I did the 30 day Bikram challenge in January of this year, and was disappointed because I actually gained weight (about 3-4 pounds). I thought for certain the strenuous daily activity would help me drop weight, but it didn’t. I was sad about that.
It could be that the yoga series strenghtened my muscles and that actually added weight to my body. I was also drinking a lot of water.
My shape did change a bit, and I felt firmer, but I was hoping to burn fat off too. I don’t know if that happened.