Naps have been shown to benefit almost every aspect of human wellness. The benefits to the body include better heart functioning, hormonal maintenance, and cell repair. They help you live longer, stay more active, and look younger. No organ is as affected by naps (or the lack thereof) as the brain. The benefits result in greater alertness, improved memory retention and creative insight. Napping can make you a faster typist, better dancer or anything else requiring complex and coordinated motor skills. Also, a nap’s effects on mental health include improved mood, lowered stress, and greater psychological balance.

Absolutely. Working long hours, especially the kind of labor that is repetitive and prone to fatigue-related errors, exacts a great toll on money, safety, and health. The more the public learns about the cost of fatigue and the benefits of napping, the more employees will realize they have a right to ask for a nap room at work and employers will realize that allowing them to have one can only benefit their bottom line.

Yes, you can. Benefits of naps can accrue in as little as five minutes. A 20-minute nap can increase alertness, improve physical dexterity, boost stamina, and lower stress. I call this the All-Purpose Nap, because its benefits don’t vary much across the day. So you always know what you’re going to get.

The experience of grogginess, known as Sleep Inertia, can occur after any kind of sleep. The culprit here is Slow Wave Sleep (SWS). This stage is, in terms of brain activity, the polar opposite of wakefulness, when the brain’s electrical activity is busily multitasking and therefore highly desynchronized (operating on many frequencies). During SWS, we have almost completely tuned out the external world and our entire brain rhythm synchronizes into a slow, uniform pattern. Sleep inertia is the lag that occurs while the brain once again recreates those multiple faster frequencies. This period can be minimized by either shortening or lengthening the nap to avoid waking up in SWS. Otherwise, it can be quickly dispelled by physical activity, noise or other sensory stimulation (such as a shower) or, for those who must, with a shot of caffeine.

The first thing to understand is that everyone is physically able to nap. But when working through periods of exhaustion, people employ methods that hinder this natural ability. For instance, in order to stimulate short bursts of energy, we consume caffeine, and high calorie/high fat/high sugar containing foods and drinks. All these interfere with our ability to fall asleep. Securing a safe place to nap where there are no disruptions from ringing phones or passersby will help immensely. Darkening the nap area or wearing an eyeshade stimulates the sleep inducing hormone, melatonin. While people’s tolerance toward temperature varies, it is important to bear in mind that when falling asleep, body temperature drops. Compensate by raising the room temperature or use a blanket.

No, napping does NOT interfere with nighttime sleep, as long as your nap lasts less than three hours and is completed three to four hours prior to your normal bedtime. It is unfortunate that many information sources on sleep hygiene are misinformed about this fact and encourage people to avoid napping if they are having trouble sleeping at night. There is no evidence to support this claim whatsoever.

Naps will never be a replacement for a good night’s sleep. Under extreme circumstances, a strategic napping regimen has been shown to help maintain functioning in the absence of normal nocturnal sleep. For most people most of the time, however, nocturnal sleep is essential.