well, I'm going to have to disagree with that. Just goes to show everyone's different.

I find that I breathe much more efficiently both running and cycling when it's synced to my cadence. Chi Running definitely recommends syncing one's breath as a way of maintaining body awareness. Swimming, obviously everyone has to sync, like it or not. If you feel you're breathing too fast, try adding a pedal stroke - in one, out two; in two, out two; in two, out three; or whatever.