Read this in a Newsweek article:
5. Wind-Relieving] <b>. Thought fiber was the only natural remedy for expelling excess gas? Think again: this series of yoga postures assumed in asana-based classes assists air in exiting your digestive tract—in a room full of people. The motions involve lying flat on your back and pulling your left, right or both knees into your tensed stomach, squeezing out the stale air or, in instructor's lingo, engaging your abdominal region to assist with elimination. The poses are also said to enhance supine strength and flexibility, making them optimal for those with both bad backs and Metamucil in their pantries (read: old people). "It could certainly be helpful with some individuals in terms of [their] low backs," says Bryant.
Very interesting. I believe it too. I can't even count the nights I've climbed into bed, gotten onto my left side, all covered up and cozy and then need the bathroom, again. It never fails. Certain prone positions bring on either gas or bm's for me.
I've never taken a yoga class but if I ever do, I will take the very back row and by the door. In case the class starts anything up, if you know what I mean!