Question: "My yoga instructor says it's better to turn the air conditioner off during class so our muscles will stay warm, but I'm afraid the sweaty environment just breeds germs. Who's right?"
Answer: Actually, you both have a point. Warmer temperatures will allow bacteria to multiply, says Jack Brown, PhD, a professor of molecular biosciences at the University of Kansas in Lawrence. However, if no one sneezes near you, and if you keep your hands away from your face and wash and dry your hands thoroughly immediately following class, you're not likely to get ill, he says.
As far as your muscles are concerned, the room doesn't need to be super-warm in order for your muscles to stretch — they will be warmed by the increased blood flow brought about by your yoga practice, says Mitch Whaley, PhD, chairman of the School of Exercise at Ball State University in Muncie, Indiana.