Léon Marchand is a French swimmer. He is the World record holder in the long course 200 and 400 metres individual medley, and in the short course 200 metres individual medley; the Olympic record holder in the 200 metres butterfly, the 200 metres breaststroke, the 200 and 400 metres individual medley; and the French record holder in the long course 400 metres individual medley, 200 metres individual medley, 200 metres butterfly and 200 metres breaststroke, and in the short course 400 metres individual medley, 200 metres individual medley, 100 metres individual medley and 200 metres breaststroke. From Wikipedia