Validation of photoplethysmography as a method to detect heart rate during rest and exercise

Despite their enhanced marketplace visibility, validity of wearable photoplethysmographic heart rate monitoring is scarce. Forty-seven healthy participants performed seven, 6-min exercise bouts and completed a valid skin type scale. Participants wore an Omron HR500U (OHR) and a Mio Alpha (MA), two commercial wearable photoplethysmographic heart rate monitors. Data were compared to a Polar RS800CX (PRS). Means and error were calculated between devices using minutes 2–5. Compared to PRS, MA data was significantly different in walking, biking (2.41 ± 3.99 bpm and 3.26 ± 11.38 bpm, p < 0.05) and weight lifting (23.30 ± 31.94 bpm, p < 0.01). OHR differed from PRS in walking (4.95 ± 7.53 bpm, p < 0.05) and weight lifting (4.67 ± 8.95 bpm, p < 0.05). MA during elliptical, stair climbing and biking conditions demonstrated a strong correlation between jogging speed and error (r = 0.55, p < 0.0001), and showed differences in participants with less photosensitive skin.