The Accuracy of Wrist-Worn Heart Rate Measurements: A Comparison between a Consumer and Research Grade Device

This case study evaluates heart rate (HR) measurements taken from a consumer grade and a research grade wrist-worn device. A healthy male volunteer performed a treadmill protocol of three five-minute stages (walking at 4km/h, jogging at 7km/h and running at 10km/h) while wearing an Empatica E4 and Fitbit Alta HR. A Polar H10 heart rate sensor was used as the criterion measure. As the intensity of exercises increased, the E4 device was increasingly inaccurate. The Fitbit device overestimates HR while jogging yet accurately measures HR during treadmill running. Further data are required before definitive conclusions can be made.