It went by really fast! I like that it changed a lot and I didn't have to think, the instructor always told me what to do (what incline, etc). I did this class yesterday for the first time and oh boy, I am SO sore today.
I love that it changes each time so it is always a new challenge. Even if I am a little sore, or under the weather, I can still burn quite a few calories and just take it a bit easier. This class works well for all fitness levels!