The suits are certainly a factor. How much of a factor is a subject of much debate. Speedo's LZR Racer, which was developed in cooperation with NASA and designed to reduce drag, has received considerable attention for its laser-bonded seams and its ability to increase oxygen intake by 5%.
It also compresses a swimmer's body so much, it often takes an athlete 30 minutes or more to put it on -- one inch at a time. Zimbabwe's Kristy Coventry said putting on the suit is so painful on her fingers, she has to put band-aids on them all the time. But she wouldn't dare wear anything else. Why give your competitors an edge?
"I think everyone is wearing the suit now, so we're on kind of a level playing field," said Coventry, who set a world record in the semifinals of the 100-meter backstroke. "Technology in all sports keep advancing, and I think they will as technology grows. I think sports kind of have to keep up with that technology. It's a great suit. I love it."
Of the 36 medals awarded thus far in China, 33 of them have gone to athletes wearing the LZR Racer. Since the suit made its debut in February, it's been used to break 57 world records. (Many, such as Phelps' record in the 400-meter individual medley, have been lowered multiple times.) Most of the swimmers, however, believe it's unfair to simply chalk it up to the suits.
"You can win without a suit or with one," said Aaron Piersol, who switched to Speedo this year after wearing Nike for much of his career. "Hopefully our sport stays that way. Certainly no one wants to lose to a suit. We swim the race against the athletes next to us, not the technology."
The new pools, which are deeper and now feature 10 lanes so the two outside lanes can remain empty, have also played a role because turbulence has been reduced. It's easier to swim fast in smooth water, and waves dissipate quickly into high-tech gutters. The pool in Beijing is also three meters deep, whereas most pools in previous Olympics were only two meters deep. That means a swimmer such as Phelps, who gets a turbo boost off the wall on his turns, can dive deeper and stay under water longer. According to his coach Bob Bowman, that helps him do his dolphin kick for a longer period of time, and helps him go faster.