When I look at the Ios Garmin Connect or using the web interface I am geting the attached picture as my heart rate.
It seems that I do have a steday heart rate for the whole day but the picture was taken at 11:20 local time and it looks that when I was returining from my morning run my heart rate went crazy!
I am using a fenix 5x with the lates software version and when I run I am using a Garmin HR strap, the one with the red oval thingy on it. On the watch everything looks normal, only on the Iphone or on the web I get this great graphic.