Many of those U.S. hopefuls train right here in Southern California, including the women’s water polo team captain and three-time Olympian, Brenda Villa.
Villa's 5-foot-4 frame is compact. Her hands are tiny. She's the only Mexican-American on the Olympic water polo team, and at 32, she's also one of the the oldest.
"No I'm definitely not your typical water polo player, but I think because I grew up playing against boys and that just made me a smarter player because I couldn't be as fast or as strong as them," Villa said.
Villa first jumped into the pool when she was six years old. Her mother Rosa, who emigrated from Mexico to the U.S. in the 1970s, never learned how to swim and wanted her daughter to get an early start in the water.
Within two years Villa was begging to play water polo on her older brother’s team. At first Rosa Villa was concerned about her 8-year-old daughter playing water polo with the boys.
"In her eyes she's like, ‘You're my daughter, this is kind of a rough sport, the boys are playing it,’” Villa said. “‘What are you going to do in this sport?’ But once I started we haven't looked back."
Villa grew up in Commerce, Calif., an industrial city that's home to about 12,000 residents and a slew of big businesses. Companies like General Mills and the Commerce Casino give back to the community by supporting the local parks and recreation department.
Brenda's father Ines never imagined those practices would lead to the Olympics.
"I think that we never imagined that we would be there. When we learned that the sport would be Olympic we didn't think that we would go … that she would go. It was a surprise and we had the opportunity to go with her." Ines Villa said.
Women’s water polo became an official Olympic sport in 2000 at the Sydney summer games. Villa was only 20 years old at the time, and already had a full scholarship to play water polo at Stanford after leading the boys water polo team in high school.
After graduating from Stanford, Villa was at the top of her game, but couldn’t make a living as a professional athlete in the states. Instead, Villa decided to split her time playing professionally in Italy for half the year and then coming back to practice with the U.S. National Team for the other half.
Villa is the most decorated women’s water polo in the world, but she's still missing one thing — a gold medal.
"I know I'm at the end of my career as an elite water polo player, so you train hard and you just want to be in that final game playing the best water polo you that you can,” Villa said.
There’s no clear favorite for the gold this summer. Australia, Russia and Italy are competitive, but the U.S. is looking strong after winning several major international competitions in the last few years.
In the fall, Villa will move up to Northern California to coach water polo at a private all-girls school. She's also spearheading Project 20-20 -- a program that will teach water sports to low-income kids in East Palo Alto and Menlo Park.
"I think for me this sport has given me so much and I think there's a lot of kids out there that could benefit from just playing the sport,” Villa said. “They may not be Olympians, but I think the team dynamic, the work ethic that you're taught can just help in life in general."
Correction: An earlier version of this story had the incorrect city
for the 2000 Olympics. Thanks to our commenters for pointing out the