Is your summer slipping away? We’re here along with Richard Branson, Netflix CEO Reed Hastings, tennis superstar Roger Federer and others to urge you not to let it go without a fight. Take some time off. Not only will you get to have a little fun, but your brain, your work and your manager will thank you.

Limited Vacations

Despite significant scientific evidence that our brains need periods of respite and rejuvenation, more than 40 percent of American workers who received paid time off did not use all of their vacation days in a study by Oxford Economics.

The study suggests a few reasons why people choose not to use their earned vacation:

• 17 percent of managers consider employees who take all of their leave to be less dedicated
• 4 in 10 workers say their heavy workload keeps them from using vacation
• 34 percent say their employer neither encourages nor discourages leave

Why is it then that Branson, Hastings and Federer can all find time to take a break? Branson unplugs on vacation. The entrepreneur told the Nassau Guardian traveling introduces him to people who inspire him in unexpected ways. Hastings uses six weeks of vacation a year at Netflix. He told CNBC he hopes to set a good example for his staff and he often finds a different perspective on things while hiking when he gets away. And Federer, who continues to rack up titles, appears to be using rest as part of a winning strategy. He took six months off before winning the Australian Open and then sat out the clay court season and the French Open before besting everyone at Wimbledon.

What Science Says

Top-tier entrepreneurs, CEOs and athletes understand what many overworked, overtired workers do not. A vacation is both a break and a benefit to our productivity. Neuroscientists tell us focus is a limited resource. Like the rest of our bodies, our brains consume energy. Controlled attention is very hard work, drawing heavily on the prefrontal cortex. Activities such as analyzing, prioritizing, planning and other types of critical thinking are energy guzzlers. As energy supplies dwindle, brains get tired. (For more about this subject read Think Better)

Now, more than ever, we need our brains to do some heavy lifting. More leaders are asking people to be creative at work. Creative thinking and problem solving fuels innovation which leads to growth. Creative work requires many brain states including the need to balance active group work with solitude and individual think time.

It’s one reason why Branson’s employees have unlimited vacation time. And, it’s why he encourages group getaways. “Lots of the best ideas occur when camaraderie and chemistry has built up between employees, and breaks from the office together – even for just a day – can make all the difference,” Branson wrote.

So, don’t let summer get away from you. Take a vacation and give your brain a break. You will return to work refreshed and reenergized. And, you may come back with an innovative idea or a new take on an old problem.