HIYA!

Have you ever wondered about that Karate yell—“HIYA!”

In martial arts and self-defense you’re encouraged to Kiai or Qia (pronounced keeyah) which means “energy,” ”life giving force,” “concentrate,” or “spirit yell” depending on the language referenced. In other words you’re encouraged to yell to help focus, startle the opponent, help you breathe, or alert others to your plight depending on the circumstance.*

You can read more here:
http://www.martialinfo.com/article.asp?gbfspn=74&fb_source=message