Currently accepted at: JMIR Formative Research
Date Submitted: May 2, 2026
Date Accepted: Nov 11, 2026
This paper has been accepted and is currently in production.
It will appear shortly on 10.2196/100120
The final accepted version (not copyedited yet) is in this tab.
Impact of Motion Artifact on the Accuracy of Wrist-Worn Photoplethysmography Devices Across Exercise Modalities: A Study on Cycling and Treadmill Workloads
ABSTRACT
Background:
Consumer-grade photoplethysmography (PPG) wearables provide convenient heart rate (HR) monitoring, with wrist-worn devices widely adopted due to their affordability and accessibility.
Objective:
This study evaluated the accuracy of four wrist-worn devices (Fitbit Inspire, Garmin Vivosmart, Xiaomi Mi Band, and Amazfit Band) across rest and different exercise modalities with different levels of arm motion.
Methods:
Thirty participants volunteered and consented to participate in cycling and treadmill exercise protocols. HR values were recorded at 15-s intervals simultaneously using each device and a criterion electrocardiogram (ECG). Validity was assessed using the Pearson Moment Correlation Coefficient, Bland-Altman analysis, and mean absolute percent error (MAPE).
Results:
While Garmin outperformed Xiaomi during the treadmill exercise, both devices (Garmin and Xiaomi) demonstrated high agreement with ECG during cycling (r = 0.95 and 0.98) and treadmill exercise (r = 0.96 and 0.94), with small mean biases (-1.25 and -1.68 beats/min) and narrower limits of agreement compared to the other two devices. Although Amazfit and Fitbit devices showed good correlation for both exercise modalities, larger mean biases were observed, particularly during treadmill exercise. All devices achieved MAPE <10% across conditions, except Fitbit, which exceeded the validity threshold during treadmill exercise (MAPE = 11%).
Conclusions:
PPG-based HR accuracy is affected by motion artifact. While devices exhibited acceptable accuracy under low-level arm motion conditions, accuracy varied during high-level arm movement exercise. These findings provide a data-driven reference for consumers and practitioners when selecting wrist-worn devices for heart rate monitoring across different exercise modalities. Clinical Trial: NA
Citation
Request queued. Please wait while the file is being generated. It may take some time.
Copyright
© The authors. All rights reserved. This is a privileged document currently under peer-review/community review (or an accepted/rejected manuscript). Authors have provided JMIR Publications with an exclusive license to publish this preprint on it's website for review and ahead-of-print citation purposes only. While the final peer-reviewed paper may be licensed under a cc-by license on publication, at this stage authors and publisher expressively prohibit redistribution of this draft paper other than for review purposes.