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Do you often feel tired and fatigued during the day without a nap? Do you think daily naps are a necessity to function properly? If your answer to both questions is “yes,” you may be on to something.
People—unlike other mammals—are monophasic sleepers, which means that our day is divided into two phases: active time during the day and sleep time at night. Yet 85 percent of other mammalian species sleep for a short time during the day. Can short naps change the way we feel? And can they have a positive effect our productivity during the day?
In Spain, the siesta time is deeply rooted in the country’s culture. Shops and businesses close between 2 p.m. and 5 p.m., and bars and restaurants close between 4 p.m. and 8 or 9 p.m. The tradition of napping in countries with a hot climate—like Spain, Italy and Greece—comes from the idea that physical workers should avoid the sun’s strong midday rays. A quick rest in the afternoon is believed to restore one’s energy level, allowing for more productivity for the remainder of the day. 
What Are the Different Types of Naps?
The types of naps we take can be divided into three categories:
- Planned napping, also called preparatory napping, is a type of nap where you get to bed before you become tired or sleepy. This technique can help prepare you to stay up later at night. For example, if you’re getting ready for a party and know you’ll be staying up late, you may decide to take a nap even though you don’t feel tired. 
- Habitual napping, as the name indicates, means making a habit out of taking naps. Habitual napping occurs regularly during the same time each day. Older adults and young children are more likely to practice habitual napping. In countries that observe siesta, adults often take a traditional short nap after having a lunch.
- Emergency napping occurs when a person cannot continue with his or her normal activities. An emergency nap is commonly used among truck drivers and people with long commutes. It also may help sometimes due to constant lack of sleep at night, emergency napping can occur due to feelings of fatigue and malaise.
How Long Is a Good Nap?
According to sleep.org, the ideal length for a nap is about 20 minutes. The benefits of napping for that duration include better mood, more energy, and improved alertness. Naps also have been shown to improve cognitive functioning.  Twenty minutes of napping is considered an energized nap because you reach only the lightest stage of non-REM sleep, which makes it easier to go back to normal activities after a napping session.
Late-afternoon naps aren’t usually recommended—especially for seniors—because it can interfere with nighttime sleep. As you get older, you tend to sleep more lightly, so napping during the day can be helpful with catching up on the lost sleep, as long as it’s not too late during the day or too long.
DID YOU KNOW?
Naps can help you learn new skills. According to PubMed, habitual nappers performed better at reading tasks than people who do not take naps regularly. Research supports the fact that naps can increase productivity at work.
Companies like Google and NASA, for example, recognize their employees’ needs. Since 1990, napping has become common practice among NASA astronauts and pilots, while Google’s headquarters in Mountain View, Calif., provides its employees with special rooms with futuristic‑looking lounge chairs and soothing sounds in the background designed for napping.
Negative Effects of Napping
According to the European Research Society, too long of a nap is associated with decreased psychomotor speed, verbal memory, and worsened verbal fluency. Naps longer than 30 minutes can lead to sleep inertia. Sleep inertia symptoms include a groggy feeling, disorientation, and tiredness.
Depending on the timing and duration, long naps also interrupt nocturnal sleep. People who like to nap for longer than an hour during the day are at increased risk of getting diabetes, according to telegraph.com. And according to a study conducted by scientists from the University of Tokyo, taking regular daytime naps of more than an hour increases by 46 percent the risk of developing diabetes in people who reported severe daytime fatigue. Taking a short nap does not increase this risk.