Close your book!
Koreans study a lot. To get into a prestigious university or to get a decent job, we study and study. Even some people pay tribute to students who have a nosebleed due to overstudy. Of course studying is desirable. It helps you broaden your knowledge and improve problem solving skills. It also leads you to go to a good university and get a decent job. But most people who study a lot have a tendency to overlook the importance of working out. In addition they are exposed to much stress. In result, those who commit to studying are likely to hurt their back, get obese and have mental illnesses.
First of all, studying for a long time sitting in front of a desk will hurt your back. You bend your back to read and write. When you keep stooping your spine gets put under pressure. If you just keep studying everyday and don't exercise, you will eventually get a lumbar disc disease. I have a friend who studied for three years to become a civil servant. He studied almost everyday and didn't exercise. Finally he passed the exam to be a civil servant. But he has got a lumbar disc disease and he goes to see a doctor these days regularly.
In addition, if you sit all day reading and solving problems, you are likely to become obese. Specifically in Korea, most of the students who study for entering a college or getting a job are sitting in front of desks all day. Of course you are more likely to gain weight if you keep sitting down and don't work out. That's why Korean students in the twelfth grade gain relatively more weight. They go to school around 7:30 in the morning and study until 11 at night. Sometimes you need to stop studying and go to work out in order not to get obese.
Lastly, some students end up having mental disorders because they are in too much pressure of study. They study very hard because they feel pressure. Pressure causes stress hormones to be released that are detrimental to mental health. So some of the students suffer from depression, anxiety disorder and bipolar. I attended a foreign language high school which is prestigious in my hometown. Only top 5 percent of student could get into my high school. The competition was fierce and its students studied really hard. I could see some of them suffering mental disorder and getting medical treatment from psychiatrists.
From the day of our birth, every minute is about learning. We learn from parents, teachers, friends and books. From books we can earn lots of knowledge. But if we lose our health, what good is the knowledge? We study to live a better life. Hurting the back, getting obese and having mental disorder do not mean you are enjoying quality of life. They are actually ruining it. So if you think you are studying too much, reduce the time to study. Set aside some time to exercise. In that way you'll enjoy much healthier life.