Yet it is possible to be successful while working normal hours. Indeed, some people who work reasonable hours in unreasonable fields say their schedules aren’t just about maintaining their personal lives. They view keeping a lid on their hours as a competitive advantage—something that’s helped them be successful in the first place.

It’s less radical than it sounds. First, few people actually work extreme hours, even if they think they do. One study comparing people’s estimated workweeks with time diaries found that people claiming to work 75-plus hours per week were off by about 25 hours. Also, working 40 hours doesn’t mean working from 9 a.m. to 5 p.m. Most people take breaks for lunch, coffee, and so forth, or have personal activities (e.g. dentist appointments) that intrude into work hours on occasion. You can work at night, and on weekends, and still just hit 40.

In any case, working 40-ish hours provides space for a lot if allocated wisely. Manoush Zomorodi, host of WNYC’s Note to Self, tries to strike a balance between putting in the hours necessary to succeed at work and spending time with her young children. “We have a team that has to be pretty social to make what we’re making,” she says. “For the creative process, if you’re in the zone, you can’t break that up.” Her solution is what she calls “chunking.” She works very long days, until 9 p.m. or 10 p.m. on Monday and Tuesday, so the team has long hours together to brainstorm. On Wednesday, she goes to a writer’s room for silent, focused work. Thursday and Friday are much shorter days, so she can pick up her kids from school and spend time with them.

Family is often the big reason people choose to limit their hours, but any major interest outside of work can provide a nudge. “If you want work-life balance, you’ve got to have a life,” says Jon Gillon, co-founder and CEO of Roost, a sharing-economy platform that lets people rent out storage space and parking spots. He and his girlfriend attend a wide variety of live music shows, and he skis, snowboards, and practices yoga. To make time for these things, Gillon has developed efficiency techniques that go beyond the usual small stakes suggestions (such as sending shorter emails). “I close quickly,” he says. “A lot of people put a lot of time into follow-up work, which I try not to.” If he finds someone he likes, he will hire the person in the first meeting. When meeting with investors, he will ask for a decision to avoid dragging the process out. And the key thing: “I’m probably the dumbest guy on my team, and that’s why I’m able to work normal hours,” he says. “I find people to do stuff better than me.”

Working 40-ish hours means missing out on some face time, but people who are committed to working reasonable hours tend not to be obsessed with perceptions. Bonnie Crater, CEO of marketing company Full Circle Insights and a Silicon Valley veteran, says, “My whole life I’ve probably worked typically 40-50 hours a week.” There have been busy times, but even when she was 26 and working at Oracle, she would visit a nearby ice rink in the middle of the mornings on Tuesdays and Thursdays to get a speed skating workout in. “I just did it,” she says.

The key reason? “I was a much better performer if I had good balance in my life,” she says. Indeed, people who work reasonable hours in unreasonable fields say that while having time for personal priorities is great, the business benefits are often just as critical. “Our philosophy is that the rest is as important as the work,” says Crater, who claims to chase people out of the office around 5 p.m. “We work in an industry where business creativity is at a premium,” and “in order to be the most creative, your brain has to be not tired.” She asks people about their hobbies in job interviews—to ensure they have them. “We like to encourage a maximum of 50 hours,” she says. “It’s working for us.”

Joanna Norwood, a physician who practices in a poor section of Scotland, works very hard during the hours she’s on. “Some people have such bad lives you couldn’t make it up,” she says. “You have to be completely on your game all day, completely concentrating on the one person in your room, making lots of decisions in 10 minutes, and then doing it again, many times over.”

That’s why a lot of physicians get burned out. It is hard to maintain empathy for that last patient, particularly if you’re covering evening clinic hours, as Norwood sometimes does. So she doesn’t work on Tuesdays. “I think it makes me better to have the time off,” she says. The break lets her come in the next day fresh. “I’d like to be working for a long time,” she says, so “you have to have some kind of boundaries to achieve that.”