I got lucky yesterday and the stairmonster was occupied when I got to the gym. So I did my normal stairs, 3 flights from top to bottom. One rep is up and down, did 40 reps or 120 flights in 30 minutes on the nose with #50 pack. I am 6' 185 and will be 51 come Labor Day. It was taxing for sure but not as bad as the machine for 30.