Why do People Feel Tired after Sleep?

Imagine it is a Friday night. Because you had a number of midterms, you didn’t sleep well and were devastated the whole week.

So you decided to make up for it. You turned off your alarm clock and fell into dreams quickly. When you open your eyes again, it is noon on Saturday.

You want to wake up.  Contrary to your expectations, you feel more tired and fizzled out than yesterday. You have to stay at home and your Saturday is ruined.

An oversleeping meme. From theberry.com

But how could this have happened? Why does having had sufficient sleep constitute to a lack of energy?

There are two reasons that cause an over-tired body after a much-needed sleep. First of all, it turns out that every person body has its own sleep-wake pattern; when somebody breaks this pattern, their body will punish them with fatigue. This pattern is called the “circadian rhythm”. Even though every person has their own circadian rhythm, the circadian rhythm of human beings repeats every 24 hours on average. When we decide to violate our own circadian rhythm, whether we make it earlier or later, our body will initialize a “reset” process trying to fit the new rhythm. This process will make us feel lethargic.

Secondly, sleep itself has a cycle. People have on average five sleep cycles every night and each of them last from 80 minutes to 120 minutes. When we sleep in, we are entering an extra cycle. Nevertheless, we may not finish a whole cycle and we may wake up in the middle of this extra cycle. This gives your body information that you still need sleep and makes you feel tired.

There are a lot of problems caused by oversleeping other than ruining a day. The video below shows some of them.

Beyond the video, an article published in March 2017 suggests that sleeping disorder may result in obesity.

So how to prevent oversleeping from happening?

A recent research has discussed the current state and future perspective of treating sleep-wake disorders. The current treatment involves using chemicals to control the tiredness and using machines to track the sleep status.

However, these methods seem too much for me. From my perspective, other than these artificial ways of treating sleep-wake disorders, there are some small things we can do in our daily life to stop oversleeping. For example, we can have a steady sleeping schedule; setting an alert 8 hours after bedtime to avoid oversleeping will be a good way to achieve it. We can also prevent oversleeping through improve the sleep quality; there are multiple ways to improve our sleep quality, such as avoid engaging in exercises at late night.

Sleeping feels good, but people cannot have too much of a good thing. It is hoped that everyone will have a balanced sleep-work pattern.

— Zhaolin Deng