I hadn't even arrived at my first hot yoga class before I started sweating. All day at work my fearful anticipation had been building. How hot was "hot"? Would the room smell? Would we have to get naked? As it was, clothing was minimal. Men went topless; women stuck with stretch shorts and sports bras. There's a good reason: the studio is heated to 37 degrees Celsius. There was no stench though - the polished wooden floors prevented it from lingering. The 75-minute session began with breathing exercises and some standing postures, which are based on Bikram yoga poses.

Instructor Lou Cassella then led the Power Vinyasa segment, a fast- paced, flowing sequence, no pauses in between exercises. Sweat and serenity became a tricky mix. The beach towel covering my yoga mat stopped me slipping in my own sweat, but my Downward Dog looked more like a Dead Dog and the perspiration half-blinded me. Despite guzzling water I felt dizzy and had to stop several times.The gentle stretches that rounded off the class were a welcome relief. It took me 10 minutes just to recover enough to stand up.