Sleep is as important to a human body as food and water. We spend about 1/3 of our lives asleep. Sleep affects every system in the body, including the brain. Your brain uses the time that you are asleep to ‘clean’ up tissues, essentially removing toxins and cellular debris so that your brain can function properly when awake. Researchers still have not uncovered all of the functions of our sleep but have shown that if we do not get enough sleep over time, or too much sleep, we increase our risk for chronic health issues such as diabetes, heart disease, and depression.
Just like with cake, more sleep does not necessarily mean it’s better for us. In fact, many recent sleep studies have shown that the old axiom of 8 hours of sleep being our goal is not accurate. In the largest sleep study conducted, it was found that a range of less than 6.5 hours being short sleep and greater than 7.5 hours being long sleep – people who slept outside of the range of 6.5-7.5 had higher mortality rates. In fact, people who slept, on average, more than 7.5 hours/night had the highest mortality rates, suggesting that people who sleep for long hours are not actually sleeping as effectively. (1)
What are some ways that we can optimize reaching the deepest sleep cycles where most of the ‘work’ of our body’s clearing systems is taking place?
Let’s work on the quality of our sleep.
There are things we can do during the day to regulate our circadian rhythms so that our rhythms are better aligned with our sleep needs. Circadian rhythm refers to the natural sleep-wake cycle of our bodies; this cycle is regulated by hormones – both while awake and while asleep. Here are some ways to send messages to your body to regulate your circadian rhythm – starting first thing in the morning:
- First, when you wake up in the morning and reach for your snooze button – don’t hit it! In sleep, we cycle between REM and non-REM sleep – the end of each sleep cycle is REM sleep and this is when testosterone and cortisol levels rise, which prepares us for waking. If you hit the snooze button, you fall back into non-REM sleep, your testosterone and cortisol levels drop, and you wake feeling more groggy and less alert.
If you want to take this hack one step farther, consider a device that wakes you at the optimum point of your sleep cycle such as wakemate . Wakemate is a wristband that tracks your movements and breathing patterns during sleep and will wake you with your favorite music at the optimal point of your sleep cycle, nearest to your set wake up time.
You can take this sleep-tracking one step further with a system like Withings or Oura . These devices track much of your health data and help you to track your entire day. You can use this information to reach your highest potential in all of your daily activities, including sleep. Regulate your circadian rhythm all day long with the information you obtain from your health tracker device and build a personalized sleep routine.
- Learn your sleep chronotype – This goes along with the sleep-tracking device. Sleep expert, Dr. Michal Breus has identified 4 sleep chronotypes – 4 distinct circadian rhythm patterns. If you identify yours, you can structure your day to fit into your natural circadian rhythms. Learn more about sleep chronotypes here. Are you a bear, a wolf, a lion, or a dolphin? This is super cool and if you want to dive deep into using your identified sleep chronotype to regulate your potential throughout your day, check out his book The Power of When.
Use this information to re-wire your whole day – build your schedule around your natural circadian rhythms and you will be more productive, more energized and will sleep better.
I did the quiz and learned that I am a lion. I have adjusted my daily routine to eat breakfast early, do concentrated brain work in the mornings and to exercise in the late afternoons and I have much more balanced energy throughout my day as well as increased productivity.
- If you don’t want to dive into monitoring your whole day/night, don’t worry, there are little tips that can regulate your circadian rhythm without accessing all of that detailed information. First, reduce your blue light exposure in the evening and maximize it in the morning.
Blue light is the spectrum of light from sunlight that blocks melatonin production in the body. Melatonin is the hormone released in our circadian rhythm to trigger sleep, so when we expose ourselves to blue light late in the day, we disrupt our circadian rhythm.
This goes beyond avoiding screens in the 2 hours before bed, though this is a good start. To really cut back on blue light exposure – avoid screens, get blue light blocking screen protectors, avoid LED lights and fluorescent lights, use a dim red colored night light bulb, and/or wear blue light blocking glasses.
You don’t need your health tracking device to tell you this one – get natural sunlight first thing in the morning. This regulates your pineal gland, which releases melatonin at the appropriate times throughout the day. Going outside, or sitting in a bright window first thing in the morning will set up your brain for alert wakefulness for your day and prime your brain for settling into restful sleep at night.
- Another general way to regulate your circadian rhythm is to plan your exercise routine to best prepare you for sleep. When you exercise, your body releases cortisol (among other hormones and chemicals). Cortisol regulates our stress response and is an important hormone in our bodies – cortisol is not entirely negative. It regulates our sleep and wake cycles and controls how we manage stress. There are ways in which you can regulate your cortisol levels – and when and how intensely you exercise is one of them.
If you exercise moderately sometime between morning and several hours before bedtime, you will trigger an elevation in exercise-related cortisol, which triggers a release of dopamine and other endorphins. The mechanism is not fully scientifically explained yet, but it has been established that moderate aerobic exercise improves our sleep quality and helps us to fall asleep easier.
The key takeaway from this information is that exercise triggers an increase in cortisol – if your cortisol levels are regulated well, cortisol will gradually drop toward bedtime. So, we want to get the stimulation from exercise, but not too close to bedtime. Late night high intensity workouts could stimulate an excess of cortisol and affect your ability to fall asleep and/or sleep deeply.
Plan your workouts for sometime between morning and mid-day in order to optimize your cortisol levels for sleep.
Science has some really cool information out there to help us fall asleep more easily and to sleep more deeply and effectively to maximize our body’s glymphatic, lymphatic, immune, detoxification systems and more. Geeking out with some of the newer monitoring devices can help you to maximize your potential physical and mental energies throughout your day. Paying attention to your light sources and your exercise routine can help you to regulate your hormones that are involved in your sleep-wake cycle. By learning your sleep chronotype, you can structure your whole day to support your sleep. And, since the quality of our sleep affects the health of our whole body, especially our brain, this is a practice well worth investing your time.