DC Rainmaker and others, see discussion here: https://www.dcrainmaker.com/2021/02/polar-verity-sense-optical-hr-sensor-band-in-depth-review.html The consequences are, that we are fed up discussing about ANT+ and BLE sensors, too, and how to use those for physiology. For us personally, papers as this one are more interesting: which we hope that they will published sooner or later.