Making Sense of Your Sleep Tracker

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With the rising popularity of wearable technology (think smart watches, devices, and apps), there are now countless options to track your activity. For example, with the right applications, you can count the steps you take each day, monitor your heart rate, and more. There are also apps and tools that you can use to monitor your inactivity… that is to say, the time you spend asleep. The idea behind sleep tracking tools is that they help you identify any potential roadblocks to rest, and make the necessary corrections.

If you recently picked up a new sleep tracker and don’t know where to start, we are here to help! There are a number of important metrics that a sleep tracker can help you quantify, such as your sleep stage and heart rate. Let’s take a closer look at how tracing these metrics may empower you to get a more restful night’s sleep.

Sleep Stages

One of the most critical functions of a sleep tracker is to assess your progress through the different sleep stages. This is important because, in some stages, you may be in a deeper sleep than others. You can use a sleep tracker to ensure that your alarm goes off when you’re in the right sleep stage, meaning that you’ll wake up feeling refreshed rather than groggy and disoriented.

What are the sleep stages?

There are basically five sleep stages to be aware of; again, your sleep tracker can help you monitor your activity through each.

Stage 1. During Stage 1, the body prepares for sleep by ceasing muscle movement. The movement of your eyes behind the eyelids starts to slow. This is a very light sleep, and you can probably still be roused by a noise or sudden activity near where you are sleeping.

Stage 2. By the time you reach this second stage, you are fully asleep. You are no longer aware of your surroundings. Your eyes will slow further, or even stop moving completely. Additionally, Stage 2 begins the regulation of your breathing, heart rate, and body temperature.

Stage 3. Once you enter the third stage, your brain waves will start to settle down. Your muscles will relax, and your breathing will decelerate even further. Stage 3 is a deep sleep, and you may find it hard to wake from it. In fact, if your alarm clock goes off when you’re in Stage 3, you’re likely to feel very disoriented or “out of it.”

Stage 4. Your brain waves slow further, and you will find it even harder to wake up. It is often assumed that this is the stage where muscle and tissue repair takes place. The brain releases hormones that guide this process.

Stage 5 With the fifth stage of sleep, you achieve REM, or rapid eye movement. Not only do the eyes begin moving swiftly behind the eyelids, but the breathing becomes shallow and fast. Stage 5 is when you dream, which allows your brain to activate its learning and memory abilities, sorting through information from the previous days, weeks, and months. REM sleep is essential for you to wake up feeling rested, and it usually happens once you’ve been asleep for 90 minutes or so.

Not Getting Enough REM sleep?

One of the most valuable roles your sleep tracker can play is to alert you when you’re not getting sufficient REM sleep.

This is a big deal: Science has determined that insufficient REM sleep may actually shorten your lifespan. Though this phenomenon is still not entirely clear, the current thinking is that REM sleep is required to bolster your immune system; failure to get enough deep sleep leaves you at a higher risk of infection. Additionally, because REM sleep is required for your brain to sort information, a deficit of REM sleep may impair your cognitive ability during the day, potentially resulting in chronic fatigue or grogginess.

If your sleep tracker reveals that you’re not getting enough REM sleep, there are a few practical steps you might consider. Cease drinking alcohol late in the day; while alcohol can make you drowsy, it also impedes the quality of your sleep. Turn off any blue light-emitting electronic devices at least an hour before bed. And, maintain a consistent sleep schedule, going to bed and waking up at about the same time each day.

Heart Rate

In addition to monitoring your sleep stages, a sleep tracker can also help you evaluate your nocturnal heart rate.

Generally speaking, when you have a lower resting heart rate (RHR) at night, it means your body is recovering from the exertion of the day. For the average, fairly healthy person, a nocturnal RHR may be anywhere from 40 to 60 beats per minute (bpm).

If your nighttime RHR is higher than that, it could be a result of drinking caffeine or alcohol too late in the day, or eating junk food (especially foods that are high in sugar or salt). Easing back on the nightcaps and evening snacks may help. An elevated heart rate may also point to stress or anxiety. Consider some soothing activities before bed: Meditation, yoga, journaling, or soaking in a warm bath.

Meanwhile, if your RHR gets down into the 30s, it could potentially point to a more serious underlying condition, including a thyroid problem or inflammation of the heart. In this situation, it’s probably wise to schedule a check-up with your doctor.


Your sleep tracker may also help you monitor any movements your body makes during the night.

It’s not unusual to twitch, roll over, or move around a few times during the night. If your sleep tracker displays continuous motion, and you wake up still feeling fatigued, that could point to a problem.

Sometimes, movement in the night is caused by anxiety. An anxious mind often causes your body to feel more restless, potentially making it harder for you to fall into that REM sleep your brain requires. Again, developing a soothing bedtime routine may help.

Tossing and turning at night could also result from overstimulation, and lead to the possibility of your senses completely shutting off. For example, is there too much blue light in your room? Too many loud or abrupt noises? One way to reduce nighttime movement may be to create a better sleep environment.

Nighttime motion could also suggest an underlying medical condition, such as restless leg syndrome (RLS) or sleep apnea. If you have an overwhelming urge to move your limbs during the night, that may be a sign of RLS. Meanwhile, sleep apnea creates interruptions in your breathing, which can cause you to wake up throughout the night, tossing and turning. These are both concerns that warrant medical attention.

Sleep Interruptions

One final thing you can monitor with your sleep tracker: Sleep interruptions.

There are plenty of reasons why you might find yourself waking up during the night. If you have sleep apnea, you could wake up because you’re having a hard time breathing. Stress, particularly following a major life event, can also cause you to sleep fitfully. Alcohol, unhealthy sleep environments, and arthritis pain may also rouse you from your sleep prematurely.

Once morning comes, you may not remember waking up during the night… which is where your sleep tracker comes in handy. If you’re waking up often, it likely means that your brain isn’t progressing through the sleep stages as it should; specifically, you may not be getting the restorative REM sleep you need. This can lead to daytime fatigue and grogginess.

As for improving your restfulness, there are a number of tips to consider. Spend a few minutes before bed jotting down a list of your worries, or just a to-do list for the following day. This can be a good way to clear your head before bed, reducing the risk that you’ll wake up due to anxiety. A comfortable mattress and a cool, dark room are also essential.

If you believe your interrupted sleep is due to a health concern, such as arthritis, back pain, or sleep apnea, make sure you see a doctor. The right treatment may relieve your symptoms, allowing you to finally get the solid, steady rest you need.

Final Thoughts

Are you having trouble getting good, restorative sleep? A sleep tracker may help you identify the underlying reasons, potentially signaling some helpful lifestyle changes or even the need for more advanced medical care. See if your sleep tracker can guide you toward a better understanding of your own sleep habits.

Gravatar for Andrew Warren

Andrew Warren

Andrew is a Charlotte, NC native who learned the importance of a good night’s sleep in college after too many late nights in the library. Today, he helps connect Mattress Clarity’s array of resources with people looking to get a better night’s sleep. He enjoys researching the links between sleep and health, nutrition, and exercise as well as finding practical ways for people to improve their sleep quality.


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