Did you know that everyone has a unique chronotype? It's the natural inclination of your body to sleep at a certain time, which is commonly known as being a morning person or a night owl.
Knowing and understanding your chronotype can be beneficial for managing your daily schedule, optimizing productivity, and improving overall well-being. For instance, aligning your activities with your natural peak periods of alertness can lead to better performance and reduced sleep-related issues.
Let’s say you are a lion chronotype, for example. You may find that you are most alert and productive in the morning. However, if you are a wolf chronotype, you may be more productive in the evening. Understanding your chronotype can also assist in optimizing your eating habits and mental health. You can enhance your overall well-being by aligning your activities with your natural energy patterns.
But you might be asking: where do these tendencies come from, biologically speaking? How much control do we have over them? And what is my chronotype?
Let’s jump in!
What is a chronotype?
A chronotype refers to an individual's natural tendency towards specific sleep-wake patterns over 24 hours. It represents a person's internal biological clock and determines whether they are naturally more inclined to be a morning person (early chronotype) or an evening person (late chronotype).
We all know morning larks, people whose minds are whip-sharp early in the day, and night owls, who shine their brightest in the evening. Most of us fall somewhere in between, and you probably know which category you naturally lean toward
In sleep science, chronotype refers to a person’s preferred wake-up time and bedtime. It’s their biological disposition toward the timing of activity and sleep. Although all humans are diurnal, clearly there’s a lot of variance.
What factors determine your chronotype?
Whether you’re a morning lark or a night owl is generally less about personal preference and more about your genetics and your stage of life. This genetic predisposition is called your chronotype, and it comes from the Greek khronos, meaning time. Your chronotype is determined by clock gene variants, including a gene called Per3.
Psychologist Azure Grant, Ph.D., states, “Our chronotype is determined by the phase of our circadian rhythm [our biological clock] and our sensitivity to external cues. It impacts our levels of alertness and motivation throughout the day, including peak athletic performance, hunger, and satiety. It affects stress, even blood pressure.”
Most of the systems and processes in our bodies run on internal clocks that generate circadian rhythms, cycles that repeat each day. One of the most familiar ways we experience circadian rhythms is through their impact on our sleep-wake cycle. “These biological clocks are made of tiny molecular machines that respond to a combination of external cues, like sunlight, temperature, or food, but they will also keep running in the absence of those cues,” says Dr. Grant.
“Some people’s clocks run a little faster/shorter than 24 hours, meaning in the absence of external cues they wake a little earlier and get tired a little earlier each day. Those are your larks, your morning people.
“Night Owls, on the other hand, have clocks that run a little slower/longer than 24 hours, meaning they wake up a little later and get tired a little later each day.” Researchers suspect that owls might also be more sensitive to external cues, such as light at night.
“If we were all kept in the dark, without any social cues or societal structures — ‘timekeepers’ like the start of a work or school day, lunch or dinner time — we might all end up running on our own preferred timetables that were wildly different from one another!" Dr. Grant says. "It’s those external cues that keep us all on roughly the same schedule.”
Circadian rhythm vs. chronotype
Circadian rhythms and chronotypes both play a unique part in your sleep-wake patterns, but there’s a subtle difference.
Circadian rhythms refer to your internal clocks that control your sleep-wake cycle. Chronotypes, conversely, can be thought of as how circadian rhythms play out in your everyday life. "Think of your chronotype as an aspect of your disposition,” says Dr. Grant.
"For instance, if you’re an introvert, you can choose to live a more extroverted lifestyle, but because it’s not your natural inclination, you'll likely find yourself coming back to your natural preference again and again — and being healthier and happier when you do."
When you know your chronotype, you can turn it into a productivity tool to help you figure out the best times of day to take on specific tasks.
What are the four chronotypes?
There are several models and classifications of chronotypes, but one of the most well-known is the classification proposed by Dr. Michael Breus, a sleep specialist. In his book "The Power of When," he identifies four main chronotypes based on people's natural inclinations towards specific sleep-wake patterns. These four chronotypes are:
- Dolphin
- Lion
- Bear
- Wolf
1. Dolphin (insomniac)
Dolphins tend to be light sleepers and often struggle with maintaining consistent sleep patterns.
They are more alert in the morning and have energy spurts throughout the day.
Their sleep can be easily disrupted by noise or other disturbances.
2. Lion (early riser)
Lions are early risers and tend to feel most alert and productive in the morning.
They prefer to go to bed early in the evening and wake up early without much difficulty.
Their peak productivity hours are in the morning.
3. Bear (normal)
Bears represent the largest portion of the population and follow a more typical sleep-wake pattern.
They have a relatively balanced schedule, feeling alert in the morning and tired in the evening.
Bears usually follow the typical 9-to-5 work schedule.
4. Wolf (night owl)
Wolves are night owls and have difficulty waking up early in the morning.
They tend to feel more energetic and alert during the evening and nighttime.
Wolves may struggle with early morning commitments and find it easier to be productive later in the day.
It's essential to recognize that not everyone will fit perfectly into one of these categories, and some individuals may exhibit characteristics from more than one chronotype. Additionally, as mentioned earlier, chronotypes are not fixed and can be influenced by various factors, so an individual's sleep-wake preferences might change over time. Understanding your chronotype can help you optimize your daily schedule and improve your overall well-being by aligning your activities with your natural energy levels.
