On the last run, harder than normal indeed, I had a max heart rate of 195 ! I was also constantly over 180, even if I did not feel so exhausted. The run lasted about 35 minutes and for the last 15 minutes I was constantly over 180.
I am 35 years old, my max heart rate should be around 185 with the 220-age calculation method. Is my Garmin vivoactive not so accurate? Or is it normal for people like me to sometimes have a greater max heart rate than average?