By Phil Gordos
BBC Sport in Athens
Michael Phelps broke two world records in the space of 45 minutes at last year's world championships in Barcelona, an achievement that left the American teenager weak with exhaustion.
Undaunted, the 19-year-old from Baltimore will attempt a feat in Athens that will dwarf those heroic efforts, leaving him a physical wreck but an Olympic and sporting legend.
In attempting to win eight gold medals, thus eclipsing Mark Spitz's tally of seven at the 1972 Games in Munich, Phelps could be forced to swim as many as 17 races in eight days, with some of those races just a few minutes apart.
Madness maybe - and Australian great Ian Thorpe, who won three golds in Sydney, has already labelled the mission an impossible one.
But the Herculean task has certainly captured the imagination and made Phelps the main focus of attention, alongside drugs and security, leading up to start of the 2004 Olympics.
Many expect Phelps, who stands 6ft 4in tall and has size 14 feet, to buckle under the weight of such a monumental burden.
But Simon Breivik, a sports physiologist at the famed Human Performance Centre at Lilleshall, insists it is a burden that can be carried, although he admits Phelps will be pushing his body to the absolute limit.
"Most of his events are one or two minutes long," Breivik told BBC Sport.
"They are horrible ones to be involved in, the equivalent of the 400m and 800m on the track, because they result in major lactic acid build-up.
"That is going to be the main problem Phelps will have to deal with."
Lactic acid is produced following physical exertion and effectively paralyses the muscles once levels get too high.
PHELPS' HERCULEAN EFFORT
200m individual medley
400m individual medley
Given the hectic schedule facing Phelps, the amount of lactates pumping around his body will be huge.
So, once his races are over, his main priority will be to expel them from his body as fast and efficiently as possible.
That means he must resist the temptation to crumple in a heap once he has heaved his aching frame out of the pool.
"The last thing an athlete wants to do is lie down after an event," said Breivik.
"The quicker the blood is pumping around the body, the quicker the lactic acids will be flushed out."
Phelps will probably head for the training pool to recharge his batteries once he has finished an event.
But, somewhat daringly, he could decide to 'take it easy' in some of his early heats in order to revitalise himself.
"For Phelps, it will be about how hard he has to work," said Breivik.
"Michael Johnson (an Olympic champion in both the 200m and 400m) did not have to reach 100% all of the time, so if Phelps can get by the heats and semis at just 80%, he might have a chance to use them as recovery time."
Phelps, who has 'Athens' stitched on the inside of his swimming cap and the Olympic rings tattooed in his right hip, competes in the 200m and 400m medley, 100m and 200m butterfly, 200m freestyle, 4x100m and 4x200m freestyle, and 4x100m medley.
He is favourite to win gold in the 200m and 400m medley as well as the 200m butterfly, but could find compatriot Ian Crocker and Thorpe out-sprinting him in the 100m butterfly and 200m freestyle respectively.
Phelps insists he will be happy to leave Greece with just one gold medal, though he stands to gain $1m from sponsors Speedo if he equals Spitz's record.
Whatever fate awaits him, he will be one of the best-prepared athletes going into the Games.
"His training will have been specific to what he's going to be doing in Athens," said Breivik. "Nothing will come as a surprise."