Iowa Sleep Blog

What Can My Personal Fitness Monitor Tell Me about My Sleep?

Tuesday, May 27, 2014

A quick note before answering: our free webinar on use of a personal fitness monitor is coming up! The webinar is from 12-12:30 p.m. on Thursday, June 5. Register at Watch from the conveniences of your office or at home!

Back to the question

Personal fitness monitors—including the Fitbit, the Jawbone UP and the Nike Fuel Band—are big business. Sales in the United States totaled approximately $290 million in 2013. This year, sales are expected to double.

These devices all have a common sensor—an accelerometer—that tracks motion in three dimensions: up/down, side to side and back and forth. When sleep is being monitored, the sensitivity of the accelerometer is enhanced.

The theory behind this is that movement equals wakefulness and prolonged lack of movement indicates sleep.

When measuring sleep, the Jawbone UP, for example, needs to be engaged into sleep mode so that the accelerometer is more sensitive. Once data from the wrist band is downloaded to the mobile app, information about how well you slept then displays how much time was spent in Light Sleep, Deep Sleep and Awake. The Jawbone UP will also record how much time you spent in bed, how long you slept and how many times you woke up.

Benefits and shortcomings

These types of devices can encourage healthy people who simply want to sleep better to make changes to improve their sleep by giving them a more complete awareness of how long they are sleeping at night. This is important because many people are more deprived of sleep than they realize.

Even so, experts worry there may be a danger in consumers putting too much trust in these devices to accurately monitor sleep, especially users who have sleep disorders.

Devices that track sleep with only an accelerometer cannot provide much insight into the quality of sleep experienced. For example, a person with sleep apnea may stop breathing 300 times a night, but this would not be detected. Sleep apnea and other sleep disorders are best detected and treated by making an appointment with a board-certified sleep physician and undergoing a comprehensive sleep study.

Don’t forget our FREE webinar!

Find out more about the pluses and minuses of personal fitness monitors during a free webinar conducted by Dr. Stephen Grant of Iowa Sleep. The webinar will take place from 12-12:30 p.m. on Thursday, June 5. Register at