Thank you. I found that rhythm by accident... it just felt natural. I didn't work on any particular breathing pattern on hills, it just happened from the first time I climbed a tough hill. I haven't even counted the pedal strokes with each breath -- I'm estimating it's 2-3 pedal strokes, but that number varies from hill to hill. Anyway, try taking deeper breaths to fill your lungs, you'll find your own natural rhythm.