All naps are not created equal. Nap length, accessories, environment, and your lifestyle all matter.

Some of the most well-known businesses and organizations in the world — think Google, Nike, NASA — have realized that napping can help boost productivity. That’s why many are investing in nap pods and transforming conference spaces into sleep rooms.

“The idea that napping is only for preschoolers is simply not true,” said Raj Dasgupta, MD, a professor of pulmonary and sleep medicine at the University of Southern California.

In actuality, power naps offer a myriad of possible health benefits, from helping to relieve stress to increasing alertness.

But how, exactly, should you go about adding power naps to your daily schedule? Check out our guide to power naps below to find out how you can successfully catch a bit more shut-eye.

According to Camilo A. Ruiz, DO, medical director at Choice Physicians Sleep Center in South Florida, a good nap allows for the recovery of brain function, memory consolidation, the ridding of toxins that build up throughout the day, and a burst of energy.

“There’s a drive for us to seek sleep at some point during the day,” he said. As this process builds up, it overcomes you, putting you to sleep at night.

“The idea with napping is that we can reset that trigger and hopefully be able to function at a higher level,” Ruiz added.

Research suggests that in sleep-deprived people, naps increase alertness, work performance, and learning ability, added Dasgupta. A small 2015 study suggests that power naps can even help boost immune function.

Not everyone needs to nap. For instance, people with insomnia shouldn’t nap, explained Michael Breus, PhD, a board certified sleep specialist based in Manhattan Beach, California. If you have insomnia, daytime naps can wind up making you feel like you don’t need to sleep as much at night, potentially worsening your condition.

“If you’re getting good restorative sleep and functioning well during the day, you likely don’t need to nap,” added Dasgupta.

But here’s the catch: More than one-third of adults in the United States don’t get the recommended 7 hours of sleep per night. So, you might not be sleeping as well as you think.

“There are plenty of people who say, ‘I think I sleep fine,’ but if you did a sleep study on them, they’d have underlying sleep issues,” said Ruiz.

If you notice that your productivity starts to wane, that you can’t process information as quickly as you could in the morning, or that you regularly daydream or feel like there’s a “fog” you can’t work through, you could benefit from a power nap, Ruiz added.

While there are plenty of other energizing stimulants out there, such as coffee, nothing is better than sleep, explained Ruiz. Sleep is truly restorative for both your brain and your body.

It also helps fight back against sleep debt, which can contribute to the progression of chronic disease and mood disorders as well as low energy and low productivity.

“We sleep for a reason — to rest and restore,” said Ruiz. “Coffee and other stimulants are short-lived, unlike a true nap, which can provide you with an extra 2 or 3 hours of alertness. [That’s] more than you can get from coffee.”

To perfect the power nap, you have to perfect your timing. An often-cited 1995 study by NASA found that a 26-minute nap was the sweet spot for quick shut-eye, improving alertness by 54% and performance by 34%.

According to a 2010 research review, 5 to 30 minutes is the ideal range to reap benefits without leaving you feeling groggy when waking up. And don’t forget to set an alarm so you don’t go beyond that window.

Here’s why a nap’s length matters: Sleep happens in cycles. A normal cycle starts with lighter stages of sleep called non-rapid eye movement (NREM) sleep and eventually hits a much deeper stage of sleep called REM sleep.

This process repeats while you sleep, with each cycle lasting about 90 minutes. Deep REM sleep is crucial for overall health and well-being — it’s when your body works to restore energy, increase blood supply to muscles, and promote growth and repair of tissues and bones.

But when you nap, you want to avoid it.

That’s because if you wake up from REM sleep, you might experience sleep inertia, which leaves you feeling groggy and disoriented. If, however, you nap for only 20 minutes, you’ll likely wake up in lighter stages of sleep and thus feel refreshed.

But beyond how long you sleep, there are other ways to make a power nap more effective. Start with these four techniques.

Create the perfect nap zone

A dark, cool, quiet room is ideal, said Dasgupta. If you can’t control the light, temperature, or noise on your own, Dasgupta suggested wearing a sleep mask, taking off extra layers like sweaters, and considering using a white noise app.

You’ll also want to avoid disruptions, which might mean turning your phone off for a few minutes, silencing notifications, or putting an old-school “do not disturb” sign on your door.

Time it well

Between 1 p.m. and 3 p.m., your body temperature drops and there’s an increase in your level of the sleep hormone melatonin. This combination makes you sleepy, which is why this is a good time to nap, explained Breus.

It’s usually best not to nap after 3 or 4 p.m., since it might negatively affect the quality of your sleep that night. But if you’re a night owl, a quick nap at 5 or 6 p.m. can help you power through the early evening, added Ruiz.

Ruiz also said that napping an hour or two before something important — like a public speaking event or a demanding task at work — can promote alertness and mental engagement.

Consider caffeine

The idea of sipping a coffee before you go to bed may sound counterintuitive, but since caffeine takes 20 to 30 minutes to kick in, consuming a bit of the stimulant right before you nap allows you to wake up with an added burst of alertness, explained Dasgupta.

If you’re a shift worker, make naps routine

If you’re a doctor, nurse, or firefighter or you work in another job that calls for hours outside the average 9-to-5 window, chances are that your sleep may be disrupted. Taking advantage of downtime for power napping can help make your sleep more regular.

“If you’re consistently sleep-deprived, napping on a schedule can help your body become somewhat used to it,” said Dasgupta. You’ll grow to anticipate a nap between 1:20 and 1:40 p.m., for example, and be able to reboot your body and brain while also logging more shut-eye on a regular basis.