A student wakes up at 1:30 PM, 30 minutes before class. He quickly washes his hair and packs his class materials. With his hair still damp, he runs up to his classroom. After all his classes and clubs, at 10 PM, he calls his friends and orders food delivery with a bit of chat. From midnight, he begins to study. His bedtime is unpredictable. Though it is an extreme case, an irregular lifestyle such as this is very usual in POSTECH.

Among both undergrads and grad students, the largest percentage, around 40%, responded that they go to sleep at between two in the morning and three. People with three to four as their bedtime also take a big portion of the population, amounting to 10%. This means that there is 50% chance that a randomly picked Postechian is likely to go through difficulty in morning classes. Even though he or she does not have classes in the morning, the shift in sleeping time might cause some problems.

The lack of sleep may cause serious problems in body-functioning, especially in the brain.

Sleep has a function of coagulating what is learned in consciousness. Though there are newly suggested counterexamples, it does not change the fact that a lack of sleep has some negative influence on memory conduction.

Also, the hypothalamus in our brain is negatively affected without sleep. A sleepless life causes unstable emotions, which then causes a reduction in motivation.

Our body is designed to fit the circadian cycle. The secretion of hormones and regulations partly depend on the cycle; however, the cycle is actually a little faster than the actual 24-hour rotation of the planet. What synchronizes the difference is the sun. The repetition of an irregular life pattern causes worse and worse living conditions.

Not waking up early implies the loss of a chance to eat breakfast. Without enough glucose for fuel, the brain cannot function to its maximum potential. The lack of breakfast might deteriorate learning capability.

There might be extreme cases of people who have just the right brain function levels even with three or four hours of sleep. But what is important is that most of us are not in that case. Experts advise that the most reasonable sleep time is seven to eight hours in a right frame of time to wake up with the sun.

In a school like POSTECH, which requires a huge load of work of each student, sleeping seven to eight hours might sound luxurious. But it actually is not. Managing little pieces of time usefully and prioritizing work rightly will transform the originally given 24 hours of a day to 30.

☞ The article was advised by Prof. Jung Ki Kim.