Most office workers sit for 10 hours a day, but if they sign up for the Tough Mudder, a military-style obstacle course, they’ll certainly be on their feet—running through live electrical wires. They’ll also be on their hands, swinging from treacherous-looking monkey bars, and on their stomachs, crawling through the mud. And yet, millions of people have paid about $100 each for the privilege.

Rebecca Scott, a lecturer at Cardiff Business School in Wales, sought to explore this paradox when she was working on her PhD dissertation. Initially focused on the psychology of hedonism and pleasure, she was interviewing competitive offshore yacht racers in Sydney, Australia, when one day a skipper mused to her, “Why do people want to sit on a boat for days and get pummeled with weather?” as she recalled. That, she decided, was a more interesting question: Why would comfortable Westerners want to pay for physical pain?

For a new study, Scott and her co-authors, Julien Cayla at Nanyang Business School in Singapore and Bernard Cova at the Kedge Business School in France, participated in Tough Mudders, interviewed 26 participants, and read online forums created by the Tough Mudder community to try to understand what motivates people to run these races.

In an interview, Scott said the Tough Mudder’s electric shocks and ice water are more of a “gimmicky pain”—not comparable to something like climbing Mt. Everest. “You have short bouts of pain, like smacking into muddy water,” she said. However, what’s notable about the race is that the people who run it tend to be “in lifestyles that are very comfortable and easy.” And though the pain is short-lived, it’s real: At one event Scott took part in, emergency workers were “scooping people off the floor and into ambulances” after the electric-wire obstacle, she said.

As she interviewed participants, Scott noticed most of them worked desk jobs in industries like engineering and PR. Even the participant who was a nurse said she was sedentary for most of the day. In their conversations with Scott and each other, the participants emphasized how painful it was to train for and compete in the Mudder—and how rewarding that pain felt in the end.  Here’s how a man named James described the “Arctic Enema” obstacle, in which participants slide into a dumpster full of ice water, on his blog: “I can’t breathe. My legs aren’t working. My head is going to explode! My arms are too cold to drag me out. That was horrendous.”

As the event wore on, many participants described dissociating from their thoughts, as though in a zen state of unity with their mud-caked bodies. A man named Mike said, “I wasn’t feeling bad, but I wasn’t feeling good, I don’t know how to explain it, I wasn’t in shock, I wasn’t worried, I wasn’t in pain, but I wasn’t all there, I was a bit rattled.”

Scott and her colleagues argue that “Mike’s experience of not being ‘all there’ is consistent with past research arguing that extreme pain obliterates ‘the contents of consciousness.’” The intense pain helps them to forget, temporarily, the hyper-mental concerns of their daily lives as cubicle drones.

The participant named James exhibited that mentality in saying, after the Mudder was over, “Ready for our road trip back to the normality of screaming children, laptops and [the grocery store] Tescos … I wonder if we could just stay here and do it all again.”

The authors note that Tough Mudders are not the only way people try to escape the the cognitive overload of white-collar work:

These stories of overworked individuals wanting to escape the tedium of office life are consistent with other phenomena, such as hyperstressed financial workers in London paying to spend their lunch breaks floating inside darkened isolation tanks where they achieve a dream-like state. What is distinctive about Tough Mudder, though, is the way participants achieve this escape through pain rather than isolation, sensory overload rather than sensory deprivation.

Indeed, as anyone who has begrudgingly trained for a marathon on battered knees or iced themselves after Crossfit might know, the fitness industry offers any number of extreme ways to temporarily short-circuit your brain.

Scott argues that, in a way, Tough Mudders and other painful forms of exercise allow people to “rediscover” their physical bodies, as revealed in participant comments like, “I hurt in places I didn’t even know existed.” The study authors write:

Phenomenological rediscovery of the body offsets the physical malaise and corporeal absence they experience in their everyday life. Experience organizations like Tough Mudder are selling a ritualized shattering of the self that is especially attractive to the worn-out “cognitariat,” knowledge workers who are not only working jobs of limited physicality but also feel the burden of constant self-actualization.

Trying to get through a grueling obstacle course, in other words, can be a welcome respite from trying to write a sensitive email. Before Tough Mudders came along, psychologists observed this phenomenon of extreme escapism with binge drinking, binge eating, clubbing, and other weekend-warrior adventures. “People sometimes find it burdensome and aversive to be aware of themselves,” as psychologists Roy Baumeister and Todd Heatherton wrote in a study on binge eating, “so they seek to escape.” But because it’s difficult to simply stop dwelling on your work-related problems, it helps if there’s a greased quarter-pipe to distract you.

There are other ways to interpret the authors’ findings. Jana Costas, a professor at the European University Viadrina in Germany, said the participants might have simply craved extreme exercise because their work hours are also extreme. “Rather than simply regarding this turn as an escape from work, I believe it is the continuation of a certain ethos found in contemporary workplaces and capitalism at large, namely the need to prove and show one’s resilience, strength, drive, as well as ability to move out of the comfort zone, [and] challenge oneself,” she said in an email.

The irony, as Scott and her co-authors point out, is that even as white-collar workers pay for painful escapes like these, Americans with blue-collar backgrounds are dying from an epidemic of chronic pain. “In working-class contexts pain is often concealed for fear of exposing one’s weaknesses,” the authors write. “In contrast, our research features consumers who are willing to pay significant money for the pain that others simply cannot avoid.”

Scott’s work doesn’t explicitly come out against Tough Mudders and the like, but it does suggest that perhaps white-collar workers ought to rethink their tendency to bounce between extreme inactivity and the most extreme activities of all. Her work suggests sitting all day in a stultifying office can make people feel so dehumanized that, like the characters in Fight Club, they have to run a dangerous race just to feel alive again.

“We are part of a society that pushes comfort, comfort, comfort,” Scott said. “Everything in [a] pharmacy is meant to stop pain, whether it’s shoe insoles or itch creams. We’re saying that actually, that’s not necessarily a good thing. We have everything set up to make us so comfortable, and that almost numbs the body.”