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How accurately do fitness trackers monitor sleep?As the "quantified self" craze continues, fitness trackers have us obsessing over not only how active we are but also how soundly we're sleeping. How do the devices stack up against clinical sleep studies though? CNET's Sumi Das visits the Stanford Sleep...
[MUSIC] Fitness trackers not only count our steps and calories burned, many provide sleep stats. But can you trust that data? We asked an expert at the Stanford Center for Sleep Sciences. The reason why these devices are good is because it puts greater emphasis on. Sleep. Most adults in the U.S. are actually somewhat sleep deprived. But are they accurate? The devices offer relatively little data as compared to the gold standard for measuring sleep, polysomnography. Polysomnography is a collection of different. Physiologic measures that we use to define and characterize sleep. We start with EEG, which are little electrical wires tha measure your brainwaves. And it doesn't stop there. Prepping a patient for polysomnography takes close to an hour. It also includes measures like. A snore mic that'll be on your neck. Inside your nose and over your nose and your mouth to kinda record your breathing. Belts around your chest and your abdomen that will also record your breathing. Patients stay over night for these sophisticated sleep studies which require a slew of equipment. From muscle monitors to EKG machines. Fitness trackers, on the other hand, use accelerometers. They're not actually measuring sleep, they're measuring an indirect approximation of sleep through movement. In order to make these estimations of deep or light sleep, they are probably using an algorithm that. Takes into account the relative amount of movement that a person is having over the course of the night. Fitness devices have another key flaw. They can't precisely measure sleep latency. The time it takes to fall asleep. Both of them are really not very good at telling how long you're awake in the middle of the night. And your, your total sleep time relative to the amount of time that you're in bed. Still, there's value in paying more attention to your sleep habits. A lack of sleep can affect mood, ability to concentrate, and more. Fitness trackers motivate us to get our steps in, but they could help us get our z's in too. In Redwood City, California, I'm Sumi Das, CNET. COM for CBS News.