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Chronotypes – What They Are and What You Can Do About Them


Have you ever arrived to work on a Monday morning to see that one energetic coworker with bright eyes and a smile on their face? On the other hand there is that latecomer always looking drowsy with eyes swollen and a cowlick or two. You could say there are an early bird and a night owl in your office. If you are familiar with these words then you already know two chronotypes – two different sleep-wake schedule preferences.

It is well known that some people are light sleepers (with their sleep easily disturbed); some, on the other hand, sleep tight and have no problem with waking up early. So why do some people have sleep disturbances and others don’t? Why do some people have better sleep quality and are able to be active in the early morning whereas others can’t seem to have a good night’s sleep? And is sleep correlated with mental health – your levels of happiness and depression?

Here we talk about different chronotypes, what they are, and how to find and deal with yours. Keep reading to understand yourself and your sleep better.

What Is a Chronotype?

A chronotype refers to a category of various biological clocks. This means each person has their own daily rhythm called the circadian rhythm. Your circadian rhythm is the system which keeps your internal clock going via hormone release manifested in individual preferences when it comes to sleep, like the time when you go to bed and wake up; but also hours in which you are awake and alert. Your circadian rhythm doesn’t only dictate your sleep-wake cycle but also determines the best time for performing activities like eating, exercising, studying, socializing, and resting.

What Are The Different Chronotypes?

Traditionally there has been a division between morning people and evening people, or the larks (early birds) and night owls. According to Doctor Michael Breus, author of The Power of When, there are four chronotypes that he named after four animals – Bears, Lions, Wolves and Dolphins.

This is how he describes each of four chronotypes:

  • Bears are the biggest category – 50% of people have this chronotype. Just like this animal, they have a solar schedule – rise with the sun, enjoy the productivity peak throughout the afternoon and go to bed early. They usually don’t report any sleep disorders but instead have normal, steady sleep.
  • Lions tend to wake up before anyone else and reach their highest energy levels in the morning or mid-afternoon. From there on their activity seems to take a downward trend. Exercising in the afternoon may help boost energy levels.
  • Wolves are most accurately described as night owls. A wolf is definitely not a morning person – this means the Wolf chronotype is set to a late sleep schedule. Being most active at night, Wolves tend to make less healthy choices and are prone to alcohol and drug abuse. However, Wolves are reported to be highly intelligent, creative and productive members of our society.
  • Dolphins are loyal friends and perfectionists who suffer sleep disorders – they struggle to fall asleep and tend to stay awake for the most of the night.

This categorization means there is more to larks and owls – it shows that there are various parts of the day when you might reach your peak performance. Being aware of your biological rhythm allows you to plan your days in accordance with it and improve your productivity and possibly overall life satisfaction.

Discover Your Chronotype          

Now that you know more about sleep patterns you may ask yourself ’What’s my chronotype?’ Luckily, you can take this short sleep chronotype questionnaire by Dr. Breus and learn what your sleep animal is. Once you do so, you can try to tune in to your personal biorhythm.

Ways In Which Your Chronotype Affects Your Life

It has been found that the difference between late and early risers is about 2-3 hours. However, when a person’s internal clock ticks too much out-of-tune with the clocks of others, it will possibly begin to negatively interfere with their daily life – at this stage the person might have a sleep disorder.

For example, most Wolf types don’t have sleep problems, although they may have trouble adjusting to the work schedules of others. Not being able to balance one’s circadian rhythm with that of others is known as social jet lag.

It’s not only about the time and hours of sleep, it’s when all the other activities should be done throughout the day. Dr. Breus points out that our bodies distribute hormones within a period of two hours.  Knowing our chronotype (and hormonal distribution) helps us determine what to do at what time. Some people are known to be always late and grumpy throughout the day, others may be lively in the mornings, but  sleepy during the evening movies – this may affect our social and family life as well as efficiency at work.

Chronotype may affect an athlete’s performance – more interestingly, a study has shown that people prefer sports which go well with their chronotype. Another study has found that there is a link between chronotypes and school performance.

It seems that we pick our life partner based on our chronotype, as well. This is because morning people are not likely to get along with evening types, as they have different sleep patterns.

Evening types and psychiatric disorders

A study by Liia Kivelä (2018) has shown there is a strong correlation between late sleepers of all ages and depression. The author states that evening people have “a lower behavioral activation system (BAS), which in turn leads to lower reward responsiveness and lower positive affect, and consequently depressive symptoms”. Anxiety disorders seem to go hand-in-hand with depressive disorders and eating disorders including bulimia, binge-eating, bipolar disorder and more.

