No matter how they package it, these businesses aren’t just selling physical activity; they’re providing people with a way to adhere to expectations that the industry itself helped set. “Exercise, and especially public exercise, came to signify mental, emotional, and even spiritual health and virtue,” Marc Stern, a historian at Bentley University, wrote in 2008. In return for the effort, gym-goers attain the type of body that proves their virtue to all who see them.

That these physical standards are difficult to achieve is the point. “We live in a culture in which being industrious is highly, highly valorized,” Petrzela, the New School professor, who is working on a book about fitness’s place in American culture, told me. “Many people want to be perceived as people who value exercise, because it shows they’re committed to self-improvement, and to hard work.” Above and beyond movement itself, part of the satisfaction of gym-going comes from performing those values around other people who share them, and from achieving what that community regards as success.

This psychological cycle of work and reward means that there’s all the more to lose when gyms go dark. If you spent hours every week in Pilates class or carefully monitoring your protein macros in pursuit of gains, where do the energy and care put into those rituals go when you’re asked to stay home? “Those kinds of things really do matter to people,” Stern told me. “Many people view the gym as that space where they’re able to demonstrate their own willingness to try to control their life, and it’s especially important in a time when that kind of control is really absent.” For some people, exercising alone in their living room doesn’t grant that same sense of role-fulfillment. Proving something to others is often a big part of proving it to yourself, and that’s difficult to do when no one else can see you.