Before I was only going to the gentle classes. These were slower with less intense poses, and unheated.
More recently I've been going to the actual power classes. They're heated anywhere from 90-100 degrees and wow, do I sweat!! It's a pretty intense workout and I actually still can't do everything. There are some things I have to modify or skip, but I can feel myself and my balance getting stronger each time. I get so excited every time I can do something new, and I'm definitely learning a lot about my body and capabilities.
I also leave yoga feeling so relaxed and much more positive than when I walked in. I know it's corny but I really do feel at peace afterwards! And I get a good workout too. In an hour class, my HRM said I burned just around 500 calories. So I get to use it for myself and for my body!