”Ever since I stopped lifting super heavy and incorporated more low-intensity workouts, not only did I feel so much less bloated throughout the day, but I’m in such a better shape now,” – that’s how Mandana Zarghami says she got rid of what’s being called “cortisol face” in a TikTok video.

Zarghami is not the only wellness influencer encouraging women to ditch lifting weights in favour of low-intensity exercises like walking and pilates. Other women on #GymTok have claimed that walking instead of running avoids facial puffiness associated with “runner’s face”, stopping lifting is what “snatched” their body and quitting HIIT workouts helped them lose weight. While the buzz around “lowering your cortisol” – your body’s stress hormone – is fairly new, the idea that women shouldn’t be engaging in high-intensity or high-impact exercise isn’t. After decades of women fighting for their right to exercise and play sports, why are we still so afraid of becoming swole, puffy, muscly women?

The history of women’s fitness culture is complicated. For much of the 20th century, women were discouraged from engaging in vigorous exercise, being told they were physically limited. Until 1972, women were prohibited from running marathons in the US because they were considered “physiologically incapable”. In America, the 70s changed women’s approach to exercise forever: feminists urged women to embrace their physical strength, women’s magazines promoted exercise to trim your figure, New York City hosted the first all-women’s road race in Central Park and Jane Fonda opened her first workout studio in Beverly Hills.

For a long time, cardio was king and women’s exercise was focused around burning calories, instead of building muscle – “bulky” women being considered “unfeminine”. Until recently, when we reached the point where more people know that strength training is important not only to maintain muscle mass, but also for building bone density (something that becomes even more important with age). “The shift I have seen take hold in a very deep way in popular culture is this move towards women lifting heavy weights,” says Danielle Friedman, author of Let's Get Physical. “Even some of the big gym chains have had to replace cardio equipment with lifting equipment because of this shift.”

But with this shift towards strength training has come a return to the age-old portrayal of women as fragile beings with bodies that can’t handle intense exercise; the latest in the re-purposed myths to keep women focused on maintaining a small, tradionally “feminine” figure. This time, the fear is centred around cortisol. Younger women online have started increasingly worrying about getting cortisol face or even “cortisol belly” from doing the “wrong” workouts. These people encourage low-impact workouts like Pilates was a way to lower your cortisol and tone your body. But this current focus on low-cortisol workouts is, for most people, largely unnecessary.

Alex Rothstein, assistant professor of exercise science at New York Institute of Technology’s School of Health Professions, calls cortisol a “very good hormone” when it’s doing its job properly, with a lot of negative associations. “Cortisol is not inherently a bad thing, but it gets a bad reputation when people live chronically stressful lives,” he says. “When it comes to cortisol and exercise, when you are taking part in an exercise programme that you are trained for, it’s pretty difficult to exercise yourself into negative cortisol levels.”

It’s not bad for your body to produce cortisol; it can be a good thing, but too much stress is what’s bad for you. And that’s not even the exercise itself, but not resting and failing to eat enough food after you work out in order to recover appropriately.

Most often, high cortisol is correlated to the stressors people encounter during the course of an ordinary day (including lack of sleep or being overworked). This means stress-management techniques will lower cortisol levels and regular exercise can actually reduce stress and lower baseline cortisol levels over time. “A controlled cortisol spike [while working out] is actually healthy,” says Rothstein. “It can help build resilience and tolerance, as your body becomes better at handling stress.” (The “stress” being progressive overload.)

As with all things exercise-related, there’s no one-size-fits-all approach. Much of the low-intensity discussion is taking place alongside conversations around women’s hormones, and women’s health is chronically understudied. For people with PCOS, like 26-year-old Jannat, shifting to low-intensity exercise has been beneficial. “I used to run because everyone did that, so I did too,” she says. “I felt awful after, but still booked a boxfit or a Zumba class and even played badminton.”

Over the years, Jannat says her PCOS symptoms worsened, and she became tempted by the idea of a slower, more consistent workout routine after learning about low-cortisol and low-impact workouts in 2019, when she first came across PCOS-friendly trainers on TikTok. “Over time, I think I’ve taken the slowness all the way down and don’t work out anywhere near as much as I used to, but my PCOS symptoms are significantly better,” she says.

Many women, however, feel the best after lifting heavy weights. Casey Johnston, author of A Physical Education and otherwise known as “a swole woman” to her newsletter subscribers, cautions anyone who comes across any one way of exercise being the “answer” for women. “There’s no trick, and the more specific it is, the more likely it’s empty marketing,” she says. “It’s not bad for your body to produce cortisol; it can be a good thing, but too much stress is what’s bad for you. And that’s not even the exercise itself, but not resting and failing to eat enough food after you work out in order to recover appropriately.”

It also feels unsurprising that the idea that women should exercise in a dainty and delicate manner is resurfacing during the current resurgence of ultra-thin ideals, conservative aesthetics and regressive socio-political attitudes. As Naomi Wolf wrote in The Beauty Myth, “A culture fixated on female thinness is not an obsession about female beauty, but an obsession about female obedience.” In the 19th century, the made-up “bicycle face” was used to try to scare off women from cycling and having an independent mode of transportation.

For those who want to start lifting, Johnston recommends starting with the basics: lifting weights that feel a comfortable and appropriate amount of difficult for you, and then building steadily from where you are at. “What makes exercise good for us is the appropriately designed challenge of it, teaching our muscles how to work together,” she says. “Your body is designed for it.”