Have you identified your chronotype yet? It’s an incredibly important piece of information about your individual preferences for sleep, as well as nearly every aspect of health and performance. Knowing your circadian bio type gives you a guide to the best times to do just about everything, from when to go to be and wake up, work out, ask for a raise or interview for a promotion, have a heart-to-heart with your kids or a serious discussion with your partner. And yes, whether you’re a Lion, a Bear, Wolf, or a Dolphin, knowing your chronotype points to the best times for sex and intimacy too!
People see a lot of themselves in their chronotype. That’s because our daily circadian bio rhythms fundamentally influence how we think and feel, our energy and capacity to take on and accomplish all we need and want to do in our days. We live better and more productively when we do so in alignment with our bodies biologically driven preferences. That’s what knowing your chronotype can help you do.
It’s easy to learn your chronotype by taking this quiz: www.chronoquiz.com.
Sometimes people have questions about their results, where what they see in themselves doesn’t line up neatly with what their chronotype says is true for them.
If that applies to you, don’t worry. You’re not alone. Chronobiology is complex and dynamic. So are chronotypes. We don’t all fit perfectly and exactly into neat boxes. Here’s what to know about the subtleties of chronotypes, and how to get the most from them:
Each chronotype comprises a range of attributes, affinities, behaviors and preferences
Within each of the four chronotypes there exists a continuum. Not all Lions wake bright-eyed at 5 a.m., and not all Wolves still have energy to burn at midnight. Some Bears are more relaxed and easygoing than others. And one Dolphin can need measurably more sleep than another. For each of the three main expressions of bio type—sleep/wake preferences, sleep drive, and personality—there are degrees of difference at the individual level.
Hybrid chronotypes exist—especially for BEARS
If your chronotype doesn’t quite align with your personality, habits and lifestyle—or if you see something of yourself in another chronotype as well as your own—you may be a hybrid of a couple different bio types. This can be especially common among Bears. Roughly 50 percent of the adult population are Bears. It’s a large group, with a wide range of preferences, drives, and personality traits.
Bears who fall at the edges of the continuum are quite likely to share characteristics with other chronotypes. There are Early Bears and Late Bears, who share traits with morning-centric Lions and night-centric Wolves. Both Lions and Wolves have lower sleep drives than a typical Bear—so for Early and Late Bears, both groups may need less sleep than their fellow bio types. Early Bears may have a blend of any of the Lion personality traits—their get-up-and-go, ambition, focus, and conscientiousness. The same is true for Late Bears and the traits of Wolves, including creativity, an openness to risk taking, a love of the new and different.
It’s possible for either Early Bears or Late Bears to overlap with the light-sleeping Dolphin bio type. A tendency to sleep restlessly, to experience symptoms of insomnia on a recurring basis is one sign of a possible Bear-Dolphin hybrid bio type. These folks may also share some of the high-strung, brainy personality characteristics that Dolphins have.
Every chronotype can have sleep issues (including insomnia) that affect behavior and performance
Dolphins experience restless, short sleep patterns that overlap with the symptoms of insomnia: trouble falling asleep, difficulty staying asleep, waking very early or waking feeling un-rested and un-refreshed by sleep.
But any chronotype faces the possibility of these sleep issues, and changes to sleep patterns that may make it harder to distinguish their fundamental chronotype. Lions and Bears are good sleepers, broadly speaking, but a Lion who often wakes at 3:30 in the morning, or a Bear who falls asleep early but wakes often throughout the night both face insomnia-like symptoms put them in direct, fatiguing conflict with society’s sleep-wake clock like Dolphins also are. Same is true for the Wolf who can’t fall asleep before 1 or 2 a.m.
And remember, for every chronotype, sleep and performance are influenced by biological and genetic factors as well as circumstantial and environmental ones. A Lion who consumes caffeine after dinner may not fall asleep before 11 p.m., but still wake at 5:30—and feel significantly less Lion-esque in the morning as a result. Bears who are dedicated daily exercisers may find themselves adhering to something closer to a Lion-like bedtime and wake time. Wolves who can make their daily schedules align with their bio type (for example, by starting and ending work later in the day, or not having to regularly get up at dawn to care for a small child), may get all the sleep they need—and may have less of the typical Wolf’s impulsivity and emotional ups and downs as a result.
It’s possible you’re in a transition between chronotypes
Chronotypes are the expression of our individual genetic and biological identity. We sleep, feel, and perform best when we align our daily lives with our chronotype’s preferences and drives. We can’t change our chronotypes. But chronotypes do change at certain points in our lifespan. As children, we’re mostly Lions, and in adolescence, nearly all of us are Wolves. By about age 21, we begin to settle in to the chronotype that will stay with us through decades of adulthood, until about age 65. At that point, sleep patterns and sleep drives may change, with more older adults becoming Lions or Dolphins.
