Berens can still walk down the street without being mobbed by autograph seekers, while Phelps is an internationally-known celebrity who has appeared in advertisements for some of the world's biggest brands. Phelps's fame and instant recognizability have helped him land sponsorships and marketing deals, likely without lifting a finger.
But Berens says athletes such as him -- who excel at lower profile sports yet aren't global icons like Phelps or track star Usain Bolt -- need something to help level the personal branding playing field and increase their visibility and business potential.
Enter social media.
"You're not getting all the TV time, so you have create your own story," Berens told Mashable in an interview. "Social media gives me a chance to do that."
Berens began boosting his social presence, primarily on Twitter and Facebook, about a year ago with consulting help from the new media marketing company Spiracle Media. Since then, he's says he's secured sponsorship deals with BMW, Got Chocolate Milk and TYR. Those deals were made possible by a number of factors, but Berens says he's sure his social media efforts played a crucial role.
On Twitter, he chats with fans frequently, motivates young swimmers and gives followers windows into his day-to-day life. When someone asked last fall if he could defeat his girlfriend, fellow U.S. swimmer Rebecca Soni, in a breaststroke race (her specialty) he posted this video to Facebook. He even recently built his own re-vamped website, tinkering for a few months in WordPress and only calling in outside help a couple of times.
"I think businesses are starting to realize the potential of having social media as one of their main channel," Berens says. "So when they look to sponsor athletes, they want to see how big of a following they have on Twitter and Facebook and how involved they are."
That especially applies to athletes like him. Outside swimming, Berens points to decathlete Bryan Clay and sprinter Sanya Richards-Ross as other under-the-radar Olympians who do stellar jobs leveraging social platforms.
"We only come up once every four years, so the hardest part of our job is to keep people remembering us," Berens says. "Social media has really helped and changed how we can keep the spotlight in the years we aren't in the Olympics."