Dr. W. Chris Winter, Men’s Health sleep adviser and author of The Sleep Solution: Why Your Sleep Is Broken and How to Fix It said that the data sleep tracking devices provide can be useful and that the trackers do a good job of providing insight into a person's sleep patterns over time, such as the total time a person's probably sleeping. However Winter also said that trackers can struggle with determining the stage of sleep a person is in. Dr. Isha Gupta, a neurologist at IGEA Brain & Spine said that sleep tracking devices offer a good way to gain an overall idea of how often a person wakes up at night, how long it takes a person to fall asleep, and data that can help a person tweak their habits, such as setting an earlier bedtime or keeping their bedroom cooler. However, according to Gupta, there's concern that trackers overestimate sleep when a person's body is still and the person's heart rate has slowed, but the person is not actually sleeping.
