With 14 Olympic gold medals to his name Phelps is without doubt a superhuman when in the water. Eight of those medals have come from Beijing alone where he dominated the Butterfly and Freestyle swimming events.

Now he can rotate his feet 15 degrees further than an average human being. His wrists, elbows and knees are double jointed. And his heart pumps 30 litres per minute, again twice that of an average man.