Kiai is a technique of what martial artist call the “Spirit Shout or Yell”. When you Kia on a punch or block an increase in energy is delivered to the target. When one is breaking bricks or boards the function of this simple yell becomes very apparent. It is also found that the energy increases with focus, thought and intent, seeing the energy flow through your body to the target. You will also find that when one is struck by someone else and the Kiai is used, the attacked individual is able to adsorb the energy of the strike more easily. Why, you are releasing energy at the same time energy is being sent into your system. So Kia becomes important in not only striking but being able to defend.
I was taught a Kiai system by one of my Aikido teachers which relates specific sounds to specific directions;
Ey! – straight forward e.g. punch
U! – inward e.g. pulling in whilst striking like at the beginning of Jon’s Heian Nidan – this would be a compound Kiai; UEy!
Ee! – downward e.g. when throwing or groin strikes.
Ah! – expanding outward e.g. knife hand/soto uke.
Oh! – upward e.g. rising block.
I have worked with theses for years and it is second nature now.
I don’t know if the matching of the sounds to the movement really makes a difference in terms of strength or wether it seems to now simply because of psychological association.
However, it might be interesting to experiment with different Kiai sounds and see if it seems to make a difference to the feel of your movement.
I continue measure my kia spirit during any training session. I find that by continually focusing on maintaining a strong kia, my techniques seem to be stronger in deliver. I would like to know if any other students have similar experiences in keeping a strong kia during training sessions.