It’s not always easy to identify with your chronotype
Learning about your chronotype can take you quickly to a pretty personal place, and sometimes it gets uncomfortable. We don’t always have a simple time seeing ourselves as we actually are. It’s not uncommon for people, upon learning their chronotype, to wish they were another type. For example, a lot of people want to be Lions. But Lions have struggles and weaknesses alongside their strengths, just as all chronotypes do. There are advantages and disadvantages that come with every bio type. And chronotypes are just that: a biological reality, not a statement about character, or potential.
If you’re not sure about your chronotype, there are several things you can do to clarify your bio type.
Take a look at your parents
Chronotype is part of our genetic identity. We inherit our genes from our parents. Most people have at least one parent who shares their chronotype. If you’re a Wolf who’s not sure about that designation, take a look at Mom and Dad. Did either of your parents start packing school lunches at 11 at night—probably the same parent who had a hard time getting you to school on time before 8 a.m.? Bears, you’re in a broad type, with a lot of internal differences (see above). There’s a good chance, though, that one or both of your parents had the middle-of-the-road sleep patterns—not too early, not too late—that characterize Bears. Lion Moms and Dads are pretty easy to spot. They’re the greet the sunrise types, who have their most abundant energy at the start of the day. Dolphin parents are hard to miss, too. They’re routinely light on sleep, whether from staying up late or getting up early—or both. Their lack of ability to sleep soundly for a full night might be something they talked about regularly. When taking in to account your parents’ sleep-wake habits and preferences, remember that as we age, more people move into Lion and Dolphin chronotypes. For a best comparison, look at your parents in middle age.
Rate your energy level
This is a good exercise for anyone who isn’t convinced their chronotype match-up is right. It’s especially useful for Bears who feel uncertain about that match, and who may be Early Bears or Late Bears. It’s a way to make a basic assessment of your chronotype, without the potentially distracting detail of a full chronotype profile, is to measure your energy level. It’s simple.
Using a scale of 1-5, rate your energy level on a typical morning. Using the same 1-5 scale, rate your energy level on a typical evening. Do your best to be honest and realistic. Don’t use your most exhausted day, and don’t overestimate your energy. Got your two numbers? Now, subtract your evening energy rating from your morning energy rating. Depending on your numbers, you can have a positive or a negative number (or zero, of course). Here’s how energy ratings match up to chronotypes:
Wolf: -4, -3, -2
Bear: -1,0, 1
Lion: 2, 3, 4
Learn about your ‘adjacent’ chronotype
For people who straddle the line between chronotypes—most often, that’s going to be Bears, who are sharing characteristics with Lions or Wolves—it makes sense to deeply familiarize yourself with the profile and timing preferences of that second chronotype. That’s how you’ll customize your approach to living in sync with your individual bio time. Here’s an example. For a Bear who’s really a Late Bear, with evening preferences, going for a run at 7:30 a.m. isn’t optimal—and you’re not likely to stick to that exercise routine. Borrow from the Wolf’s playbook and schedule a run for after work, when your athletic performance rhythm is more likely to be at a peak for the day.
The point of understanding your chronotype is to use that information for its maximum benefit for your health, your performance, your relationships. Embrace your hybrid chronotype, and put the most useful, relevant information to work for you.
Use the 80% test
Because of the degree of individual biological differences that exist within chronotypes, and because of the influence of external factors on how we sleep and feel, it’s not always realistic to expect a perfect match. I encourage my patients to gauge whether the chronotype they’ve assessed to match is an 80% fit. That signals a great majority of patterns, preferences and characteristics are in alignment with your sleep and waking life. As you continue to pay greater attention to your sleep and your daily performance, you may see that percentage climb, as my patients often do.
Another way to feel more confident about the right-fit of your chronotype? Ask people close to you for feedback. Others who know us well can sometimes see us more clearly than we see ourselves, and provide a welcome reality check.
Take your temperature
This takes a little bit of time, but it’s a way to take a simple biological measurement of your chronotype. To do this accurately, you’ll need a digital thermometer, and an evening when you can commit to taking your temperature hourly over a period of several hours. Core body temperature fluctuates throughout the day, driven by circadian rhythms. With the exception of Dolphins, all other chronotypes experience a drop in core body temperature in the evenings. (For Dolphins, core body temperature actually rises at night.) Different bio types experience this drop in body temperature at different times. It’s a small change, often of only a few tenths of a degree (which is why you’ll need the digital thermometer).
Starting at 5 p.m. and continuing hourly until bedtime, take your temperature. The timing of the slight downward shift provides important information about your chronotype.
Lions will see a lower temperature around 7 p.m.
Bears will see their temperature drop around 9 p.m.
Wolves will see their temperature dip around 10 p.m.
To learn all the details on how your bio rhythms affect your sleep, your health, and your performance, check out my book, The Power of When.
Michael J. Breus, PhD
The Sleep Doctor™