The Science Behind Sleep Trackers


  The world has gone crazy for fitness and wellness devices. Just about every wrist you see these days carries an activity tracker and smartphones are filled with dozens of health and wellness apps all designed to make your life better. Colleagues of mine who attended the Consumer Electronic Show in Las Vegas in 2016 reported that and health and wellness were well represented.

In fact, according to them, you couldn’t walk down a single aisle without coming across at least one booth aimed at improving your physical or mental well-being. If it weren’t for drones and hover boards, then health and wellness would‘ve likely been the hottest industry showcased at CES 2016.

From activity trackers to heart rate monitors, chances are you have some kind of device to help you track your health, including how well you sleep. Speaking of sleep, dozens of studies in the past few years are reporting what many have long suspected: sleep matters…a lot.

So what kind of grade are you getting when you hit the sack at the end of the day? Are you snoozing to the tune of an A-plus or tossing and turning all night for a D-minus? If you have a sleep tracking device, then chances are you can answer that question, with some statistical data to back it up. But do sleep tracking devices really work or could they actually be doing more harm than good?

Why Tracking Your Sleep Matters

If you wonder why tracking your sleep even matters then you should know that study after study has resulted in the conclusion that we are not getting enough sleep, including this one by the Centers for Disease Control and Prevention. We’ve known for years that we should be getting at least seven hours of quality sleep each night. We also know that keeping a consistent time for both going to bed and getting up in the morning is one of the keys to restful sleep. Yet, how many of us stick to that program? In fact, according to a recent study by Sierra Forbush at the University of Arizona, as reported in Newsweek, sleeping in on the weekend – which many of us do – is not good for your heart.

The excuses are endless, which is why so many people are purchasing sleep trackers, which not only help you keep a sleep schedule but they also monitor the quality of your downtime. That’s extremely important because even if you’re in bed for seven to eight hours a night, if you’re not sleeping well, then it doesn’t do you much good. By tracking your sleep you can measure how useful your rest really is, which can help you make changes in order to improve your sleep.

The Science Behind Sleep Trackers

So how do sleep trackers work? If you’ve never used one, you might wonder just exactly how these gadgets track your sleep. The purpose of sleep trackers is threefold: measure your sleep quality, track when your good rest goes bad and help you wake up at the perfect moment. Obviously, no one likes to be hooked up to monitors and cables while they sleep, so sleep trackers provide a great alternative. These gadgets are designed to measure how much time we spend each night in the five different stages of sleep, which are:

  • Stage 1 – this is the beginning of the sleep process when you have just started to doze off. You are still in a very light sleep and can be easily awakened. Often times your muscles begin to contract and slow down.
  • Stage 2 – in this stage your eyes stop moving and your brain settles down and relaxes, which means the body falls into deeper relaxation, as well.
  • Stage 3 – when you hit stage three your brain waves really begin to slow and your body typically doesn’t move at all. This stage is the beginning of deep sleep.
  • Stage 4 – when you hit stage four you are in a deep sleep and in most cases it is much harder to wake a person up in stage four. Your eyes and muscles are not moving and the brain is producing slow moving delta waves almost exclusively.
  • Stage 5 – the last stage is the REM stage, or rapid eye movement stage. Typically, this is when most dreams take place. While your eyes are moving rapidly, your limbs are essentially paralyzed for short amounts of time. The brain waves increase close to the same level as waking hours and your body also sees an increase in blood pressure and heart rate. This is definitely the most active stage of sleep.

The overall purpose of sleep trackers is to measure how much time you are spending each night getting quality sleep, so you can make adjustments to improve your sleep if needed.

Most Popular Sleep Trackers

If you’re in the market for a sleep tracker there are plenty of options. In fact, it might be a little overwhelming trying to decipher which one is right for you. With that in mind, let’s look at some of the most popular choices available, in an effort to help you decide – in no particular order.

  • Withings Aura Smart System $299.95 – at right around $300 this is one of the most expensive sleep monitors on the market, but if you want a better night’s sleep this system is worth the extra cash. The Withings Aura Smart System consists of three separate components instead of just one, like many other sleep tracking monitors.

