Gold Mind

Along with these ministrations, USA Swimming has also employed fluid-mechanics experts to examine how water is most efficiently shunted over the human body. Meanwhile, Speedo has invested millions in the development of the LZR Racer, an unprecedented, swing-for-the-fences bodysuit that has been credited with more than 50 world-record swims since its debut in February.

Tinkering with the angle at which the swimmers' fingers enter the water; computing the flow mechanics of an alternate head angle; charting glycogen levels; encasing the body in polyurethane: If it seems that nothing is being left to chance, that's because, really, nothing is. Though few things make Phelps crankier than asking him to tell you his goals (which are famously secret and known only to himself and Bowman), even the sloppiest back-of-the-envelope calculation makes it clear that by declaring eight golds as his ultimate challenge—a feat that was quickly moving from possible to probable after Phelps smashed yet another world record in the 200 freestyle on Tuesday morning—we are thinking small. This is Phelps's third Olympiad, and he's only 23. He could lose one or two or even three races in Beijing and still walk away with more career gold medals than not only Mark Spitz but also anyone, ever—and that's before you consider London in 2012, in which Phelps has said he would like to compete. "I just want to do things no one else has done," he says.

And if he doesn't realize all of his goals, whatever they might be? "He's the best ever in this sport," says Weber-Gale, his relay teammate. "Regardless of what happens."

Follow Michael Phelps's quest for gold medal history, race by race, at SI.com/Olympics.