Are your employees getting enough sleep? Likely not.

Chances are they're sleeping less than the seven to nine hours recommended by the National Sleep Foundation — averaging 6.8 hours per night, according to Gallup. But there may be something you can do about it.

A new study published in the journal Sleep Health shows that workers will likely get more sleep when their employers play a more active role in ensuring they're better rested — especially when they offer flexible work policies.

The researchers studied 800 employees, encouraging 474 of them to be flexible about where and when they work, while putting in the same number of hours as those not offered flexibility. Additionally, researchers provided sleep hygiene education to those workers’ employers to encourage them to better support their employees' personal lives.

After a year, the researchers found those employees were averaging eight more minutes of sleep per night — totaling almost an additional hour each week.

"We showed that an intervention focused on changing the workplace culture could increase the measured amount of sleep employees obtain, as well as their perception that their sleep was more sufficient," according to Orfeu M. Buxton, associate professor of biobehavioral health at Pennsylvania State University, one of the study’s authors.

Jeff Mintzer, deputy director for behavioral health services division for Federal Occupational Health, said the study results are consistent with what he's seen in his own research, and shows why it’s important that employers take care of their workers — their "most valuable resource."

"You give your car a tune up, so why is there a disconnect with how you would offer maintenance or care for your workforce?" Mintzer said.

A lack of sleep costs the U.S. $63 billion each year in lost productivity, according to the National Sleep Foundation. In addition, 29 percent of workers report falling asleep or becoming very sleepy at work.

So giving employees more control over their time — such as when and where they spend their working hours, whether it’s at home, a coffee shop or elsewhere — could be one of the keys to fixing that.

"A person having the sense they have some control over how they manage their time could give them the assurance they need to gain sleep and gain a better perspective over their health,” Mintzer said. "If they have a flexible schedule, they can manage the sleep they need."

Even so, other companies are encouraging employees to sleep on the actual job, Mintzer said, giving a nod to the relatively new — but growing — concept of "nap rooms."

It could help increase overall productivity by giving employees a much-needed break during the workday — a simple accommodation that could allow them to be more productive for the remainder of the day, he said.

Even a 20 minute nap can boost workers’ alertness and improve overall performance, according to the National Sleep Foundation.

While only a handful of companies now employ the napping concept, it could catch on. Mintzer said he believes a cultural shift about the idea of sleeping at work might first be needed — particularly a more healthy focus on what it means to be productive.

"How do we normalize that it’s super productive to take a nap?" he said. "It’s so needed that our culture shift to understand being productive, and that it’s not having someone with their eyeballs taped open so it looks like they’re awake."

Although it’s ultimately up to employees to manage their own sleep habits and health, is it perhaps time for employers to look at what else can be done?

"The more innovative companies get it," Mintzer said. "The success is part of their culture."