Seems to happen when the heart goes over a certain rate
It may actually be the filter that's applied is too narrow so it's filtering out the higher frequency... But realistically what we need is a bunch of data files so we can make informed decisions about it.
With no accelerometer input, it's also possible that while running the Bangle is picking up your running pace rather than heart rate.
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
It may actually be the filter that's applied is too narrow so it's filtering out the higher frequency... But realistically what we need is a bunch of data files so we can make informed decisions about it.
With no accelerometer input, it's also possible that while running the Bangle is picking up your running pace rather than heart rate.