Researchers and health experts have long stressed the importance of taking time off.

"Vacations are really important to recover from our always-on work culture," says Ashley Whillans, assistant professor of business administration at Harvard Business School and author of "Time Smart." "They help us come back to work more refreshed, more creative, more energized, feeling more positive."

And though the immediate benefits are clear, it turns out making them a habit from the beginning of your career onward is critical both for your health and success down the line.

In the U.S., especially as it pertains to those generations who've been in the workforce for several decades, it's "a lot of people with a backlog of burnout," says Ludmila Praslova, professor of psychology at Vanguard University of Southern California. "Like, a lifetime of not having vacations."

To avoid this buildup of burnout, which can cause physical and emotional exhaustion, and possibly even depression, you have to keep up "vacation hygiene through your lifetime," she says.

'There are people who can take a day trip and be very refreshed'

There isn't necessarily an ideal amount of vacation for each person.

"There are people who can take a day trip and be very refreshed," says Praslova. "There are people who can take a week or eight days and be very refreshed." The point is, as soon as you enter the workforce, figure out how to get that time off throughout the year.

If you're not sure what could best serve to rejuvenate you, "I would recommend one or two longer vacations and several long weekends evenly distributed throughout the year," says Jessica de Bloom, an associate professor at the University of Groningen in the Netherlands who's researched the various benefits of vacations.

This will both give you an opportunity to see how you feel after each one, and maximize the benefits of your time off in general. The point is to "create a lifestyle early on that will prevent accruing" vacation deficit, says Praslova.

'What do I need to set me up for success?'

Of course, with no federal policy on vacations in the U.S., not every worker gets PTO.

"There are so many people that are holding down two, three jobs, doing gigs on the side in between work, have a job because it provides health insurance for families," says Octavia Goredema, career coach and author of "Prep, Push, Pivot." Sometimes, "we don't have the autonomy or the ability to pick and choose how we work."

But, she says to ask yourself, when it comes to what you can control about your routine, "what are the non-negotiables?"

Time off is critical for people's health and well-being. To ensure you get it in some form, maybe you can ask to move around shifts or take off a couple for a long weekend. Or maybe you can talk to colleagues about how you can cover shifts for them so there's more flexibility down the line.

The point is, in approaching every gig, ask yourself, "What do I need to set me up for success?"

And know that taking time off should be high on the priority list.

Check out:

Harvard professor: How to get your team to take vacations and return 'more refreshed, more creative, more energized'

'Don't wait for the perfect moment': 7 bosses share their advice for young people on taking PTO

Don't read vacation emails, keep your return date a secret and other tips for hacking your PTO

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