Incredible how people overlook such a simple and effective workout. Im lucky to live in a 33rd floor building, so every time Im too lazy to go out to exercise, I just climb the stairs! I do the whole 33 floors than I do 17 more to end at 50. At the end I feel like im overheating and run to the shower. Mostly aerobic but with a nice anareobic touch. I found out I like to do it barefoot, since i feel it work the muscles more, with cushioned shoes the "proper technique" is throw out of the window and you end up tiring your joints and ligaments more than the muscles.