I have done another experiment to prove that it’s the HRM and not my heart which caused the scary spikes. Today I deliberately ran slow with a target strike rate of 80. I have lots of experience that at this stride rate my HR should be near 150 or so, this proved to be correct for the first 7k or so. Ignored the pace I followed a tall guy who was just brisk walking in front of me.
At around 8k spikes came again as can be seen below it peaked at 190 so I cleaned the chest belt then I dropped to 164-175-149. My heart just won’t slow down that fast. I then ramped up my stride rate from 80 to 90 …. wow my pace was near 6 min/k while HR was steady at 160.
From below it’s very obvious that HR reading started to look weird near 8k and steadied down even if I run faster.
The key findings are:-
- RH is low say 50% or so
- Windy that could dry out sweat quicker
- Not hot, not sweating enough
- A layer of dried sweat can be formed at 8-9k
I think Garmin’s HRM is more sensitive than miCoach’s as I never had to wet the contacts after putting the chestbelt on even if weather is dry. I only had a few cases of HR spikes so far when using miCoach.
By the way I felt very easy bouncy and light at the last km running at high stride rate.