And, as a linguistic aside, "kokyu" can mean much more than "breath." Simplistically, the "ko" in this term basically means, "to invite," and "kyuu" means "to suck." Interestingly enough, one of the definitions you can find of "kokyuu" in addition to "breath; respiration" is "knack; trick; secret (of doing something)." It's also used in phrases such as, "kokyuu ga au" (with "au," once again, using the same character as "ai" in "aikido") which basically means that two people's relationship/rhythm are very well matched.

-- Jun