Reference; http://seino-1987.jp/html/
Modified and translated by CFJA
4. sleeping arrangements
There are various ways to dress for sleep. Lying down to sleep means that the body’s ability to maintain its own temperature is reduced. Therefore, keeping warm must be a primary consideration. Sleeping naked, overdressed or over-covered with a duvet is not appropriate to maintaining your body temperature. As living conditions vary, it is important to find the right temperature for yourself. Temperatures change during the night and the temperature gradually drops, the coldest time is between 3:00 and 5:00 am at dawn. If you sleep with the windows open or naked, this is the time when you wake up feeling cold and have to wake to adjust your duvet. People live in a variety of climates and in a variety of lifestyles, so it is almost impossible for us to suggest an ideal way to sleep, but it is clear that we must ensure that we do not lose more body heat than necessary.
Modern civilization has developed many heating and cooling systems. Heating systems range from fireplaces, oil heaters, electric heaters, hot blankets, etc,. The widespread use of air conditioning is not good for the body except in environments where the temperature is above body temperature. In Toronto’s climate, there is little or no need for it. This is because humans struggle in many ways to maintain a body temperature in the 36°C range and we are mammals that have difficulty adapting to environments that lower their body temperature. In this sense, most cooling systems, especially air-conditioners, are the most unnecessary, because they have a considerably negative effect on the body.
In the next article, we will discuss the relationship between sleep and air-conditioning, and in the following article, we will discuss the relationship between sleep and heating.