According to Dr. Scott Bautch, a Wisconsin chiropractor interviewed by Mary Duenwald in The New York Times, “Your spine should look the same when you’re lying down as it does when you're standing up. That means that when you are lying on your side, your shoulders and hips should sink into the mattress, while your waist is supported”. A too-firm mattress, whether made of foam, springs or air chambers, may not allow enough give for that to happen. Choice.com’s excellent article explains that a hard mattress may tax back and neck muscles, which will have to work harder to keep your spine straight. The information source goes here.
http://www.consumersearch.com/www/house_and_home/mattress-reviews/review.html
http://www.consumersearch.com/www/house_and_home/mattress-reviews/review.html
