Understanding Circadian Rhythm & Benefits of Maintaining It with Sleep Consistency

We explain what circadian rhythm is, how it works, and explore the health benefits of maintaining it with sleep consistency.

Circadian rhythm is your body’s 24-hour internal clock, which regulates your sleep/wake cycle. Below we’ll explain how it works, what can disrupt it, how to maintain it and the benefits of doing so, plus how to figure out exactly what yours is.

What Is Circadian Rhythm?

The word “circadian” is based on the Latin terms for “around” (circa) and “day” (diem), so your “around-the-day” rhythm dictates the cycles your body goes through--most notably when you wake up and fall asleep. Your circadian clock is controlled by a part of your brain called the hypothalamus that responds to light. As it gets dark, your brain tells your body to begin producing melatonin, which makes you feel tired.

How Does Circadian Rhythm Affect Sleep? Early Bird Vs Night Owl

Although sunlight and the light-dark cycle play a significant role in your circadian rhythm, some people have a natural predisposition towards feeling more awake and energized in the morning (referred to as “early birds” or “larks”), while others are more active and alert in the evening (“night owls”). Opinions on this vary and there is a wide range in between, but it’s generally assumed that more people fall closer to the category of “early birds.” It’s also true that with standard school, work and business hours, society functions more to their body clocks' benefit. Additionally, circadian rhythms tend to change and evolve with age. Children, teenagers, adults and seniors all have different times that their bodies want to get up, eat, go to sleep, etc.

Disruptions to The Circadian Rhythm

Shift work with frequently changing hours, jet lag from switching time zones, certain medical conditions, or even simply choosing to stay up late one night are all things that can throw off your sleep patterns and circadian rhythm. In the long run, studies show this can negatively impact your health in a variety of ways. Many of us often look to catch up on lost sleep on the weekends, unfortunately averaging 8 hours of sleep per night is not the same thing as getting 8 hours of sleep every night. In fact, “sleeping in” one or two days a week can actually disrupt your biological clock by creating an irregular sleep-wake rhythm.

How to Find your Circadian Rhythm

How do I fix my circadian rhythm? Resetting circadian rhythm, or in truth finding out what your natural circadian cycle really is, is easy if you have the time. Simply go to bed when you feel tired, and don’t use an alarm to get up in the morning. Do this for several days, and eventually you’ll discover exactly when your body wants to be asleep. Learn More: How to Reset Your Circadian Rhythm

Maintain a Healthy Circadian Rhythm with Sleep Consistency

Exposing yourself to natural light in the morning and avoiding screens and other sources of artificial light in the evening prior to bed will help align your sleep cycles and reinforce your circadian rhythm (regular light and dark times are a key factor as well). The most important thing you can do to maintain it is focus on your sleep consistency--going to bed and waking up as close to the same time each day as possible.

Sticking to consistent bed and wake times, tracked in the WHOOP app, helps maintain your circadian rhythm.

Your sleep quality will improve and your body will perform better when it can anticipate the onset of sleep every night. Much more on this below...

How Circadian Rhythm Affects Health: Benefits of Sleep Consistency

A 2017 Harvard study discovered that students with consistent sleep and wake times had higher GPA’s than others, despite not actually getting more sleep. WHOOP used this as motivation to begin tracking sleep consistency, and the results we’ve found are staggering. Our data shows that better sleep consistency contributes to:

• More REM sleep, the mentally restorative stage of sleep
• Increased slow wave (deep) sleep, the physically restorative stage
• Lower resting heart rate
• Higher heart rate variability (HRV)
• Improved mental health

We’ve also learned that greater sleep consistency helps you fall asleep faster, and improves your overall sleep efficiency (the percentage of time in bed that you’re actually asleep):

WHOOP data shows that keeping your circadian rhythm aligned with sleep consistency also improves the efficiency of your sleep.

“I started doubling down on sleep consistency and I’ve seen a huge, huge improvement in the time I’m spending in deeper stages of sleep, and I’m actually spending less time in bed.” - Podcast 17: The Circadian Rhythm Sleep Hack

The WHOOP Sleep Planner Incorporates Your Circadian Rhythm

WHOOP is 3rd-party validated to accurately track your sleep in great detail, including a breakdown of the amount of time you spend in each stage of sleep. The app’s Sleep Planner monitors your circadian rhythm and uses it to make nightly recommendations for exactly how much sleep you need, as well as precisely when to go to bed and wake up in order to maximize your sleep consistency and get the highest quality sleep possible.

WHOOP is not a medical device, our products and services are not intended to diagnose illness or any other health problems, and should not be used as a substitute for professional medical advice, diagnosis or treatment.