The main component is the light and sound machine that sits on your nightstand within close proximity to the second component, an app that you download onto your smartphone. The app records your sleep stats, which are monitored and tracked with the third component, a strap that goes under your mattress while you sleep. But that’s just the start. This tracker helps you fall asleep by playing a lullaby and you can set the music to a timer.

It also features a fading glowing light designed to help produce melatonin. The Aura Smart System even tracks your breathing rate and your rate while you sleep, as well as how long you spend in the different stages of sleep. Plus, when it’s time to get up, this sleep tracker helps wake you up at the optimal moment each morning.

  • Jawbone UP3$110.99 – activity trackers come in all shapes and sizes. A growingly popular feature of many activity trackers is the ability to monitor your sleep, as well. If you’re looking for something with a sleek design that combines several features in one then you can’t go wrong with the Jawbone UP3. Not only does it track your heart health and your overall movement, but it also helps you get a better night’s rest.

With the UP3 you will get a sleep monitor that automatically tracks your deep sleep, as well as your light and REM sleep, all while conveniently wearing it on your wrist. The UP3 then records and analyzes the data on a smartphone app and then offers tips to help improve your sleep habits, patterns and overall rest. While it does not come with a screen display, the Jawbone UP3 does provide you with very accurate and in-depth sleep information.

  • ResMed S+ $149 – another great choice is the ResMed S+, which is a non-contact sleep monitor. In other words, you don’t have to lie on a special pad, or put anything under your mattress. You don’t even have to wear a device on your wrist. This tracker combines a unique monitor that sits by your bedside with a smartphone app and another web-based app.

Together they help you gain a greater understanding of how well you sleep and suggestions on how to improve it. The monitor works by measuring your body movement and breathing as you sleep. It also analyzes the temperature levels in your room, as well as the light and noise levels. For those who are driven by numbers, the ResMed S+ also gives you a daily sleep score so you can better understand your sleep habits and try to improve them.

  • Beddit Smart 3 $149.99 – one of the greatest causes of lack of sleep is simply overthinking it. How many of us lose sleep simply because the more we want to fall asleep the harder it gets? With it’s simple design and function the Beddit Smart 3 aims at shifting our focus elsewhere. This smart tracker is placed under your sheets and as soon as you lay on it, it begins to work.

Once you fall asleep, the sensor uses Bluetooth Low Energy to start tracking and collecting your sleep data on the smartphone app located nearby. As long as your phone is within range the sensor and the app will communicate and track your sleep. Furthermore, this device keeps track of when you wake up throughout the night, your light and deep sleep intervals and even the total amount of time you slept. It’s a smart way to monitor your snooze time.

picture of the Sleepace Nox sleep light
picture of the Sleepace Nox sleep light
  • Sleepace Nox $149.99 – another popular sleep tracker that aims at helping you with all things sleep is the Sleepace Nox. This tracker not only monitors your sleep, but much like the Aura Smart, the Nox wants to help you fall asleep and wake you up at just the right time. Offering soothing light and sound, the Sleepace Nox helps you to gently drift off to sleep.

After you fall asleep the app on your smartphone will tell the Nox to go to sleep as well. But the Nox doesn’t stop there. This sleep tracker includes a smart alarm that helps you wake up naturally each morning because it recognizes when you are in light sleep, as opposed to deep sleep. The app will let the Nox know when it should wake you up, within 30 minutes of your planned time.

  • Misfit Shine 2 $99 – this little sleep tracker offers a lot of versatility, which is great if you want an unconventional way to use a sleep monitor. The Misfit Shine 2 and its predecessor, the Misfit Shine, can be worn on your wrist and as a necklace, or you can simply clip it to your clothing. In fact, the company also offers socks and shirts with small pockets if you want to hold the tracker there while you sleep.

