A firm mattress for aiding back troubles is one of the most popular misconceptions. Medium-firmness beds help men and women with back issues more often than the their rigid counterparts, according to a Spanish test completed in 2003. There was another study done in 2008 that compared hard mattresses and Talalay latex mattresses and waterbeds. The conclusion saw increased back pains and restless nights for the men and women who used the firm mattress and not the latex foam mattresses.