In general, a percussion instrument is defined as an instrument made of sonorous material that is struck or shaken. Its vibration produces sounds of either definite or indefinite pitch. The pitch is determined through the tautness of the stretched material for indefinite pitch instruments or by the size of the objects in most definite pitch instruments. The repetitive movement of playing a percussion instrument combined with the endurance it requires can be a great workout. Playing percussion instruments can also improve coordination and motor skills, and the required simultaneous movement improves ambidexterity.