Accuracy of maximum heart rate

I'm sure this has been asked before, but I'm just curious. I'm 52 year old and according to the usual formulas, I should have a maximum heart rate of around 168 bpm. However, my forerunner 45 regularly gives a reading of 185 (and once even 190). Can this be accurate? 

  • Sure, if you're fitter than the average 52 old. I'm a 66 yo avid cyclist and my max hr is around 176. Only caveat is I typically use a chest monitor when I'm riding which is considered more accurate and my FR45 always reads much lower. 

  • Does the Garmin's report of your resting HR match what you measure with a stopwatch? If so, and if the HR trace during exercise looks OK (fairly smooth curve, consistent within and between sessions, increasing and decreasing where you'd expect it to) then it's probably working fine.

    Interesting what  says, though. From my low level of understanding, I can't see why any heart rate monitor should be inaccurate as long as it can detect a pulse. I guess there's an issue of averaging, though. If you measure over too long a period then the reading won't be very responsive, while if it's too short you may get jumpy readings and false spikes.

    "The usual formulas" are no more than guides as far as I can see. I'm 60, so (220 - age) = 160, but various calculators here: https://goodcalculators.com/heart-rate-calculator/ give figures up to 172. Somehow I find it hard to imagine that fitness level and resting HR don't come into it.