Swimming stroke

Human swimming typically consists of repeating a specific body motion or swimming stroke to propel the body forward. There are many kinds of strokes, each defining a different swimming style or crawl. In high school, collegiate, and Olympic swimming, there are two undulating strokes (breaststroke and butterfly stroke) and two alternating strokes (front crawl and backstroke). Most strokes involve rhythmic and coordinated movements of all major body parts — torso, arms, legs, hands, feet, and head. Breathing typically must be synchronized with the strokes, too. It is possible, however, to swim by moving only legs without arms or only arms without legs; such strokes may be used for special purposes, for training or exercise, or by amputees and paralytics, such as Paralympians.