As for function, don’t let its small size and lack of display fool you. The Misfit Shine 2 keeps track of your light, deep and REM sleep, as well as when you wake up and your total rest time. Plus, just like Santa Clause, it also knows exactly when you fall asleep and it starts tracking as soon as you do. You can track all the data via the smartphone app, which is both iOS and Android compatible.

  • Fitbit Charge 2 $149.99 – one of the biggest names in activity trackers is also putting a heavy focus on sleep tracking. Enter the Fitbit Charge 2, which looks great and offers great functionality. Just leave it on your wrist when you go to bed and it will do the rest. Unlike many of the aforementioned monitors, this sleep tracker does not analyze your external environment, but it does keep track and learn your behaviors over time.

As the Charge 2 tracks your sleep habits it begins to learn more about you, which helps it offer even more detailed and personalized feedback and suggestions to help improve your sleep. Fitbit Charge 2 tracks your sleep stages and cycles by using the built-in heart rate monitor and it gives you daily updates on your sleep activity.

  • Sense with Voice $149 – last, but not least, is the Sense with Voice. This sleep tracker actually straps onto your pillow in order to detect how much movement you make throughout the night. While the Pill unit senses your movement the other component sits nearby on your nightstand and processes the data it receives from the Pill unit.

The Sense then analyzes this data, together with environmental factors such as noise and light, volatile organic compounds, carbon dioxide light temperature and barometric pressure. It then comes up with a profile of your nightly sleep routine, as well as the factors that could be hurting it. Plus, as the name suggests, you can use your voice to ask for sleep reports, set alarms and other commands. [UPDATE:Hello, the makers of the bedside sleep tracker Sense, is shuttingdown]

The Benefits of Sleep Trackers

So if you and your bed aren’t exactly getting along and you wake up every day feeling lousy, there could be several causes. However, the bottom line is, if you aren’t getting quality sleep then you aren’t going to wake up refreshed. Additionally, your long-term health is going to suffer. Tracking your sleep could be one way to help you improve your sleeping grade.

The main benefit to using a sleep tracker is to give you insight into how effective your rest is each night. Other benefits include being able to connect the dots between a good night’s sleep with a general overall feeling of well-being, discovering habits and patterns that lead to poor rest or discovering a sleep disorder. If the data shows that you’re restless and disturbed throughout the night then obviously you need to change something, or perhaps several things.

The Downside To Sleep Trackers

On the surface sleep tracking sounds like a good idea, but not everyone is convinced sleep trackers work. Additionally, sleep trackers might not be for everyone, and for those who do use sleep tracking devices, it’s important to use them correctly.

Recent studies, including on by Rush University, have shown that these devices might actually do more harm than good. It’s not that sleep trackers are inherently bad, but rather they can have a negative affect on those who use them.

According to the study’s lead author, Dr. Kelly Glazor Baron, “too many people become fixated on the hours of good sleep they get according to the tracker, which causes a lot of stress and, in some cases, leads to insomnia.” Thus, because some users put too much credence into their sleep tracking devices, and in turn too much pressure on themselves to get their desired amount of quality sleep, the same users feel like failures when they don’t achieve their goals. Each passing night becomes more frustrating until they eventually get little or no quality sleep at all.

Can The Problems Be Solved?

So is your sleep tracking device controlling your life? Are you nervous every time you go to bed? Are you worried your device will give you disappointing looks each morning because you failed to sleep well the night before? Relax! You don’t have to live up to your sleep tracker’s lofty expectations. In other words, don’t get caught up in the data. It may take some work, but you have to retrain yourself so that you don’t rely too much on what the sleep tracker is telling you.

Get Your ZZZs

You can use sleep tracking devices as part of a good night’s rest, but it should not be the only factor in how you evaluate your sleep health. Record the data but give it its proper consideration and weight. In other words, don’t make it the “be all end all” of your sleep monitoring process. Focus on a variety of factors and then make the necessary changes and adjustments. So, if you do have a sleep tracker don’t go smashing it with a hammer. It does still have some value. Go ahead and use it, but just don’t let it control your life. Use it appropriately and your sleep grade is sure to improve in no time. Good ZZZZs await you.