Whe Want to Test the Accuracy of Consumer Grade Heart Rate Monitors (HRM), How Shall We Proceed?

Last Updated on September 30, 2022 by pg@petergamma.org

Many reviewers of consumer grade HRMs and sports scientists use the Polar H10 chest strap as a reference device for their studies. But the Polar H10 will have a successor, and there will be successors of the successor, so we have to change the reference device, if we want to be keep up with the newest and potentially most accurate device.

Some accuracy studies determine the signal quality of the HRM, as in the following paper of the Swiss Federal Institute of Sports in Magglingen:

90.10 Scientific papers which determine the signal quality of HRMs

Research and medical grade ECG devices are known to be highly accurate are not so often replaced by newer models than sports chest straps. And it is hard to convince clinicians and research scientists to use the Polar H10 as their reference device instead of an ECG device. High quality ECG devices have proven the be more accurate than the Polar H7 chest strap, with activities with little movements. Some ECG devices are used with high-quality ECG toolboxes, which are generally not used with the Polar H10 chest strap. If we have already a high quality ECG device, which is not movement artifact-free, we can try to test the protocol of this paper:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6732081/

In a previous paper of this group of cardiologist Milind Y. Desai from Cleveland Clinic Ohio, ECG was monitored on a high quality clinical ECG system. The ECG based heart rate was determined by visual assessment under direct supervision by a cardiologist. In this paper, ECG based heart rate was determined by visual assessment by trained research personnel. The authors used a 3 lead ECG, wich is according to the paper considered the gold standard for heart rate measurement.

They tested the accuracy of HRMs on the treadmill with a speed up to 14.48 km/h (4 – 9 mph).

If we observe problems with ECG movement artifacts, we can try to use HeartPy: A novel heart rate algorithm for the analysis of noisy PPG signals and very noisy ECG signals:

https://scholar.google.com/citations?user=OOhuA6gAAAAJ&hl=de&oi=sra

and see if it works.

If our budget allows, we can buy a Equivital sensor belt with Adinstruments LabChart software, which is sold as noise and motion artifact-free ECG:

90.02 Research & medical grade ECG devices which some of those were used to study the accuracy of consumer grade HRMs in different papers

A device which costs this much and is sold as noise and motion artifact free ECG device, should be noise and movement artifact free. If not, we can complain at Adinstruments.

If your budget does not allow, we can build our own mobile ECG device, based on OpenBCI and HeartPy:

ECG from OpenBCI with 3 & 5 electrodes with up to 4 digital channels with noise reduction

and test it.

We can also buy an iWorx recorder, use the iWorx ECG toolbox, and if ECG motions artifacts occur, we can adjust it with the ECG toolbox, or try HeartPy with this device. Or we can do the same with any other brand of ECG devices which we prefer.

At the end, we come back to the answer of the g.tec medical support, that they do not know of any manufacturer of ECG devices, which solved the problem of ECG motion artifacts.

Adinstruments sells one. But we do not know of any papers which tested the Adinstruments Equivital with LabChart software and demonstrated, that this device is a noise and motion artifact free ECG device.

The Equivital has only 2 leads as shown in this table:

90.02 Research & medical grade ECG devices which some of those were used to study the accuracy of consumer grade HRMs in different papers

This paper of the group of Cardiologist Milind Y. Desai, Cleveland Clinic Ohio:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6732081/

defines a 3 lead ecg system as a gold standard for HR measurement, but the Equivital Sensor belt is only a 2 leads ECG.