Ask anyone, and they’ve probably complained about poor sleep, trying everything from meditation to medication, to sleep trackers. Although most adults need seven to nine hours of sleep per night (1), more than a third of all adults in the United States (2) report sleeping less than the minimum, and almost half of adults say they feel sleepy during the day (2).
We can relate.
On top of not getting enough sleep, the sleep we are getting often isn’t as restful as we need. One in five Canadian adults don’t find their sleep refreshing (3), contributing to one in three adults having difficulty staying awake during daytime hours.
There’s no denying it: sleep is important. It comprises about a quarter of our entire lifespan, and more than just being responsible for sweet (and often weird) dreams, we need restful sleep to heal our brains and bodies.
So, what can we do about poor sleep?
Using sleep trackers to monitor your sleep
Enter: sleep trackers!
It makes sense: before we can look to fix our sleep problems, we need to know when we’re having them, and why. This is where sleep trackers have been a great innovation from the last decade. From FitBits to sleep tracking pads under your sheets to full sleep studies capturing your every sleeping moment, learning more about our sleep habits is the first step to improving them.
What is a sleep tracker, and how do sleep trackers work?
A sleep tracker is often a wearable piece of technology, like a sleep tracker watch, ring, or sleep tracking headset. It captures information about your environment and body while you sleep, and in some cases, provides an analysis of your rest.
Sleep trackers commonly look at five physiological categories (4):
- Heart rate
- Body temperature
- Body movements
- Blood pressure
Using different combinations of these biosignals, they’re able to determine when you fall asleep, and when your body cycles through the various sleep cycles. Think about it: when you’re asleep, your body is typically cooler, your breathing more even, and your movements stilled. Advanced sleep trackers can even tell the difference between moving in your sleep, and moving because you’re restless.
More advanced sleep trackers have now started monitoring your brain activity using electroencephalography, or EEG. Tracking brain waves used to be reserved strictly for sleep labs and clinics because the technology was expensive and bulky. Thanks to technological advances, wearable sleep trackers like Muse S are now available for home use, giving you deeper insights into your sleep patterns.
What do sleep trackers monitor?
Let’s look at sleep trackers in more detail. The most detailed sleep trackers available outside of a medical sleep analysis may look at the following details:
Sleep efficiency tracks how long you’re spending in each sleep stage, and the total number of times you’re awakened in the night (even if you don’t notice or remember). Your result will be influenced by the time you’re spending in bed awake vs. sleeping, your total sleep time, and the time spent in deep sleep and REM stages. This usually takes into account your age and gender.
This looks at how quickly you fall asleep, and if your sleep is deep and restful, or light and fitful. There are four sleep cycles:
- Stage 1 (Non-REM): A light stage of sleep where you can still be easily woken up. Your muscles start to relax, and heart rate, breathing, and eye movements start to slow down (5). This stage lasts just a few minutes.
- Stage 2 (Non-REM): Your muscles continue to relax, body temperature drops, and your eye movements stop (6). Your brain activity slows down, but experiences short bursts of activity that last for just a couple of seconds, and likely play a role in organizing memories. Most of your sleep is spent in stage 2.
- Stage 3 (Non-REM): Deep sleep. This is where a lot of tissue repair, growth hormone production, and immune system optimization occurs (5). In order to feel well-rested, your mind and body require high-quality stage 3 sleep.
- REM: The star of modern-day sleep vocabulary! This is where most dreaming occurs and is usually the phase where we remember our dreams most vividly (7). REM sleep first occurs about 90 minutes after you drop off.
It plays a role in your sleep efficiency and is tracked throughout the night so you can see patterns (if you’re always waking up at 5:14 a.m., there could be a reason, like a neighbor’s too-loud alarm, or garbage trucks).
This level of detail isn’t available with all sleep trackers but can come with advanced ones. You can see the position you were sleeping in, as well as how long you were in each position.
Deep sleep is monitored most accurately through polysomnography (PSG) tests. Many sleep trackers use heart rate and breathing as a surrogate for estimating sleep, but most trackers make a guesstimate as to how much you’re actually sleeping. To get exact data on your deep sleep quantity and intensity, an EEG device is necessary.
What are the benefits of using a sleep tracker?
Sleep trackers aren’t doctors: even with the abundance of information they can gather, they can’t pinpoint that your poor sleep is due to honking cars outside, anxiety from your job, or a partner who has restless leg syndrome. They can, however, be useful in your doctor’s diagnosis, and can help a professional determine not just what your sleep challenges are, but how to solve them. They can also be used to rule out certain issues, like sleep apnea, which can cause fatigue, high blood pressure, and even type 2 diabetes (8).
One huge benefit of sleep trackers and sleep sensors is that they promote awareness of the importance of sleep, and when you’re not getting it. They can be useful in motivating you to improve your sleep habits and provide helpful information to your doctor (9). Sleep trackers provide an affordable way for you to proactively take steps to improve your sleep quality – not bad for a small piece of wearable technology!
How accurate are sleep trackers?
Sleep tracker accuracy can vary depending on the type of technology and the biometric data collected. For instance, a watch that monitors your heart rate isn’t going to be able to provide the same level of detail or accuracy that an EEG sensor on a sleep tracking headset can provide.
The image above shows a comparison of EEG data between the Muse S sleep tracker and a traditional EEG device used in sleep labs.
Can a sleep tracker replace a sleep study?
One downside of sleep trackers is that they can sometimes falsely lure you into thinking you’re getting enough sleep, or spending enough time in REM (rapid eye movement) sleep, the most restful phase (9). Even if your reports are showing you’re getting the minimum number of hours for your age, and enough of it is restful sleep, if you’re still feeling fatigued and unrested, it’s important to talk to your doctor about other possible causes and solutions.
When looking for a sleep tracker, ones that use EEG technology, like Muse S, will provide you with the most accurate sleep data – it’s like having a sleep lab in your own home. With Muse S EEG, you’ll also have access to advanced reporting, like the sleep score feature, which provides insight into your nightly sleep quality.
The Key Takeaway?
Overall, sleep trackers can be a useful and accessible way to gain more insights into your own sleep patterns. They can help narrow in on reasons you may not be getting the restful sleep your mind and body need. For more reading, check out our post on how you can improve your overall sleep hygiene.
By tracking data and providing top-line analysis, sleep tech can be a helpful tool in combination with a medical professional to develop a sleep plan that works for you. If you’re not feeling rested, have difficulty falling asleep, or are waking often throughout the night, test one out to see if it can help you.
- Read the National Sleep Foundation’s sleep time duration recommendations HERE >
- Read the Centers for Disease Control and Prevention data and statistics on short sleep duration among US adults HERE >
- Learn if you’re getting enough sleep on the Canadian government’s website HERE >
- Read about Sleep Monitoring on the US National Library of Medicine National Institutes of Health HERE >
- Read Stanford University: A Brief History of Sleep HERE >
- Discover more about sleep cycles with Understanding Sleep Cycles: What Happens While You Sleep HERE >
- Learn about the Natural Patterns of Sleep from Harvard University HERE >
- Read an article on the Mayo Clinic about Sleep Apnea HERE >
- Learn about how sleep sensing technologies support and undermine sleep health HERE >