Kaeli Sweigard was devastated when she was dumped by her boyfriend. One of the things they had in common was an interest in combat sports, and Sweigard turned to this shared interest to get her through the breakup. The 30-year-old digital marketer, who lives in Toronto, remembers, “I was so upset and didn’t know what to do, and one of my jiu jitsu mentors told me that I should train every single day that I thought about him. So, that’s what I did.”Sweigard started referring to her jiu jitsu practice as her new boyfriend. Her body changed, but so did her attitude. “I became more fit after the breakup once I started taking training more seriously," she says. "Even just the mental shift of taking training more seriously and relying on it as a positive focus in my life changed the nature of my training.”Sweigard’s response to the breakup—getting fitter, happier, and more productive—was generally beneficial. And this is the kind of narrative that’s often applied to a "revenge body," a tabloid term popularized in the last decade with reference to celebrities.The archetypal example, of course, is a member of another excruciatingly famous family. Khloé Kardashian has long been seen as the poor-rich-girl of the Kardashian clan, due mainly to being slightly less svelte than her sisters. Following her split with basketball player Lamar Odom, she poured energy into slimming down. And her “revenge”—against her ex-husband, her sisters, and her viewers—was made complete in January 2017, the month after her divorce was finalized, with the premiere of her weight-loss show Revenge Body with Khloé Kardashian. The woman famous for her revenge body was now peddling her ability to shepherd others through the same process.The work of Lora Park, a psychology professor at the University at Buffalo, offers some clues as to who’s most likely to seek out this specific type of physical transformation. Park and colleagues have extensively researched self-esteem and the degree to which this is based on appearance and relationship status. Park explains, “those with low self-esteem who based self-worth on others’ approval were more concerned about appearing attractive and physically fit.”One advantage of seeking out validation from others based on attractiveness is that this is less risky emotionally. As Park says, “Appearing attractive to others doesn’t necessarily require interacting directly with others. Thus, one can protect their self-esteem and avoid potential rejection by focusing on their appearance, rather than focusing on their internal qualities like being warm, caring, or kind.”Psychologists like to talk about intrinsic enjoyment versus introjected self-regulation—or, in layman's terms, doing something just because you’re into it versus because your self-worth hinges on succeeding at it. This motivation matters: “This is what contingencies of self-worth represent. When people stake their self-worth in a domain, like their appearance or on being in a relationship, then they feel like they have to look good—and not look bad—or have to have a boyfriend or girlfriend in order to feel like they have worth and value as a human being," Park says. "That’s a lot of pressure, especially since people can’t always succeed in the areas in which they stake their self-worth.”Park’s work also suggests that having high "appearance-based rejection sensitivity" (anxious worry about being rejected based on looks) and "relationship contingency of self-worth" (a sense of self-worth that depends on a significant other) may affect one's motivation to seek out a revenge body, particularly for someone who’s been dumped. People with these vulnerabilities “are most at risk of experiencing negative consequences, and subsequently, are the most motivated to repair their self-esteem following [a] threat.” These kinds of vulnerabilities are also heightened in the social media era of constant photo sharing.This doesn’t mean that every case of post-breakup fitness is psychologically harmful. For one thing, it’s possible to move from external to internal motivations. And those external improvements to self-esteem can be especially helpful when the breakup is still raw. “We do get reinforced for losing weight and getting ourselves fixed up," says Amy Flowers, a licensed clinical psychologist specializing in body image. "A lot of people are going to say, gosh, you look great. So that kind of reinforces that behavior."There are also some common-sense reasons that someone might cope with a relationship breakdown by hitting the gym. A breakup can feel disorienting. Working on a revenge body, Flowers says, is partly a control issue. It may be an illusion of control, but “it’s a way of feeling like I’m doing something. I’m not just going to sit here and languish; I’m going to do something to try to improve myself.”And, of course, newly single people often have a lot of time on their hands. “Number one, it gives you something to do. Get out of the house, go to the gym, don’t isolate,” Flowers says. "There’s a desire to increase attractiveness, especially for women, and possibly to attract a new partner. But newly abundant time and energy also means that a breakup is a good time to decide who you are and what you want, Flowers adds.In Sweigard’s case, she’d been wanting to ramp up her martial arts training. The catalyst was her breakup, but it turned into a lifestyle, as documented on her jiu jitsu blog. As Park and her colleagues have pointed out, the pursuit of self-esteem can be costly. Shiny exemplars of successful revenge bodies may be more likely to persist in Instagram feeds, but it’s useful to ask about what’s motivating these folks.Whatever the motivation, it’s clear that the concept of the revenge body is very twenty-first century. As Park says, “this notion of 'revenge bodies' makes sense because appearance is the currency of our times in terms of a relatively quick way to attain status, approval, and boost self-esteem.”*This article was originally published on Vice by Christine Ro and can be found here.