Given that night owls are prone to these disorders special care should be paid to sleep hygiene, that is, choose the right time to go to bed and make sure your hours of sleep go undisturbed by your surroundings.

Can I change my chronotype?

It seems that many people’s internal diurnal (daily) clocks are somewhat flexible, however, there has been plenty of evidence that we inherit them from our parents; scientists have found certain genes which influence our circadian rhythms. To be precise, the length of PER3 gene decides your chronotype. So the answer is to the question is no, but having in mind that your chronotype is most likely flexible, there is no need to worry because there are still some things you can do to better adjust with society.

Your chronotype may change as the body changes, that is, as you grow older. Adolescents are the most sleep deprived social group since their internal clock shifts to a late schedule during the time of their lives when early school hours just can’t seem to match up. As people grow older many switch to an earlier rhythm.

Embracing your chronotype

Whether you are happy with your chronotype or not, it is good to know what your daily schedule should look like. Many athletes and other famous people have based their careers on their sleep schedule, so take a look at this schedule by Fast Company, based on Dr. Breus’ four chronotypes. Dr. Breus also advises taking some melatonin before bed to make you sleepier, in case you are having trouble with going to bed early.

Forcing an unnatural schedule, behavior, or daily pace to your biological inner clock has been proven bad for your physical and psychological health. Make sure to have proper sleep and plan your day according to what suits you best.

Additional Resources

  1. Reiter R.J. Experientia (1993) 49: 654. doi: 10.1007/BF01923947
  2. Doctor Oz. An Interview with Doctor Michael Breus. https://www.doctoroz.com/quiz/quiz-what-your-chronotype Accessed November 23, 2018
  3. Breus M. The Power of When: Discover Your Chronotype–and the Best Time to Eat Lunch, Ask for a Raise, Have Sex, Write a Novel, Take Your Meds, and More. September 13th 2016. Little, Brown and Company
  4. The Power of When, online chronotype questionnaire https://thepowerofwhenquiz.com/ Accessed November 23, 2018
  5. Lack L, Bailey M, Lovato N, Wright H. Chronotype differences in circadian rhythms of temperature, melatonin, and sleepiness as measured in a modified constant routine protocol. doi: 10.2147/NSS.S6234
  6. Goodman B. Do You Have ‘Social Jet Lag’? WebMD. https://www.webmd.com/sleep-disorders/news/20120510/do-you-have-social-jet-lag#1 Accessed November 23, 2018
  7. Taylor M. How to Find Your Chronotype–and Get the Best Sleep of Your Life. Early Bird by Amerisleep. https://www.amerisleep.com/blog/what-is-your-chronotype/ Accessed November 23, 2018
  8. Lastella M, Roach G.D, Halson S.L, Sargent C. The Chronotype of Elite Athletes. Journal of Human Kinetics. Volume 54: Issue 1. December 15, 2016. pp 219–225. doi: 10.1515/hukin-2016-0049
  9. Zerbini G, Merrow M. Time to learn: How chronotype impacts education. PsyCh Journal. October 10, 2017, doi: 10.1002/pchj.178
  10. Lee R. What’s your chronotype? How to find the perfect time to do everything. Accessed November 24, 2018 https://www.cbsnews.com/news/chronotype-michael-breus-perfect-time-to-do-anything/
  11. Kivelä L, Papadopoulos M.R, Antypa N, Chronotype and Psychiatric Disorders. Current Sleep Medicine Reports. June 2018, Volume 4, Issue 2, pp 94–103 doi:  10.1007/s40675-018-0113-8
  12. Kalmbach D.A, Schneider L.D, et al. Genetic Basis of Chronotype in Humans: Insights From Three Landmark GWAS. Sleep. 2017 Feb 1;40(2) doi: 10.1093/sleep/zsw048
  13.  Taylor M. How to Find Your Chronotype–and Get the Best Sleep of Your Life. Early Bird by Amerisleep. https://www.amerisleep.com/blog/becoming-morning-person/ Accessed November 24, 2018
  14. Bellis R. How To Design Your Ideal Workday Based On Your Sleep Habits. https://www.fastcompany.com/40491564/how-to-design-your-ideal-workday-based-on-your-sleep-habits Accessed November 24, 2018

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