What sleep environment raises the quality of midsummer sleep?

2023.08.01

Are you having a hard time sleeping in the heat of the day, when the maximum temperature is over 35 (95 F) degrees? Sleep is essential to overcome fatigue. It’s hot and it’s hard to
recover from fatigue if you wake up often in the middle of the night. If you have trouble sleeping at night, you may want to review your sleep environment.

What is the ideal bedroom temperature?

Do you turn on the air conditioner when you sleep? Now that electricity bills are soaring, there are probably many people who say, “I’m worried about the electric bill if I leave it on.”
However, heat interferes with sleep.
The temperature range that doesn’t interfere with the quality of sleep is said to be 25-26 celsius degrees (75-79 F) in summer and 20-22 (68-73 F) degrees in winter, and the ideal humidity is 50-60% all year round.
If the temperature is too high or too low, or if the temperature changes significantly during sleep, the autonomic nervous system will continue to work to regulate body temperature.
Under those conditions, the brain and body won’t rest.

Be aware of cold head and warm feet

Another point is to keep your brain cool and your body warm. In fact, there is a difference between a comfortable temperature for the brain and a comfortable temperature for the body.
The comfortable temperature for the brain is 22-24 (71-75 F) degrees, as heat tends to build up in the brain. However, in the case of Japanese people who have less muscle, the body feels cold at that temperature in the summer. Therefore, cover yourself from the armpits down with a futon (quilt) to keep your body war.

A/C is cheaper at night than during the day

Regarding the above, it is ideal to leave the air conditioner on while you sleep. However, the electric bill is still a cause for concern.
Panasonic was testing the cost of electricity when the air conditioner was left on at night in the summer. Based on data from air conditioners that turn on cooling after 20:00, the average power consumption per hour was 92 W, and it appears to be about 23 yen when used for 8 hours.
By the way, this is based on the Aeolia PX series nighttime cooling log data, and the estimated electric bill unit price is 31 yen/kWh.
“If it’s 23 yen per night, it’s probably cheaper than you think.” According to the company, the greater the temperature difference with the outside air temperature, the more power it consumes.
In addition, when comparing “3-hour off timer operation” and “continuous operation”, it has been reported that “continuous operation” wakes one up less often and for less time during the night.
For those who wake up often in the middle of the night due to heat or difficulty sleeping, please review the temperature and humidity during sleep so that you can wake up refreshed the next morning and start the day comfortably.
◎ Reference
Panasonic “Aeolia” survey “Fact-finding survey on sleep in the summer of 2023”
https://prtimes.jp/main/html/rd/p/000000801.000024101.html

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