(WILX/NBC) - Millions of Americans are sporting fitness trackers these days.
These devices track your activity, but they also collect data on your sleep.
Doctor Cathy Goldstein is passionate about sleep. She gets eight to nine hours a day.
She's a neurologist at the University of Michigan Sleep Disorder Center.
"You're not as productive of a person, you're not as happy as a person, and you're not as healthy as a person without sufficient sleep," Goldstein said.
She cautions most activity trackers tend to overestimate our sleep time.
But Goldstein says anything that makes you more aware of how much sleep you're getting can be helpful.
"If you're trying to track your weight, your calories, your exercise, even your mood… you could use a sleep tracker, track your duration, and how it relates to those other outcomes," Goldstein said.
Goldstein says one of the most useful new features of 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.
"Spend eight hours at a minimum attempting at sleep. Avoid bright light particularly that from electronics before sundown and wake up at the same time every day even on the weekends to stabilize that internal clock. That works better than any pillow, mattress, app or wearable on the market in improving your sleep" Goldstein said.
Experts also say that if your activity tracker shows you are getting sufficient sleep, but you still don't feel rested, you may be suffering from a sleep disorder and you should see your doctor or a sleep specialist.