Not so long ago, the only way to track your sleep patterns was to visit a sleep clinic and spend the night in an unfamiliar bed with assorted wires and probes attached to you. With the recent explosion in health tracking apps and devices, however, there are now hundreds of options available. Not surprisingly, some are better than others, and all at-home sleep trackers have their limitations in comparison to a professional evaluation. Used properly, however, sleep trackers can be a useful tool in providing general information about your sleep habits.

StepsPart 1Part 1 of 2:Choosing and Using a Sleep Tracker

1Download a sleep tracking app for your phone. A simple search of your phone’s app store will reveal dozens of sleep tracker options, some free and some for sale. Nearly all of them, however, rely on your phone’s existing accelerometer, which detects movement.XBasically, you open the app and keep your phone in your pocket when you go to bed. If you are moving little or not at all, the app records this as sleep. Some use algorithms to assign amounts of movement over periods of time as evidence of particular phases of sleep (such as REM sleep). In the morning, they record and report the results, often with a graph and statistics.Some more advanced apps offer additional features, such as flexible alarms that supposedly will wake you up at just the right time in your sleep cycle — that is, not jolting you awake with an alarm right in the middle of one of your REM cycles. The ability of these devices to do so, and the utility of doing so regardless, are debatable, however.X

2Use a fitness tracker or smart watch. Some people have taken to wearing fitness tracking devices — often bands, watches, or clip-on devices — to record their daily physical activity and monitor some of their vital signs. If you keep the device on at night, most all of them can also track your sleep as well.XLike phone apps, most wearable trackers utilize an accelerometer to detect movement. They use this movement data to determine the amount and quality of your sleep.For people that find it uncomfortable to wear a wristband during sleep, there are also versions that utilize a thin band that stretches across the bedspread and underneath you.Visit the websites affiliated with the various brands of popular fitness trackers and/or smart watches (FitBit, Apple Watch, Pebble Smartwatch, Garmin Vivo, etc.) for detailed operation instructions.

3Understand the benefits and limits of accelerometer-based trackers. By utilizing technology that already exists in virtually all smartphones, accelerometer-based sleep trackers provide a simple, easy, cheap way to analyze a night’s sleep. For all its convenience, though, actigraphy (measurement of movement) has its limits in tracking sleep.Remember, on an essential level, that these devices track movement, not sleep. The device can’t actually tell if you are asleep, or how you are sleeping; it makes assumptions based on your movement patterns. If the way in which you sleep does not fit the supposed “standard” profile, the accuracy of the device will suffer accordingly.XIf, for instance, you were to try out multiple sleep trackers at once, the results would almost certainly be different, and perhaps widely disparate.Thus, while devices that rely on actigraphy have their place in tracking sleep, most sleep experts strongly favor polysomnography, which records a range of vital signs and movements (from eyes to feet) at once. Of course, such devices still exist almost exclusively in clinical settings.X

4Watch for new developments in sleep trackers. As interest in consumer fitness tracking technology increases, new sleep tracking options will likely become widely available. Some devices, which can combine wearable monitors with components that sit on your nightstand, already incorporate elements of polysomnography into the home setting.XXFive years ago, few people used or had even heard of sleep tracking devices; five years from now, the range of sleep tracking devices available may be vastly different from today.Part 2Part 2 of 2:Evaluating the Results

1Know the basics of sleep patterns. While everyone experiences sleep differently, in general terms it occurs in repeating stages of lighter and deeper sleep. Experts delineate four stages of sleep, three non-REM (NREM — N1, N2, N3) and REM sleep. The stages usually repeat every 90 minutes or so (with individual variations).XREM sleep (referring to “rapid eye movement”) is the deepest stage of the sleep cycle, and often considered the most essential. In reality, however, making it through the entire cycle multiple times (ideally 4-5 times for most people) is important for adequate rest and good health.The standard recommendation that adults should strive for 7-9 uninterrupted hours of sleep per night is based upon this need to complete several full sleep cycles.

2Use sleep trackers as a guide, not a diagnostic tool. Consumer sleep trackers try to provide detailed information about how well you navigated the sleep cycle the night before, but the results are by necessity limited by their reliance on movement. They can provide educated guesses on the quality of your sleep, but cannot provide definitive information.XIf using a sleep tracker gets you more focused on how much and how well you sleep, it provides a valuable service. Consider the results it provides as a starting point toward determining if you should seek a professional opinion about your sleep patterns.XTrust your body at least as much as the tracker, though. If you keep waking up groggy and tired but it says you’ve been sleeping like a baby, don’t use this as an excuse to avoid getting a professional opinion.

3Consider a professional sleep analysis by polysomnography. Regardless of what your sleep tracker is telling you, if you lie awake at night consistently or wake up tired and groggy despite what should be sufficient sleep time, you should seek a supervised sleep examination. Conditions like insomnia or obstructive sleep apnea can have severe health consequences.XFirst, consult your physician about your concerns and determine whether a professional sleep study is right for you.If a sleep study is advised, you will spend the night at a clinic and have a series of about 20 wired sensors attached to various parts of your body. Polysomnography sensors track body movement, eye movement, heart rate, breathing, and several other factors in order to derive a complete analysis of your sleep pattern. This information can be used by medical professionals to diagnose a range of sleep disorders.XPolysomnography in a clinical setting isn’t perfect, of course. You have to spend the night away from home with a bunch of wires attached to you, which can not surprisingly make it difficult to get a typical night’s sleep. However, at present, this is the “gold standard” for sleep analysis.