The Accuracy and Validity of iOS-Based Heart Rate Apps During Moderate to High Intensity Exercise

Authors

Alexa M. Bouts, Ohio Northern UniversityFollow
Lauren Brackman, Ohio Northern UniversityFollow
Elizabeth Martin, Ohio Northern UniversityFollow
Adam M. Subasic, Ohio Northern UniversityFollow
Edward S. Potkanowicz, Ohio Northern UniversityFollow

Abstract

International Journal of Exercise Science 11(7): 533-540, 2018. People use their smartphones for everything from web browsing to tracking fitness metrics. However, it is unclear whether smartphone-based apps that use photoplethysmography to measure heart rate are an accurate or valid measure of exercise intensity. Purpose was to determine the accuracy and validity of two iOS-based heart rate monitors, Runtastic Heart Rate Monitor and Pulse Tracker PRO by Runtastic (Runtastic) and Instant Heart Rate+: Heart Rate and Pulse Monitor by Azumio (Instant Heart Rate), when compared to the electrocardiogram (ECG) and Polar® T31 uncoded heart rate monitor from moderate to vigorous intensity exercise. Participants were 15 male and female regularly active college students. Pre-exercise heart rate and blood pressure were recorded and then participants exercised on a stationary bike at a pedal rate of between 50-60 rpms. After completing a warm-up stage at 40% of age estimated maximum heart rate (AEMHR), exercise intensity progressed from 50% of AEMHR through to 85% of AEMHR in eight, 5-minute stages. At the end of each stage, and having achieved steady-state, heart rates were recorded from each apparatus. After completing the final stage, participants completed a cooldown at 40% of their AEMHR. Post-exercise heart rate and blood pressure were also recorded to ensure full recovery to baseline. There was a strong positive correlation between the Polar® monitor and the ECG during all stages. However, there were not strong correlations for either of the smartphone-based apps at any time point. Although there were weak correlations between the smartphone-based apps and ECG and Polar®, further studies need to be conducted to determine if inaccuracy is due to user error (finger placement, finger temperature, etc.) or the technology behind the apps.

Recommended Citation

Bouts, Alexa M.; Brackman, Lauren; Martin, Elizabeth; Subasic, Adam M.; and Potkanowicz, Edward S. (2018) "The Accuracy and Validity of iOS-Based Heart Rate Apps During Moderate to High Intensity Exercise," International Journal of Exercise Science: Vol. 11 : Iss. 7, Pages 533 - 540.
DOI: https://doi.org/10.70252/QWRT8315
Available at: https://digitalcommons.wku.edu/ijes/vol11/iss7/4