How useful is a wearable for analysing sleep quality?
Comparison with a chest strap HR-monitor
July 16, 2019 - Willem L. Middelkoop
Sleep monitoring is a popular feature of many smartwatches and wearables. Devices like Fitbit, Withings, Apple Watch and Biostrap analyse biometrics during your sleep. These wearables are worn on the wrist and use optical sensors to capture your heart rate. I wondered how the optical sensors would compare to a high resolution chest strap HR-monitor.
Continue reading![Apple Watch uses an optical sensor to perform its automated heart rate monitoring](/blog/2019-07-16_limitations-of-sleep-tracking-using-a-wearable/images/i_00_Apple-Watch-uses-an-optical-sensor-to-perform-its-automated-heart-rate-monitoring_500px.jpg)
![Combining heart rate measurements with movement data from a gyroscope sensor](/blog/2019-07-16_limitations-of-sleep-tracking-using-a-wearable/images/i_05_Combining-heart-rate-measurements-with-movement-data-from-a-gyroscope-sensor_500px.png)
![Heart rates measured by Apple Watch reveal that measurement is only done once every 5 minutes](/blog/2019-07-16_limitations-of-sleep-tracking-using-a-wearable/images/i_01_Heart-rates-measured-by-Apple-Watch-reveal-that-measurement-is-only-done-once-every-5-minutes_500px.png)
![Heart rate during my experiment night as captured with the optical HR sensor (top) and chest strap (bottom)](/blog/2019-07-16_limitations-of-sleep-tracking-using-a-wearable/images/i_04_Heart-rate-during-my-experiment-night-as-captured-with-the-optical-HR-sensor-top-and-chest-strap-bot_500px.png)
![Wahoo TICKR uses conductive pads in its strap to capture your heart's electric activity directly](/blog/2019-07-16_limitations-of-sleep-tracking-using-a-wearable/images/i_02_Wahoo-TICKR-uses-conductive-pads-in-its-strap-to-capture-your-heart-s-electric-activity-directly_500px.jpg)
![Wahoo TIKR (left) captures more data per minute than Apple Watch (right) per hour!](/blog/2019-07-16_limitations-of-sleep-tracking-using-a-wearable/images/i_03_Wahoo-TIKR-left-captures-more-data-per-minute-than-Apple-Watch-right-per-hour_500px.png)