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How to improve sleep quality in winter


“Do you find it difficult to fall asleep in the winter because your body is cold?” People who are sensitive to cold temperatures may particularly be fighting cold hands and feet in bed.
I will tell you how to fall asleep naturally in the cold winter and how to improve the quality of your sleep.

Don’t wear socks to bed

Some people who are sensitive to cold may have a habit of wearing socks to bed because their feet are cold and they can’t sleep. However, this is not recommended.
When you sleep, heat is released from your hands and feet, and the core temperature inside your body drops slightly. This will make you sleepy, so it is important not to interfere with the drop in core body temperature; in other words, not to interfere with the release of heat from your hands and feet.
If you sleep with your socks on, the heat will not be released properly, making it difficult for your core body temperature to drop. That’s why it’s no good.
In addition to socks, sleeping with electric blankets or electric foot warmers also interferes with sleep for the same reason. If you use it, warm it up before bedtime and switch it off
when you go to bed. Then, the temperature will naturally drop, so it will not interfere with the drop in core body temperature.
For those who can’t go without socks when sleeping, we recommend leg warmers to warm up your ankles.
Leg warmers are perfect because they keep your feet warm and don’t interfere with the heat release from your feet.

The temperature in the bedroom should be above 18°C

“Are you aware of the temperature in your bedroom?”
In the WHO Housing health guidelines 2018 issued by the WHO in 2018, it strongly recommends that the room temperature inside the home be kept at 18°C (65°F) or higher.
However, most households have not reached 18°C.
It may be surprising, but it seems that western Japan tends to have lower room temperatures. This is because insulated houses are more prevalent in colder regions.
If it’s cold in your bedroom, you’ll need to regulate your body temperature while you sleep, and your body won’t get enough rest.
I think many people take measures against the cold by adding blankets and duvets, but when the duvets get heavy, it can be difficult to change position. Don’t just rely on the bed, be conscious of warming the room.

Bathe to warm your body

It is said to be good to take a bath before bedtime to warm up your body and then get into bed.
When the deep core body temperature rises after soaking in the bathtub, it will try to go down as much as it rises. If you get into bed at sleep time, it will be easier to fall asleep.
It takes more than 90 minutes for the elevated core body temperature to return to normal and drop further. Therefore, it is best to finish bathing 90 minutes before going to bed.
Taking a bath just before bed will leave your core body temperature elevated, making it difficult to fall asleep. If it’s too late to take a bath and you want to go to sleep right after getting out of the bath, it would be better to opt for a shower.
Also, even though it’s important to warm up your body by bathing, a bath that’s too hot is not beneficial. When the temperature is high, the sympathetic nerves are stimulated and you cannot relax. Relaxing before going to bed is also important. It’s best to get in the tub with lukewarm water of about 38 to 40 degrees Celsius.

◎ Reference
Osami Kajimoto “Book of sleep that turns into a refreshing morning for those who can’t get
rid of fatigue even after sleeping enough” (PHP Research Institute)
Seiji Nishino (Director) “Illustrated story of sleep it’s so interesting that you can’t sleep”
(Nippon Bungeisha)
Takafumi Kudo “Tireless Encyclopedia” (Crocodile Books)

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