Sometimes referred to as visco-elastic foam, memory foam has become an extremely popular alternative to traditional innerspring mattresses. It incorporates technology originally developed by NASA to protect astronauts against the extreme force exerted on them by increased gravity during takeoff.
Memory foam became famous for its ability to mold to the imprint made by your body. It provides an even amount of support, so pressure points like your shoulders and hips receive less strain because the foam conforms very closely to the shape of your body. Your weight is therefore spread over a greater area.
Memory foam is made of a type of high-density polyurethane foam which contains billions of tiny air-filled cells that act like balloons. The cells are sensitive to weight and temperature and decompress under pressure, especially if the compression is accompanied by heat. The sensation when you lie down on a memory foam mattress is a unique melting effect due to the cells directly underneath your body releasing their air and conforming to the shape of your body. When you get up, the cells inflate with air slowly, resulting in a delayed recovery time. Memory foam therefore got its name because it is very slow to return to its original shape, thereby "remembering" the shape and contours of your body.
While well-balanced support, long lifespan and allergen resistance are key benefits of memory foam mattresses, it is important to note they also tend to retain heat and are somewhat challenging to change positions on them.
The amount of space you have is usually the most important factor when purchasing a mattress. It's recommended to have the largest bed your space will allow. Your bed should be wide enough and long enough so that each sleeper can rest comfortably in their space. Try to purchase a bed that is at least four inches longer than the height of the tallest sleeper.