Key result
Apple Watch and Fitbit heart rate accuracy declines vs ECG as exercise intensity increases.
Why the study?
Heart rate measurements from the Apple Watch and Fitbit Charge HR 2 devices had not been directly compared with electrocardiogram across different exercise intensities.
Do heart rate measurements by the Apple Watch and Fitbit Charge HR 2 accurately reflect ECG measurements across different exercise intensities in young adults?
Observational (n=30)
Do heart rate measurements by the Apple Watch and Fitbit Charge HR 2 accurately reflect ECG measurements across different exercise intensities in young adults?
The accuracy of real-time heart rate monitoring by the Apple Watch and Fitbit Charge HR 2 decreases as exercise intensity increases, though the Apple Watch demonstrates lower relative error rates overall.
No takes yet. Share an insight, caveat, or question.
Accuracy limitations at high intensities warrant caution in athletic monitoring; hypothesis-generating and leaves open prospective validation needs.
Thomson et al. (2019) conducted an observational in Young adults (n=30). Apple Watch and Fitbit Charge HR 2 vs. Electrocardiogram (ECG) was evaluated on Concordance correlation coefficient (CCC) and relative error rates (RER) of heart rate measurements. Heart rate monitoring accuracy by the Apple Watch (RER 2.4-5.1%) and Fitbit Charge HR 2 (RER 3.9-13.5%) compared to ECG declined as exercise intensity increased.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: