World Sleep Day | Can’t sleep during the afternoon? Here’s everything you want to know about naps!

Today is World Sleep Day. Many people are concerned about sleep at night, but today we are going to talk about naps. Are you unable to sleep during the afternoon? In fact, this question can have several meanings, such as whether you are suitable for naps? Are you unable to sleep during the afternoon nap? This article will answer many questions about naps!

01 Characteristics of “nap”

Literally, "siesta" is a short nap at noon. At the physiological level, it is significantly different from sleep at night in two aspects.

First, naps are highly personal. One-year-old children usually take a nap in the morning and afternoon. When they are two years old, the number of naps begins to decrease. By the age of six, many children are no longer used to taking naps. Resting at night is highly related to the biological clock and can be regarded as an instinct.

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Secondly, naps are generally shorter. Normally, a sleep cycle is about 90 minutes. When we sleep at night, we go through multiple sleep cycles. We start with light sleep, gradually enter dreams, and then start another sleep cycle until we wake up in the morning. However, clear dreams usually do not appear during naps.

Sleep cycle (Source: created by the author)

These two differences show that naps have their own characteristics. They can be used as a supplement to night rest, but they cannot completely replace the latter.

02Who needs a nap?

So, who needs extra sleep? There are three types of people who should seriously consider taking an afternoon nap.

First, those who are seriously sleep deprived . The consequences of long-term sleep deprivation are not listed here one by one; the harm of a sleepless night is often ignored by people. Studies have shown that the impact of a sleepless night on the human body is equivalent to drinking alcohol, which will interfere with reaction speed, affect judgment, and even cause mild reversible memory problems.

For this situation, the best way is of course to "treat the root cause" and improve the time and quality of sleep at night. If this is not possible for the time being, taking a nap can "treat the symptoms" - a 2015 study pointed out that taking a nap can reduce the impact of insufficient sleep to a certain extent .

Second, mental workers . Mental work is inseparable from reading, analysis, and memory, and often requires dealing with interpersonal relationships.

Naps are good for both activities: on the one hand, naps can increase long-term memory, allowing us to remember more clearly and accurately; on the other hand, naps are equivalent to pressing the "reset button" for psychological activities. After a nap, people will be more positive and more patient in dealing with interpersonal relationships.

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Third, patients with chronic diseases . Hypertension, diabetes, and hyperlipidemia often occur together, which has a great impact on the quality of life and even the length of life; in terms of prevention and treatment, people need long-term cooperation.

In recent years, many studies have found that moderate naps are very beneficial for preventing the three highs and reducing the incidence of cardiovascular diseases.

The benefits of taking a nap (Source: author’s own)

03Who is not suitable for taking a nap?

Are there people who are not suitable for taking naps? Yes, there are, and they can be roughly divided into two categories.

First, those who cannot adapt to napping . As mentioned before, napping is very personal. If you are really not used to it, don't force yourself.

The second is insomniacs . If insomniacs take a nap at noon, it may be more difficult to fall asleep at night. Therefore, it is generally not recommended to take a nap.

For these two types of people, you may wish to take advantage of the lunch break to bask in the sun or do some light or moderate intensity exercise, which can not only temporarily relax the body and mind, but also be good for sleep at night.

Tips to improve sleep (Source: author's own)

04How can I sleep well?

If you want to sleep well at night, you need to pay attention to the time, posture and environment. The key points of taking a nap are also these three aspects.

In terms of time , the best time is between 2pm and 4pm, and the length should be controlled within 15 to 30 minutes . The former is when humans are most tired during the day; as for the latter, if the nap time is too short, the effect is not obvious, and if it is too long, it may have side effects.

In terms of posture , lying flat is the best. Considering the objective conditions, a chair with firm support and a flat back is also a good choice. Some people are used to lying down for naps. In fact, this posture is not good for the brain, eyes, cervical spine, arms and other parts. If there is really no other way, you can buy a pillow and hug it when you sleep. This can raise the neck, relax the arms, and improve the oxygen supply to the brain.

As for the environment , it is best to turn off the lights and draw the curtains . If this is not possible, using an eye mask to block out the light is also OK. Moreover, although it is already spring, it is still not warm. It is best to prepare a thin blanket to avoid catching a cold.

In addition, since naps mostly happen in the office, there are other factors to consider. For example, before going to bed, you can hand over work, save and organize relevant information. If you press the delete key while sleeping, it may be a tragedy; for example, set a gentle alarm clock to wake yourself up without disturbing others.

The process of taking a nap (Source: self-made by the author)

Nap alarm clock

Some scholars suggest drinking a cup of coffee before taking a nap. It takes about 25 minutes for coffee to take effect, which can be used as an alarm clock. However, the acceptance of coffee varies from person to person, so readers should choose according to their own situation.

Conclusion

If you see some fragmented images or feel like you are falling from a height during your nap, it means you have successfully entered a light sleep. Your brainpower and mood in the afternoon will definitely be better than usual.

In short, although napping is a small thing, it can bring a strong sense of happiness. As long as we can master the rules, it can be used to our advantage.

References

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Author: Zhao Yanchang, a popular science author

Reviewer: Peng Zhiping, Director of the Information Science Department of the China Sleep Research Society

Produced by: Science Popularization China

Produced by: China Science and Technology Press Co., Ltd., China Science and Technology Publishing House (Beijing) Digital Media Co., Ltd.