Today we had an interval training with 150m full effort runs. At the beginning I made sure the FR245 was fastened strongly on my wrist. I started with HR of 110. For some reason the HR did not rise during the 20-30 second full effort run. Sometimes it even decreased. On the walk back at around half the distance it reached around 130. and then slowly decreased to 110-120 before we started the next interval.
After a few rounds I said this can't be true, the numbers I see on the watch don't make sense and for sure I could feel my pulse was much higher when I ended the intervals. One of my friends gave me his Apple watch. I put it on my other (right) wrist. And then it confirmed:
At the end of the intervals Apple watch showed 160 but Garmin showed 110-120.
At half the distance walking back the Apple showed that my HR decreased to around 135 and at that point the Garmin started to display also the same value until the beginning of the next interval.
So it looks like whenever I need it the most (high intensity training) the Garmin HR sensor gives me 40 beats less readings than the actual (let's call the Apple correct, it at least matches my subjective feeling)
BTW 2 days ago we did another intervals uphill, and the Garmin watch showed unbelievably low HR values as well.
This is a total shock to me, until last week I was convinced that the Garmin HR sensors are of the bests if not the best of their category. I actually compared the FR245's HR sensor with a HRM-SS strap and even there it looked that the watch wins (at least in the 1st 20 minutes of the excersize, when the strap displayed too low and random values)
Is there any setting I can tweak maybe to increase the responsiveness? I mean the Apple could in an instant show the huge changes and the Garmin was in a so big delay that it actually never could reach the peak HR, and confusingly it sometimes showed decrease when in fact I'm sure my hart rate went up.
