I'm 40.
Back in 2000, I had difficulties even climbing regular day-to-day stairs due to knee pain.
I started to train using this thread's main topic challenge, that is 30min on the stairmaster. First I had to put on tapes around my knees to keep some of the pain away.
Now, roughly 9 years after, I still do this challenge. I can climb normal life stairs 2 by 2, I can even squat now (it's new from this year). My routine is very simple, 30 min flat out (anaerobic threshold zone) (hr ~ 170bpm). I loose a kilo a sweet per workout roughly.
To me, stair master allows me for 30 min of dancing. I wear an iPod and ONLY listen to music that provides me with a steady tempo. I then just follow the beat in synch with the music. My play lists are sorted according the the level of intensity I want to reach, Jazzy stuff first ending up with ACDC and Metallica.
It is so fun that even during the summer when I prefer cycling, I still allow myself to train (read dance) indoor listening to my favorite music.
And finally, as a bonus, stair master prepares for decent cycling performances very early in the summer. Although the range of motion is more limited than that of pedaling, the muscle groups and angles involved are quite close especially when you stay proud, don't cheat, remain in an "upright laidback position" holding the front handles for the whole distance
