There is a science behind using your voice as a weapon, or kiaijutsu, as Japanese masters call it. It is the projection of ki, or internal energy, and manifests itself in the Kiai, or “martial arts shout”. With this energy you penetrate, like an arrow, your opponent’s spirit.
The Kiai Startles Your Opponent
There is great power in sound. It is your best weapon on the street, I always tell my students. As your attacker attempts to grab you, let out a blood-curdling scream in his face. It will startle even the most hardened of criminals, even if only for a second—long enough for you to strike or run. It puts the attacker on the defensive straight away.
The Kiai Makes You Strong
The shout helps with any heavy exertion. This is why you hear power lifters and tennis players do it. It also serves to “amp you up”, or get primed for combat.
The Kiai Protects You
The exhalation of air from the lungs, combined with tensing of the abdominal muscles when shouting, strengthens and protects the torso from strikes or kicks. It also prevents the habit of nervously holding the breath while engaging in combat.
A loud yell will also attract the attention of bystanders, who may be able to come to your assistance, if needed.
The Kiai Must be Practiced
Practice the Kiai in during training as often as possible. It should come from the gut or diaphragm, not the throat, much like breathing in yoga or playing a musical instrument. It is a skill worth mastering. Some say that masters of the art are actually able to freeze multiple opponents, push people backwards, or even knock people over with this skill. What is your experience with the karate kiai?