Millions of people across the world are now wearing activity trackers on their wrists to keep tabs on everything from their heart rate and oxygen levels to their step count.
Activity monitors can reveal the most significant cause of inactivity, namely, sleep, among their many other uses.
How effective are they, though? What can and can’t sleep tracking devices tell you is discussed below.
Table of Contents
Wearable fitness trackers: what are they?
The label “fitness tracker” refers to a device that can be worn on the wrist or around the waist to monitor the user’s activity and vital signs. There are a variety of cutting-edge fitness trackers on the market now that can sync with your mobile device or computer. The majority of them include three axis accelerometers that enable them to measure just how rapidly a person moves in any direction. Algorithms are then applied to this data to help make sense of the motion.
What’s the deal with these fitness monitors?
These days, most people wear their fitness trackers either on their wrists like a watch or on their waists like a belt. The tracker’s sensors log every piece of data they take in. The fitness tracker sends its collected data to the connected device, usually a smartphone or computer. This occurs whenever the device is synced with a computer or mobile device.
Using sophisticated algorithms, the program organizes the incoming data into meaningful insights for the user. It’s how the person keeps tabs on their daily activity, such as their heart rate, exercise, and even sleep. Based on the existing data history, patterns can be identified. This data is then outputted for the user to review and use to inform their future fitness decisions.
When you go to sleep, how does a fitness tracker know?
The “Sleep Mode” feature is standard on most modern wearable fitness trackers. In order for the device’s data collection to be precise during the user’s sleep hours, the user must switch to this mode. If this isn’t done, measurements will be taken as if the person is awake and active.
Actigraphy is the practice of monitoring sleep quality by the monitoring of movements while asleep by means of an accelerometer. Actigraphy was recognized as a valuable research tool by the American Academy of Sleep Medicine in 1995, although its clinical utility was still debated at the time. Actigraphy is a straightforward method of monitoring a person’s waking and sleeping hours throughout the night, which might be helpful for people with sleep disorders.
What is the objective of actigraphy?
Through the use of a three-axis accelerometer, a wearable fitness tracker can be used for actigraphy, which records the wearer’s every movement, no matter how slight. If the fitness tracker includes a gyroscope, it could provide additional information. Experts define sleep parameters, and then unique algorithms are built to interpret the tracker data in light of the sleep data.
Numerous sleep latency studies are recorded with actigraphy. It is a useful tool for diagnosing sleep disorders, mental illness, and dementia that affect one’s circadian rhythm. When compared to studies done in sleep laboratories, this type of research can yield more accurate results because it is conducted in a more natural setting. Nevertheless, due to its numerous flaws, it is rarely used as the primary method of information gathering in rigorous scientific studies.
How Reliable Are Wearable Fitness Trackers When It Comes to evaluating the quality of Sleep?
Actigraphy is a key component of wearable fitness trackers for assessing sleep quality. However, actigraphy has its limitations as a tool for measuring sleep duration and quality. There is a large error margin in most actigraphy-based wearable fitness trackers. Unless the user manually toggles out of sleep mode after stepping out of bed, the device may mistakenly report that an awake person who is lying in bed is still asleep, or it may fail to register the user’s activity and movement.
The tracker can’t tell the difference between normal sleep and sensitive sleep, either. As a result, the wearer’s fitness tracker can think they’re enjoying a good night’s rest, even while they’re actually wide awake and just sitting there. The user may also make a mistake if he or she forgets to put the tracker into sleep mode.
How can scientists evaluate sleep quality in controlled environments?
Numerous tools exist for diagnosing the causes of sleep disturbances. Clinical interviews, sleep diaries, and polysomnography are all examples. Polysomnography, or PSG, is what sleep researchers prefer to use in the lab to study how people sleep.
During this procedure, electrodes are attached to the scalp in order to record electrical activity generated by the brain. Some skull shaving may be required for good electrode attachment.
They are able to tell the difference between alpha, beta, theta, and delta waves because they are recording the brain waves directly. While this is the most precise method for measuring sleep quality at the present time, it is also the least practical. A polysomnography provides much more reliable data than a portable fitness tracker. However, they may be used on children and newborns because they are considered a less invasive method of monitoring.
Exactly what do these devices keep tabs on while you sleep?
There is a plethora of sleep trackers available, and more are being introduced regularly. Most of these trackers are designed to be worn on the wrist. Some can be placed on a bedside table, while others can be clipped onto a pillow.
These devices have different features, but some of the most common ones are:
a. Time spent sleeping:
The devices are able to record your sleep and wake times by monitoring your periods of inactivity.
b. How well you slept:
The tossing and turning and waking up in the night can be monitored with a tracker.
c. Sleep progresses in stages:
Some monitoring systems analyze your sleep cycles and set your alarm for the lightest stage of sleep. Theoretically, that should help you wake up faster.
d. Environment-related variables:
There are gadgets that keep track of the ambient conditions in your space, such as the amount of light and the temperature.
e. Daily situations:
Some trackers ask you to input details about the day’s events that might have an impact on your sleep, such as the amount of caffeine you consumed, when you ate, or how stressful your day was.
Understanding Your Sleep Habits
Sleep specialists state that while sleep trackers can provide a wealth of data about your sleeping habits, they are not a substitute for a reliable sleep monitor.
Instead, inactivity is monitored as a stand-in for sleep time.
A medical sleep study, in which your brain waves are monitored and analyzed to determine the different stages of sleep you cycle through each night, is the only way to get accurate information on your sleeping habits. Sleep apnea and other sleep problems can be correctly identified with the use of such research.
Despite this, tracking devices can be extremely helpful for illuminating trends in one’s sleeping routine.
- Do you find that you need more sleep if you go to bed at 10 p.m. and wake up at 6 a.m., but that you can get a good night’s rest if you sleep from 11 p.m. to 7 a.m.?
- Do you find that you sleep better on days that you work out or when the temperature in your bedroom is lower? Are you able to get a good night’s rest if you consume some caffeine after lunch?
With the tracker’s easy-to-understand graphs or reports, you’ll have something to think about on a regular basis and be able to notice trends with relative ease.
See a doctor if poor sleep is causing you significant health problems. If you’re otherwise healthy yet curious about your sleep habits, a tracking gadget could be useful.