What is my chronotype?
When trying to identify your chronotype, note that it changes with age and exposure to timing cues. To determine your chronotype, you can follow these steps:
Reflect on your natural preferences
Pay attention to your daily energy levels, alertness, and sleep patterns over an extended period. Notice when you naturally feel more energetic, productive, and sleepy.
Assess your sleep-wake schedule
Keep a sleep diary for at least a week, recording the times you go to bed, wake up, and any disturbances during the night. You can also supplement this with data from a sleep tracker. This will help you identify any consistent patterns.
Take chronotype quizzes or assessments
There are online quizzes and assessments available that can give you a general idea of your chronotype based on your responses to specific questions about your sleep preferences and habits. While these quizzes are not definitive, they can provide helpful insights.
Observe your weekend behavior
Pay attention to how you behave on weekends or days off when you have more flexibility in your schedule. If you tend to stay up late and sleep in longer on weekends, it may indicate a preference for an evening chronotype.
Consider your productivity peaks
Take note of the times during the day when you feel most productive and focused. This can give you clues about when your natural peak hours are.
Assess your response to time zone changes
If you've traveled across different time zones, think about how well you adapted to the new schedule. Some people adjust more easily to changes in one direction (e.g., eastward or westward).
Seek professional advice
If you find it challenging to determine your chronotype on your own or have concerns about your sleep patterns, consider consulting a sleep specialist or healthcare professional. They can conduct more detailed assessments and provide personalized recommendations.
Questions to ask to determine your chronotype
To determine your chronotype, you can ask yourself the following questions. Be honest with your answers and try to recall your natural preferences and tendencies over an extended period:
Morning preferences:
- Do you find it relatively easy to wake up early in the morning feeling refreshed and alert?
- Do you naturally feel more productive and focused during the early hours of the day?
Evening preferences:
- Do you tend to feel more energetic and alert during the evening and nighttime?
- Is it challenging for you to wake up early in the morning and do you prefer staying up late?
Midday energy:
- Do you experience a noticeable slump or decrease in energy levels during the midday hours (e.g., after lunch)?
- Does your level of alertness vary throughout the day?
Bedtime routine:
- When do you naturally feel tired and ready to go to bed?
- Do you have a consistent bedtime routine, and does it align with a specific time of the night?
Sleep quality:
- Do you usually sleep soundly and wake up feeling refreshed?
- Do you struggle with falling asleep, staying asleep, or waking up frequently during the night?
Productivity peaks:
Weekend habits:
- On weekends or days off when you have more flexibility, do you naturally stay up later and sleep in longer?
Recovery after time zone changes:
- How do you typically adjust to changes in time zones when traveling?
- Do you find it easier to adapt to new time zones in one direction (e.g., eastward or westward)?
By reflecting on these questions and paying attention to your natural inclinations and energy levels throughout the day, you can gain insights into your chronotype.
Can I change my chronotype?
The short answer: not really. However, most people's chronotype does shift earlier as they get older.
Teens tend to be night owls, with circadian clocks that are delayed by several hours compared with children and adults. Most people gradually advance their circadian clocks to their adult state by age 25. After that, studies show that chronotype is fairly stable across adulthood (one study found that it advanced 10 minutes earlier over a period of 7 years). Many people find that they become more of a morning person as they get older. But it’s not a process you can forcibly accelerate.
Each chronotype has its benefits and drawbacks, but according to Dr. Grant, night owls seem to have some extra challenges. For example, adolescents with late chronotypes are at greater risk for mood disorders, risky behaviors, missing class, and lower grades, and these tendencies may persist into adulthood, with grown-up night owls at greater risk for social jetlag (the discrepancy in sleep patterns between weekdays and weekends), burnout, and depression.
It's thought that social factors and early school and work start times likely contribute to these effects.
"It’s unclear if the culprit is a mismatch between true chronotype and an individual’s choice about when to sleep or something inherent about being a night owl," Dr. Grant says. "Does being a night owl predispose you to health issues, or is it simply hard to be a night owl in a morning world?" That's still a mystery.
The working world is certainly geared toward morning people. "Would night owls have fewer health issues if they weren’t subject to chronic circadian disruption? Does the extra sensitivity that night owls appear to exhibit to external cues like light and food underlie much of the night-owl phenotype, and is that sensitivity to disruption what ends up hurting owls?" We still have much to learn.
Working with your chronotype
Understanding your chronotype can help you work with your own sleep-wake pattern and figure out things like when you’re most focused for work or most creative, the best time to exercise, your patterns of energy slumps,and even your best meal times.
No matter your chronotype, getting morning light, keeping stable meal and activity times, and meaningful social interaction can help you stay healthier, says Dr. Grant. And it’s not just what you do — it’s also what you don’t do. Late meals close to bedtime and bright light late at night contribute to metabolic dysfunction whether you're a lark or an owl.
"Strategies like red-shift for screens, intermittent fasting, early dinners, and reducing carb intake in the evening can help reduce the risk of temporal disruption,” Dr. Grant says.
You can choose to live on a schedule that's different from your true chronotype, but the bigger the difference between the two, "the more you'll negatively impact every aspect of your health,” says Dr. Grant.
Bottom line: It’s better to work with your body’s natural rhythms than to fight them.
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