Koroleva's partner, Mary Killman, swam competitively before she switched to synchronized swimming. Killman was also on the U.S. synchronized team that features eight members performing in the water at the same time, but it failed to qualify for the London Olympics.

She says synchronized swimming is a very aesthetic sport, and that how you look in a number of areas - even in your swimsuit - are important.

"They judge how high out of the water you are. They judge how fast you can move," she explains. "And on the artistic side, it's how does it match the music. Do you look like you're enjoying it?"

Koroleva says perfecting routines takes long, hard hours of practice.

"People ask, 'How long can you hold your breath for?' Or you know, 'How do you do that?' And it's just a lot of training," she says. "You know you start when you're little, just doing a lap under water. And you can't even make the whole lap because your lungs can't handle it. But over time, you get used to it. So it's just a lot of years of training and repetition."

Mariya Koroleva and Mary Killman hope that all of their hard work pays off at the London Olympics. In their final competition before the Summer Games, they won the gold medal at the Swiss Open on July 1.