Last Updated on May 22, 2022 by pg@petergamma.org
The Polar sensor logger app from Jukka Happonen:
records R-R peaks which are required for instance for Respiratory Rate Estimation in Matlab:
https://www.mathworks.com/matlabcentral/fileexchange/55289-respiratory-rate-estimation
The Respiratory Rate Estimation project has different datasets and is already validated with many subject.
The Polar H10 has already been validated for running activities, inaccuracy, 5.5.
I suppose the inaccuracy for practicing meditation (at rest) is lower than during running. Therefore I suppose the Polar H10 chest strap could be a useful tool to calculate respiratory rate during practicing mediation.
It is also possible to valdidate Polar H10 (or a Fenix 6) manually. Programm an (old) Garmin watch to vibrate every minute, and count the number of breath you take until the next vibration. You get a set of datapoints with a datapoint each minute.