If You Need an Alarm Clock, You're Doing it Wrong


The average person spends at least one-third of their life sleeping, according to the National Institutes of Health. It’s a vital factor to living a healthy life, and our daily activities depend on the amount of sleep we get each night. But, why? People, especially college students, need sleep, but how much sleep do we actually need? Physiology professor Michael Harris shares his opinion on the issue.

Professor Michael Harris

Professor Michael Harris

Do people really need eight hours of sleep,
or does it depend on the person?

“It differs from person to person [...] I have no idea where that concept came from, but it’s also from different states of development. [For example], babies usually sleep 18 hours of the day, and that’s important for their neural development. Later in life, you need less and less sleep. On the periodic spectrum, babies need lots of sleep, then young children need lots of sleep at different times, and then youth need sleep at different times, and it could go less and less from there.”

How could one find out how much sleep they specifically need?

“It’s going to be trial and error. You would have to make an effort to hold to a regular schedule. Go to bed at the same time for about two weeks and log when you would wake up. Keep a journal. Ask yourself how you feel. The thing that would tell you if it’s working or not is by doing the alarm clock test. If you have a cycle that is regular, you will find yourself waking up and feeling alert in the morning and not having to drag yourself out of bed due to the alarm waking you up. If you have to have an alarm, then you are doing it wrong. If you wake up a minute before your alarm clock goes off, then your circadian rhythm is synchronized.”

When it comes to efficiency in sleeping, are there any real benefits to napping?

“I think so, and there is a lot of literature that suggests that there is. Our brains are so very concerned with stimuli, and we pay so much more attention to a lot more detail, and so our brains get tired. Our modern society provides enough of a metabolic stress that we cannot recover from just one night of sleep. It’s better to recover from that stress with periodic naps.”

How long can a person go without sleep?

“I would say probably a few days, but your body responds very poorly to a lack of sleep, and your immune system doesn’t like it very much. Everything about your constitution and your physiology seems to fall to pieces if you avoid sleep and also if you avoid the right kind of sleep. So, if you can go into slow-wave sleep but are prevented from going into REM sleep, that’s kind of like not sleeping. So, it’s not just sleep, it’s also the kind of sleep you get.”

Do LCD screens (phones, laptops, TVs, etc.) have an impact on our sleep patterns?

“It really does. Zeitgebers, [a German word meaning ‘time-givers’], is an external trigger in which your circadian rhythm will synchronize. Daylight is a profound zeitgeber or synchronizer for our circadian rhythm. We need light to wake up, we need an absence of light to go to sleep. In the absence of light, our body starts producing melatonin, which makes us sleepy, we [then] go to sleep, and then [we] wake up still kind of sleepy. When we get a dose up [of] sunlight, we seem to metabolize melatonin and we seem to be alert.

Screens are a problem in that the light energy they can produce, specifically the blue light, is very much like the spectrum of light that our bodies [have] synchronized to. So, if it’s nighttime, and we check our email, that blue light has an impact on our circadian rhythm because that light is acting as a zeitgeber. Some people are different from other people in which some people are less sensitive to that.” 

What are some things people can do to get the most efficient amount of sleep?

“Having regular schedules is great. Your circadian rhythm is not something that resets every day, it is something that fluctuates on a very slow timescale. So, it is a very bad idea to wake up and go to bed at different times. The idea that people would go to bed at 11 p.m. and then wake up at 6 a.m. during the week and then want to sleep until noon on the weekends and stay up until 4 a.m. will wreck havoc on your circadian rhythm. You can’t do that for two days [and] then think you’re going to waltz right back into things. Your body likes regularity. When it comes to going to bed and waking up at regular times or eating or exercising at regular times, these things contribute to the synchronization to your circadian rhythm. Once your circadian rhythm is synchronized, you’ll find yourself getting the most efficient sleep. There are very learned people in the field that say, ‘If you need an alarm clock to get out of bed, you are doing it wrong.’”