I’ll be honest: Inner peace, or even increased flexibility, wasn't high on my agenda when I signed up for my first Bikram yoga class. I was looking for some heat. It was February, and I was living in England. It had snowed 15 centimetres one night, and I was a scruffy student who refused to run up my own heating bill. The thought of sitting in a yoga studio, heated to 40 degrees Celsius, sounded like heaven.