Sleeping Posture

During my mobility class on Thursday, my lecturer casually asked the class this. "I don't think anyone who sleeps in a supine position right?" I expected someone to give a positive response because I do. I would sleep in a supine position with my hands by my side for the whole night without turning around. Well, this habit has to be traced back to ten over years ago when my mom told me that sleeping in that position promotes smooth respiration. It will also not cause much disturbance if anyone is sleeping beside me because I will not move around while sleeping. It also helps to maintain a good posture of the spine. I am not sure where my mom get all this knowledge from but I trust she will never go wrong.