Surfing is often celebrated as a bastion for free spirits and self-expression. But ask former pro surfer Cori Schumacher about that and the story she tells will break your heart.

Schumacher is a talented surfer who won the Women’s World Longboard championship three times. To compete as a professional required a hefty commitment of time and focus, but whenever Schumacher paddled out, she had to work even harder to hide the secret she kept.

It may sound implausible that being an openly gay surfer is taboo, yet it remains one of surfing’s biggest secrets.

"When I paddled out, I had more of my attention diverted toward making sure that I was nice to people, smiling at people, flirtatious so that I didn’t come off as gay," Schumacher said. "And probably the only place that I really felt comfortable was when I wasn’t around a group of people in the water and I was just on a wave."

Schumacher’s story is one of many at the heart of a new documentary, "Out in the Line-Up," that will screen at this week’s Honolulu Rainbow Film Festival.

The film, directed by Australian Ian Thomson, explores what it means to be a gay surfer and the growing global community that’s used social media to unite.

In the film, former Australian champion surfer David Wakefield and Thomas Castets, who founded an online community for gay surfers, travel the world to better understand the situation. They found surfers who were bullied and beaten, heard stories of surfers who took their own life, and interviewed surfers who feared their lucrative sponsorships and professional careers would wipe out if they came out.

"Most gay people feel that they have to hide their sexuality for fear of rejection," Castets said in an email from Sydney. "I believe that living in fear holds you back in life — perhaps even as a surfer. Many of the top surfers we spoke to said they started surfing better when they were no longer hiding part of themselves."

When they approached the Association of Surfing Professionals for an interview, though, the governing body of the surfing world denied their request, Castets said. And some straight surfers told the filmmakers that people would think they were gay if they granted an interview for the documentary, Castets said.

"I think this points to the fact that most people haven’t thought about it because it is such a taboo," said Castets, whose website, www.gaysurfers.net, has more than 5,000 members. "Most haven’t thought about how hard it would be to be gay in many surf communities."

He said gays and lesbians are more likely to suffer from depression and anxiety than straight people, "in large part because of such feelings of isolation."

Schumacher, now 37, came out publicly in 2010. In a phone call from her home in Southern California, she said acceptance of gay rights in the United States has improved dramatically since 2008. But there’s more work to do.

"It is still an uncomfortable subject in surfing, but it is a little more of an easy conversation to have," she said. "The fact that most surfers don’t actually think about it is indicative of how much it’s been kept quiet and silenced and that people don’t want to talk about it."

The film is a big step toward further acceptance, Schumacher said.

"People sharing their stories — it is so much more difficult to hate a human being than it is to hate a stereotype. When you are looking into the eyes of a human being, it is harder to hate them," she said.

"Out in the Line-Up" will screen at 5:30 p.m. Friday at the Doris Duke Theatre. For more information about the film festival, visit www.hglcf.org.

AND that’s a wrap …

Mike Gordon is the Star-Advertiser’s film and television writer. Read his Outtakes Online blog at honolulupulse.com. Reach him at 529-4803 or email mgordon@staradvertiser.com.