And to complete the nightmare for his peers, the bionic 'Aqua Man' has a peerless physique to boot. It took 36 years to break Mark Spitz's seven-gold performance and it may take an eternity to eclipse Phelps, for the American has a unique 6'4" weapon, his physique, that is quite a stuff of dreams for others.
While his talent and hard-work are well-documented, Phelps owes his success largely to his amazing physique which boasts of some unique features that leads to the belief that he was born only to swim. He has a long, thin torso that is just what a swimmer aspires for and he weighs 195 pound.
Generally, a man's arm span equals his height but in his case it's 6'7" -- three inches more than his height. Naturally his arms work as powerful propulsive paddles, giving him a clear edge over others.
His lower body, interestingly, is shorter than that of an average man of his height. His relatively short legs result in less drag or resistance. In short, Phelps has an upper body of a 6'8" person but his lower body seems to be of someone who is only 5"10", which also make the perfect plane in water.
His size 14 feet may not dwarf Ian Thrope's size 17 but Phelps' double-jointed ankles allow him to do a ballerina's 'pointe' standing on the tips of the toes. It allows him to whip his feet as if those are flippers and break loose.
His unique constitution also produces less lactic acid than others which means Phelps takes less time to recover. And if he looks indefatigable at times, it's because of the Attention Deficit Hyperactivity Disorder, which he was diagnosed with at the tender age of nine. His daily routine is equally mindboggling.
He consumes 12,000 calorie every day and trains 96 km every week. Naturally it was hardly surprising when Russian swimmer Alexander Sukhorukov went on to describe Phelps as "just a normal person, from a different planet, a planet from a different galaxy."