The original purpose of the English saddle pad was simply to protect the saddle from dirt and sweat, as the panels of the English saddle provided the necessary padding and protection for the horse. Today, English style pads are also used to alter the balance of a saddle and to compensate for fit problems. The best designs absorb shock and minimize fatigue for the horse's back muscles. Saddle pads of various styles or shapes are used with any type of saddle. English saddle pads such as the "riser" pad, which is thicker in the back than the front help with fit issues. Other pads are made with an opening to allow extra room for the withers of the horse, some are shaped to compensate for lordosis or swayback, and many modern "space age" materials are used, such as gel or memory foam to absorb shock, and modern synthetic materials with wicking properties to absorb moisture.