Swimming , in recreation and sports , the propulsion of the body through water by combined arm and leg motions and the natural flotation of the body. Swimming as an exercise is popular as an all-around body developer and is particularly useful in therapy and as exercise for physically handicapped persons. It is also taught for lifesaving purposes. For activities that involve swimming, see also diving , lifesaving , surfing , synchronized swimming , underwater diving , and water polo. Archaeological and other evidence shows swimming to have been practiced as early as bce in Egypt and thereafter in Assyrian, Greek, and Roman civilizations.