When you are in bed at night, your body should be totally relaxed and at ease. Your muscles should be loose. Unfortunately, however, many mattresses actually cause your body to tense up and your muscles to stay taut throughout the night, causing you to wake up in the morning feeling sore and uncomfortable. If you already have existing muscle problems, then a poor quality mattress can make them even worse.
With most of the old style spring and foam mattresses, the body has to tense up the muscles so that it the spine stays in the correct shape. This is because they are either too soft or too hard, meaning that they are not ergonomically efficient and your muscles need to correct the poor mattress quality. This will leave you feeling sore in the morning as your muscles have had to work throughout the night.
With a memory foam mattress, your muscles will be able to punch out for the night, because memory foam adjusts itself to fit your body perfectly. No matter how many times you move in the night, the memory foam will readjust and reshape itself, providing total support and ultimate comfort, meaning that you will wake feeling much better.