From Larks to Owls: How Your Chronotype Shapes Your Sleep Timing Preference

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What is a Sleep Chronotype?

When it comes to sleep, it's a deeply personal experience. While some people wake up refreshed at the crack of dawn, others find their creative juices flowing late into the night. This diversity in our sleep patterns can be attributed to something known as "sleep chronotypes." Some of you might have never hear of this, but you’ve probably heard of morning larks and evening owls – two distinct chronotypes. So what is a sleep chronotype? Well, it’s your body’s natural inclination to feel more awake/sleepy at certain times of the day. Some people feel they have the highest energy levels in the morning, while others are super focused only late in the day – and this, in a significant part, is controlled by your genes. Let’s take a deeper dive and explore the science behind what makes us early birds, night owls, or perhaps even hummingbirds.

The Science of Morning Larks and Night Owls

Let's break down the science of the three primary sleep chronotypes:

• Morning Chronotype (Lark): These individuals naturally wake up early and are most alert during the morning hours. Their bodies are primed for rest in the early evening.
• Evening Chronotype (Owl): Night owls experience their peak alertness in the late afternoon and evening, typically going to bed much later.
• Intermediate Chronotype (Hummingbird): Falling in the middle of larks and owls, hummingbirds find their energy levels more balanced throughout the day.?

According to a large study, 25% of people show an early chronotype, 50% and intermediate, while another 25% show a later chronotype. ?Interestingly, there are gender-based variations in chronotype, with men generally having later chronotypes than women, most markedly during adolescence. What’s more, eveningness is associated with an increased risk for psychopathology, poorer physical health and even mortality. However, more research needs to be done to fully understand the neurobiology of chronotypes and their effect on health.

The Sleep Chronotype Puzzle

Picture this: you have a friend who's a morning person, waking up at 5 AM with a burst of energy, and another friend who's a night owl, thriving at midnight. The reason for this variation in our sleep habits could lie in our sleep chronotype, our internal sleep clock. Scientifically speaking, sleep chronotypes are super connected to our circadian rhythm, which is the internal biological clock regulating our sleep-wake cycles. It's managed by a tiny region in our brain known as the suprachiasmatic nucleus (SCN). This nucleus responds to light and dark cues, helping determine when we feel alert and when we feel drowsy.

But it doesn't stop there – genes also play a pivotal role in shaping our chronotype. Genetic variations can influence whether you're inclined to be a night owl or an early bird. One such gene is known as "Period3" or "Per3" that is involved in the circadian clock. Studies have revealed that certain variations of the Per3 gene can be associated with evening chronotypes, making individuals more inclined to be night owls. This genetic component could explain why chronotypes tend to run in families, with generations passing down their sleep preferences. However, our chronotype isn't a fixed trait; it can evolve over time. Factors like aging and shifts in our daily schedules can influence our sleep patterns. Children tend to have early chronotypes, while both men and women become later throughout adolescence, reaching a peak in “lateness” at around 20 years of age, and become earlier again with increasing age. That's why some individuals may find themselves transitioning from night owls in their youth to early birds in adulthood, and vice versa. So next time you’re late for work or classes in the morning, you can’t entirely blame it on your genes.

Using Chronotype Knowledge for Better Sleep

Understanding your sleep chronotype can significantly impact your daily routine. By aligning your activities with your body's natural alertness patterns, you can enhance your productivity and overall well-being. Various tools, including the Morningness-Eveningness Questionnaire (MEQ), can help you discover your chronotype. This questionnaire is freely available and simple to fill out, so it you’re interested in finding out your chronotype, here’s a link.

?With your chronotype in mind, you can tailor your schedule to maximize your productivity and well-being. Early birds can focus on important tasks in the morning, night owls can excel in the afternoon and evening, and hummingbirds can adapt their schedules throughout the day. This is also important in sports, especially when it comes to personalizing training sessions to get the most benefit for an athlete depending on their chronotype.

Final Words

Sleep chronotypes offer a captivating glimpse into the complexities of our sleep patterns. Recognizing your chronotype and syncing your daily routine with it can lead to improved sleep health and an overall sense of well-being and productiveness. So, let's embrace our unique sleep rhythms and awaken each day refreshed, ready to seize the opportunities that lie ahead.

About the author

Alen Juginovi??is a medical doctor and postdoctoral researcher in the Department of Neurobiology at Harvard Medical School studying the effect of poor sleep quality on health. He is keynote speaker and teacher at Harvard College. He and his team also organize international award-winning projects such as Nobel Laureate conferences, congresses with leaders in medicine, charity concerts and other events. Feel free to contact Alen via LinkedIn for any inquiries.