A sleep tracker is a smartphone app or device that measures how long and how well you sleep. There are three basic types of sleep trackers:
- Activity trackers that also monitor sleep
- Apps that turn a smartphone into a sleep tracker
- A device that is dedicated solely to tracking sleep.
Basically, sleep trackers are nighttime activity trackers. Regardless of brand, currently most sleep trackers rely on the same basic core technology — an accelerometer, which measures acceleration, the intensity and direction of movement. The exception is the Renew Sleep Clock, which uses low frequency radio waves to track activity. Regardless of how the tracker captures data, the basic measure is still movement. Most trackers make the assumption that the less you move at night, the better the sleep quality.
Similar to activity trackers, most sleep trackers send your sleep data to an app or website that you can access in the morning. The typical “sleep report” will divide sleep into “light sleep” or “deep sleep,” or “less movement” or “more movement.” It will also tell you how long you actually slept (as opposed to simply lying in your bed) and how often you woke up. What it can’t do is break down your sleep into specific sleep cycles, or tell you with precision how much of each type of sleep you get each night. At best, it’s an estimate.
At the moment, no home tracker or app can perform a sleep study that is equivalent to the polysomnogram, which is conducted at a sleep center. The polysomnogram gauges brain activity, eye movement, heart rhythm and muscle movements to determine sleep quality. Nor can an at home sleep tracker diagnose specific sleep problems, like sleep apnea, a condition characterized by the frequent stoppage of breathing during sleep which is accompanied by loud snoring. Of course, if an at home sleep report shows frequent awakenings, a deficiency in deep sleep or other problems, you can share this information with your physician who may then decide to prescribe a polysomnogram.
Although most trackers are similar in function, there are specific differences that may make one type preferable over another. In some cases, the same device that tracks your activity during the day can also function as a sleep tracker by night. However, you have to be willing to wear it to bed, usually around your wrist. If the thought of wearing your tracker to bed bothers you, you may opt for an app that is downloaded onto your smartphone. The catch here is that you have to be willing to sleep with your smartphone in your bed! Finally, there are devices that are neither worn nor placed in your bed, rather they must be placed on a nightstand close to your bed. One sleep tracker due out soon called Beddit, has strips you place on your mattress.
Finally, be sure to select a tracker that provides data in a format that you understand and find easy to use. For example, with some trackers, you can access your sleep information on a website while others require that you use a smartphone. For some people, it may make no difference where you get the information, but others may find reading graphs and data on a small screen to be difficult. Moreover, some trackers provide an overall sleep score, which can be helpful in terms of quickly assessing your sleep quality, while others provide more detailed information. You may prefer one approach to the other.
Want to know more about the different features offered by sleep trackers? Check out Sleep Trackers at a Glance