Reliability of Wrist Coronary heart Fee Displays – BionicOldGuy

Units 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 subtle outcomes resembling 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 get well earlier than our subsequent arduous exercise, and even how effectively we’re sleeping.

The difficulty is that the accuracy of the information all this data relies on is suspect. I first observed this again once I had a Fitbit. It might usually learn increased than I suspected was right, primarily based on how arduous 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 gadget (my Garmin bike laptop). 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 laptop was paired to the strap so it was a chest-based measurement. In such a comparability, we count on 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 once 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 information 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 be certain I take advantage of the strap once I actually wish to examine coronary heart fee. I will even put extra belief in how my exercise feels (perceived stage of exertion).