| People cool off at Gyeongpo Beach in Gangneung, Gangwon Province, July 30, as the heat wave continued late into the night. / Yonhap |
By Bahk Eun-ji
As Typhoon Lekima passed, the nation has endured tropical nights as the heat persists through the nighttime.
The Korean Meteorological Administration defines tropical nights as when the temperature hovers at 25 degrees Celsius or more from 6 p.m. to 9 a.m. the next day. Korea usually experiences this phenomenon in July and August when the rainy season ends.
While the "ideal" conditions for a comfortable night's sleep is around 20 degrees Celsius, the temperatures in most regions across the country exceeds this level. This ongoing heat wave makes it hard for people to get a good night's rest because our bodies can easily lose its natural rhythm.
Doctors say lack of sleep negatively affects health, as it hampers our immune system and makes people more vulnerable to various diseases. It also causes feelings of fatigue during the daytime, which makes it difficult to concentrate and can even contribute to indigestion.
"Try not to force yourself to sleep when you're in bed. Instead, read a book or stretch gently and wait until you feel drowsy," said Prof. Mo Eun-sik, at Korea University Guro Hospital.
Following are some health tips from doctors on how to cope with sleepless hot summer nights.
Check temperature in bedroom
The temperature of your bedroom can have a significant effect on how much and how well you sleep. Especially during the hot summer nights, getting a good night's sleep requires some preparation. The exact temperature can vary from person to person, but doctors and scientists agree that a slightly cool room contributes to good sleep.
In general, the suggested bedroom temperature should be between 18 and 20 degrees Celsius and a humidity level of between 50 and 60 percent for optimal sleep. The body temperature decreases to initiate sleep, so too low temperatures cannot help facilitate this.
"Switch on your air conditioner in your bedroom two to three hours before you go to bed, and use a fan which also produces white noise to block out other disruptive sounds," Mo said.
Other recommendations for keeping bedrooms cool during hot summer nights include keeping heat out during the daytime by closing the blinds.
Take a hot shower
"It probably sounds strange, but taking a shower with icy water before bed will only intensify your insomnia, because the central nervous system of our body will be stimulated," Mo said.
In addition, blood vessels of our skin will temporarily constrict during a cold shower, but the body temperature will eventually rise even higher when the blood vessels expand again.
Take a warm shower or bath, one or two hours before going to bed and stimulating your shoulders and neck with warm water will also help relieve fatigue, Mo said.
Avoid alcohol or caffeine
Drinking a cold beer is tempting when room temperatures are high, but doctors don't recommend if even if the alcohol can be helpful for initially falling asleep.
"It makes you to feel sleepy at first, but it won't last long because it disrupts deep sleep. You will end up waking up more often through the night, as the alcohol stimulates your nerves," Mo said.
Alcohol's diuretic effect will also make people wake up more often. Prof. Kim Ui-joong of Eulji University Medical Center also advised not to eat too much watermelon or beverages before going to bed as well, because it will also cause frequent visits to toilet.
Food containing high-levels of caffeine, such as coffee, tea and chocolate, should be avoided before bedtime.
"Not only how many hours you sleep but also the quality of your sleep matters. You should control your diet as well as how much you eat before sleep," Kim said.
Exercise
Exercising excessively late at night promotes sleeplessness, because the body becomes tense and the sympathetic nerves are stimulated. One should exercise two or three hours before going to bed, and taking a walk or light stretching will be helpful for sound sleep.
"It is also important to maintain your biological clock and exercising at least 30 minutes daily will also help to maintain regular sleeping hours," Kim said.