Gadgets that monitor our coronary heart charges primarily based on a measurement on the wrist are fairly prevalent these days, together with Fitbit, Garmin watches, and Apple Watches. There are additionally units that promise extra refined outcomes comparable to coronary heart fee variability from Whoop. These units then inform us insightful issues about our current exercises or our exercise all through the day, how lengthy we must always recuperate earlier than our subsequent exhausting exercise, and even how effectively we’re sleeping.
The difficulty is that the accuracy of the info all this data relies on is suspect. I first seen this again after I had a Fitbit. It will typically learn larger than I suspected was appropriate, primarily based on how exhausting I felt I used to be working. The identical is now true of my Garmin watch. I may be simply warming up, and it’ll inform me my coronary heart fee is within the 130’s, which I do know can’t be true as a result of I’d actually be huffing and puffing. I just lately put it to a check. I occur to even have a Polar H10 coronary heart fee strap. And a separate machine (my Garmin bike pc). So on the identical journey, I made certain my watch was not paired to the strap, and solely had wrist information obtainable for coronary heart fee. My bike pc was paired to the strap so it was a chest-based measurement. In such a comparability, we anticipate the chest measurement to be extra correct, however I used to be blown away how a lot the 2 differed. The 2 charts from a three-hour journey are proven beneath. The max coronary heart fee from the wrist measurement was 41 beats two excessive, and suspiciously confirmed up after I was simply warming up. There are numerous different locations within the charts the place the wrist outcomes are simply not proper.
I had been studying up on optimum coaching strategies primarily based on coronary heart fee, all of which sound fairly scientific. However I now know that the info I used to be basing this on was untrustworthy (I normally simply use wrist-based as a result of it’s an additional step to placed on the strap). Sooner or later I’ll make sure that I exploit the strap after I actually wish to examine coronary heart fee. I can even put extra belief in how my exercise feels (perceived degree of exertion).
