...When Hysmon [of Elis] was still a boy he was attacked by a flux in his muscles, and it was in order that by hard exercise he might be a healthy man free from disease that he practised the pentathlon. So his training was also to make him win famous victories in the games. Pausanias, Description of Greece , 6.3.9

Glaucus, the son of Demylus, was a farmer. "The ploughshare one day fell out of the plough, and he fitted it into its place, using his hand as a hammer; Demylus happened to be a spectator of his son's performance, and thereupon brought him to Olympia to box. There Glaucus, inexperienced in boxing, was wounded... and he was thought to be fainting from the number of his wounds. Then they say that his father called out to him, 'Son, the plough touch.' So he dealt his opponent a more violent blow which... brought him the victory. " Pausanias, Description of Greece , 6.10.1