Well, I've just completed W3 R1 and the thought of jumping from 90 seconds to 3 minutes...yes double... was somewhat disconcerting to say the least. I have completed it but I did find myself getting a bit of a tight chest and a dry cough, but that might be medication... I'm hoping the chest is the body's way of saying
"Oi... what's this exercise lark... you need more oxygen..."...anyway, 1 down, and lovely views.