Mel is a 45-year-old marketing manager for a comic book company in Los Angeles, and a self-proclaimed “nerd.” Until recently, he’d never been able to stay on a workout regimen for very long. Nine months ago, he weighed 320 pounds, and by his own admission, was “lethargic and slow. I would lose my breath just by walking up a flight of stairs on the subway.”

But all of that changed this year. Today, he says he’s 273 pounds, and losing more weight every week.

How did he do it? He started doing workouts inspired by one of his passions, The Lord of the Rings.

The workout is called “Eye of Sauron,” and it was created by Andrew Deutsch, the head coach and owner of Nerdstrong Gym in North Hollywood, California.

Deutsch started Nerdstrong in his garage in 2013, when he became the personal fitness trainer for the dungeon master at his Dungeons & Dragons group. Since then, he’s created workouts designed to appeal to people more interested in Dr. Who and Star Wars than kettlebells.

What’s involved in the Eye of Sauron workout? It goes like this: “In The Lord of the Rings, the bad guy is represented by a giant eye—The Eye of Sauron—and the eye has a beam that sweeps across the land and the characters have to get down to avoid being seen by it,” Deutsch said.

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Deutsch continues: “So in the workout, every three minutes the Eye of Sauron sweeps across the gym and everyone has to hold a plank position for a minute until it passes.”

“Also, Frodo and Sam had to climb a lot of stairs, so our members do stepups with a weight on them. The ring has a heavy burden to it, so we have them have to carry a weight the entire workout to represent that.”

It’s not really the workout that’s exceptional. What’s exceptional is how it has enticed fitness-averse guys like Mel to return to the gym, week after week, and as a result, they’re getting serious results.

Mel said that prior to discovering Nerdstrong, he never felt comfortable at other gyms. “I can’t quite put a finger on it, but I felt like an outsider,” he claims. “The worst part was to be using an exercise machine and feeling like I’m not using it properly, and other people watching, judging, and laughing at me.”

Anyone who regularly goes to a gym will probably wince at that explanation. It makes most gyms sound like a 1980s teen sex comedy, with “jocks” bullying the weaker members, giving wedgies to anyone they perceive as a nerd.

The reality, in most cases, is nothing like that. People are focused on their own workouts, not what you’re doing. They honestly couldn’t care less. Just wipe off the machine after you’re done, and that’s as much as they’re interested.

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But that doesn’t make a place like Nerdstrong any less necessary. Because it’s not the reality that matters, it’s that guys like Mel feel that way.

Heather Hausenblas, Ph.D., a Jacksonville University health and fitness researcher, believes that Mel and others might suffer from social physique anxiety. It’s what “people experience when they are in social situations and fear that people are evaluating their physique in a negative way,” she said. “My research, as well as others, shows that people who experience high SPA are less likely to work out in social situations because of this fear that people are evaluating them.”

That anxiety is reduced in a gym like Nerdstrong, where they’re surrounded by like-minded people, who share their same interests and fitness levels. It fixes a problem that may only exist in a person’s mind, but is nevertheless real enough to impact his life. After all, mental hurdles can be huge obstacles.

Nerdstrong isn’t the only gym trying to create a safe space for people who normally avoid gyms. Mark Fisher Fitness in New York City takes a similar approach, catering to Broadway buffs, nerds, geeks, and unicorn lovers. As owner and founder Fisher describes it, his gym is “like the isle of Misfit toys.”

Like Nerdstrong, Fisher offers themed workouts inspired by pop culture fictions that his members enjoy, which include movies like Point Break, The Big Lebowski, and Back to the Future, as well as ninja and superhero workouts.

It’s also a place to, well, let’s say let your freak flag fly.

“We make it a space that’s safe for someone who wants to dress as an S&M unicorn pirate,” explains Fisher.

He adds, “People who don’t like the gym are typically people who had a complicated relationship with athleticism and their bodies throughout middle school and high school. They all share a dislike of a traditional gym culture that unites them and motivates them and keeps them coming back.”

Coming back really is the key. Anybody can walk into a gym once and give it a try. But it’s finding the excitement that makes you want to come back again and again and again; that’s what truly matters. And that’s what these alternative gyms are tapping into.

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Our brains are hard-wired to be around people who look and talk and sound like us, said Barbara Markway, Ph.D. a psychologist and author of books like Dying of Embarrassment: Help for Social Anxiety and Phobia. “From an evolutionary point of view, this makes sense. To stay with the pack, to fit in, meant survival.”

Staying with the pack has certainly helped Mel. During his workouts, he’s surrounded by people who share his enthusiasm for superhero films, Star Wars, and Game of Thrones. But to hear him talk, you'd think he'd spent his life at the gym.

"I’ve reached and then topped personal records in bench press, deadlifts, and other exercises," he said, with a palpable excitement. “I’ve reached a level of self-confidence I’ve never had before. I used to shy away from photos; now, I take lots of them!”