@gtung3388 except for my first run, I’ve not noticed a difference in my HR, and definitely no jumping around. I do use a nylon strap so not sure if that has helped?
But as others have said, if you want an accurate HR then you’ll have to use a strap. This morning’s run is below, quite consistent with the inclines/declines - the dips are when we’ve stopped.
e05fd3ed-09cf-43a2-9c06-a1bda9148e51-image.png