How to use your sleep data

Sleep expert says awareness is key

ANN ARBOR, Mich. – Millions of Americans are sporting fitness trackers these days. These devices track your activity, but they also collect data on your sleep.

We asked Dr. Cathy Goldstein, a neurologist at the University of Michigan Sleep Disorder Center, to share the best ways to use this information to get a better night's rest.

Goldstein is passionate about sleep.

"I sleep eight to nine hours at night, and it's a priority for me," Goldstein said. "Most people need at least seven to eight hours of sleep, but the reality is, you're not as productive of a person, you're not as happy of a person, and you're not as healthy of a person without sufficient sleep."

She cautions most activity trackers tend to overestimate our sleep time.

"The way these devices work is they determine wake versus sleep by when you're even moving, so supposed wake, or when you're asleep, so less movement, " Goldstein said. "As you can imagine, the problem is if you're laying there completely still, but awake, as happens through part of the night."

Goldstein said anything that makes you more aware of how much sleep you're getting can be helpful.

"If you're regularly clocking less than seven hours of sleep, there's a problem and you need to start devoting more time to sleep," Goldstein said. "They literally are giving you a wake-up call."

Lack of sleep and health factors

The data can also help you spot connections between lack of sleep and other health factors.

"If you're someone who tracks your weight, your exercise, your calorie intake, even your mood, you could use a sleep tracker, take a look at your sleep duration, and how it relates to those other outcomes," Goldstein said.

Goldstein said one of the most useful new features of some sleep trackers and smart phones is focused on helping you maintain a consistent sleep schedule. Keeping your bedtime and wake time the same, even on weekends, can dramatically improve your sleep.

"People can have something called 'social jet lag,' where you push your get-up times about two to three hours later on the weekends," Goldstein said. "So Sunday night, when you lay down, it's like you're flying from L.A. back to New York, so it's a big problem."

Occasionally, someone will come in to U of M's Sleep Disorder Center after noticing their activity tracker shows they're waking up a lot at night or some other unusual pattern. Likewise, if your activity tracker shows you are getting sufficient sleep, but you still don't feel rested, Goldstein says you may be suffering from a sleep disorder, and should see your doctor or a sleep specialist.

Goldstein said most people these days are so sleep-deprived that increasing your sleep time, even a little, can have an immediate impact on your mood and alertness.  It literally happens overnight.


Ultimately, Goldstein says it's not data, but dedication, that will improve your sleep the most.

"Spend eight hours in bed at minimum devoted to attempting sleep," Goldstein said. "Avoid bright light, particularly that from electronics, after sundown, before bedtime, and wake up at the same time every day, even on the weekends, to stabilize that internal clock. That works better than any pillow, any mattress, any app, or any wearable on the market in improving your sleep."

To learn about common sleep disorders, click here.