Breathe in when raising the arms; breathe out when lowering them.
Interesting. This is something I'm working on. Although, I have no idea if we're talking about it in the same way. I'm using the breath (the inhale) as a tool to help inititiate internal pressure, that powers
the raising of the arms. And I'm not talking about the oxygen.
The exhale and gravity lowers the arms (kokyu anyone?). These are not overt cycles. My goal is a very calm or imperceptible breath, and to always
use the legs.
Oh well, give me a few more years ...