The purpose of this study was to evaluate the accuracy of the Polar M600 optical heart rate (OHR) sensor compared with ECG heart rate (HR) measurement during various physical activities.
Thirty-six subjects participated in a continuous 76-min testing session, which included rest, cycling warm-up, cycling intervals, circuit weight training, treadmill intervals, and recovery. HR was measured using a three-lead ECG configuration and a Polar M600 Sport Watch on the left wrist. Statistical analyses included OHR percent accuracy, mean difference, mean absolute error, Bland–Altman plots, and a repeated-measures generalized estimating equation design. OHR percent accuracy was calculated as the percentage of occurrences where OHR measurement was within and including ±5 bpm from the ECG HR value.
Of the four exercise phases performed, the highest OHR percent accuracy was found during cycle intervals (91.8%), and the lowest OHR percent accuracy occurred during circuit weight training (34.5%). OHR percent accuracy improved steadily within exercise transitions during cycle intervals to a maximum of 98.5% and during treadmill intervals to a maximum of 89.0%. Lags in HR calculated by the Polar M600 OHR sensor existed in comparison to ECG HR, when exercise intensity changed until steady state occurred. There was a tendency for OHR underestimation during intensity increases and overestimation during intensity decreases. No statistically significant interaction effect with device was found in this sample on the basis of sex, body mass index, V˙O2max, skin type, or wrist size.
The Polar M600 was accurate during periods of steady-state cycling, walking, jogging, and running, but less accurate during some exercise intensity changes, which may be attributed to factors related to total peripheral resistance changes and pulse pressure.
1Canadian Sport Institute Calgary, Calgary, Alberta, CANADA; 2Research Computing Services, Information Technologies, University of Calgary, Calgary, Alberta, CANADA; and 3Faculty of Kinesiology, University of Calgary, Calgary, Alberta, CANADA
Address for correspondence: John F. Horton, M.Sc., Canadian Sport Institute Calgary, Room 125 Olympic Oval, 2500 University Drive NW, Calgary, Alberta, Canada T2N 1N4; E-mail: email@example.com.
Submitted for publication April 2017.
Accepted for publication July 2017.