We’re heading into summer — time to kick back and relax, right? Not for a lot of us. More than half of U.S. workers don’t use all of their vacation days, even though taking time to rest and rejuvenate is key to productivity.

People recognize that they need this time for themselves — in a survey of full-time workers in the U.S. 45 percent say that paid time off for mental health days would help them beat burnout. But they struggle to break away from the incessant demands of the office.

45 percent of full-time workers say that paid time off for mental health days would help them beat burnout.

Even a single day off can feel like a break, and summer is an ideal time to get a day to yourself on the calendar.

WHY WE NEED TO RECHARGE

When you work without breaks you’re busy, but not necessarily productive. “It’s important to have opportunities to rest and reflect and recharge. It’s a mistake to think that more hours worked equals more productivity,” says Leah Weiss, Ph.D., author of “How We Work” and a Stanford Graduate School of Business lecturer. “Our bodies and minds are not meant to push constantly — even elite athletes need to have rest as part of the process of becoming stronger.”

Tara O’Sullivan, chief creative officer at Skillsoft, compares time off to sleep. “Sleep is when everything repairs itself and allows the body to recover. You need to allow your thought process to do the same,” she says.

Our bodies and minds are not meant to push constantly — even elite athletes need to have rest as part of the process of becoming stronger.

Sacrifice your need to recharge and ultimately you sacrifice your health. “You’re not doing anybody any favors if you give up your mental health for a job. The healthiest people are the ones who take time for themselves and their families,” says Katherine Nelson, an instructor in the human resource management department at Temple University’s Fox School of Business in Philadelphia.

5 WAYS TO MAKE IT HAPPEN

The demands of work will always be there. But with planning you can push them away for a day.

Start with your calendar. Does your work cycle have slower and busier periods? Pick a slower day and you’ll be more likely to stick with your plan. Make a commitment. If you think you’ll be tempted to cancel your day off and come into work, plan something you won’t want to give up. Sign up for a seminar, buy tickets to a concert or sporting event, book a spa day or make plans with a friend. Enlist your colleagues. Ask them what they think they’ll need when you’re out, so you can prepare. Set parameters — maybe they will call your cell phone if something truly critical comes up. That way you free yourself from checking email and texts. Send a strong out-of-office message. Provide email addresses and phone numbers of colleagues people can contact while you’re out. Chris Dyer, author of “The Power of Company Culture,” recommends asking people to resend their messages after your return day, and deleting all the emails that came in while you were out. Really. Trust your team. The world won’t end if you take a day off. “We all think we’re indispensable, but none of us are. If you got hit by a truck tomorrow your boss would figure out a workaround,” Nelson says.

YOU HAVE YOUR DAY OFF. NOW WHAT?

It might be tempting to just keep the day wide open, but that’s a mistake. You won’t be rejuvenated if you feel like you wasted the day watching Netflix. And don’t tackle a to-do list, either. This is not a day for oil changes and dentist appointments. Think about what you need, and design your day ahead of time.

Ask yourself what kinds of things you would do if you had six months to live.

Know what makes you feel better. For a lot of people, top choices are spending time outdoors, movement and social connection. Plan activities where you get “lost in the flow,” says Kristina Hallett, Ph.D., a board-certified clinical psychologist and author of “Own Best Friend: Eight Steps to a Life of Purpose, Passion, and Ease.”

Learning can be restorative, so if learning isn’t part of your job try using this day for expanding your brain. Practice an instrument, take an art lesson or attend a workshop.

Not sure what you would like to do? “Ask yourself what kinds of things you would do if you had six months to live,” says Karissa Thacker, Ph.D., author of “The Art of Authenticity.” Is there a scaled-down version of those things you could do in a free day? If travel is on your list, see a nearby city or attraction. If it’s spending time with your kids, consider pulling them out of school for a trip to the zoo or a ball game.

“One day off here and there can be a fantastic reminder of life outside of work. There is always another perspective. You just have to move to see it,” O’Sullivan says.

TAKE YOUR CAREER TO THE NEXT LEVEL

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