A thick mattress for aiding back pains is one of the most common myths. Medium-firmness beds help men and women with back pain more often than the their innerspring counterparts, according to a Spanish analysis conducted in 2003. There was another study completed in 2008 that studied hard mattresses and Talalay latex mattresses and waterbeds. The result was increased back pains and restless nights for the men and women who used the firm mattress and not the latex foam mattresses.