so i sing a long to a vocal warm up cd ( its the zen of screaming but for the warmups its entirely singing) and the excersizers are supposed to be done like "sing the part, breathe, listen to a note, sing the next part, breathe, etc"

after im done singing the part i still have plenty of breath left but it feels like its "old air" if that makes any sense. Should i be breathing out and then breathing in or should i try to use the air for the next part?
just like being an athlete, get as much oxygen in as you can.
Cream fan club member #11.