, bringing together all the energy one can muster. Usually, this concentration of energy is combined with an audible expulsion of breath. The actual shout is not necessary in kiai, but it is a usual bi-product of it. There is such a thing as a “silent kiai.” But for most I would suggest making a sound if the instructor asks for a kiai, to be sure not to be unintentionally offensive.

The kiai has several possible uses. I will review its four main uses below:

To scare or startle the opponent/attacker
Both in a dojo/tournament situation and in self-defense, it is fairly obvious that it is usually to one’s advantage to be able to startle someone. In this use of the kiai, the audible portion might not occur simultaneously with the kiai, or even with a technique, for that matter.

To get attention (in a self-defense situation)
Whether or not an attacker is scared off or startled by the defender’s shout, in a self-defense situation, others may hear the sound and come to see what is happening. Many would-be attackers are afraid of getting caught and if they think someone is going to find out about what they are doing, they may stop the attack. Of course self-defense scenarios can be complicated and I am not implying that the shouting will help in every situation. However, getting attention with your voice is a possible outcome.

To provide spirit
Whether or not one ends up startling the opponent/attacker, shouting can give the defender (the person emitting the kiai) spirit. When combined with a startled attacker, the defender’s spirit may rise even more.

To coordinate breathing and muscular contraction
Breathing out as you shout (try shouting while breathing in for an interesting exercise) is more condusive to contraction of the muscles of the torso. This contraction of the torso muscles is a desired state when delivering many attacks, as it can help ‘connect’ various body parts for increased overall momentum transfer. It can also aid in making a more resilient target for any potential counterattacks from the opponent/attacker. For more on breathing, please see my March 2000 article.

Some beginners misunderstand and think that the kiai is supposed to be the sound “kiai.” Any sound can be used as the audible representation of the kiai. Usually, the best sounds are monosyllabic. Depending on what you want to accomplish with the shout, it could be longer or shorter, end in a vowel or consonant. For a sharp, abruptly-stopping technique, a short sound, ending with a consonant, might be ideal. For a motion that is intended to pass through a target, it may be better to let the sound trail off with a vowel ending. The way you emit sound has a relationship with your breathing, which should be considered when trying to match a sound to a technique. During your own private practice, I would suggest experimenting with several different sounds for a variety of techniques to hear and feel the differences in breathing, muscular tension and spirit.

As with many other subjects covered in my articles, I would suggest asking your instructor for feedback regarding your kiai. There is only so much one can learn about a subject such as this through the written word alone.

Copyright © 2022, Jon Keeling (originally published February 2001)