I did my 30 minutes of stair sprints while lifting weights. I like how much it makes me sweat and how much water I need to drink. That's one of the ways I measure how intense a work-out is for me. Since I go on the stairs at the gym, it's a bit like being in a character in a video game trying not to bump into texters. People who happen to be using the stairs (not specifically for exercise but in order to get somewhere) while texting have no sense at all of what is going on around them. You should see the look on their face when they see they have narrowly missed impact by a red faced fat woman wearing a fanny pack and hoisting weights wildly
