Have you considered that you may just be an incredibly gifted athlete?

The parent comment said "off", which I took to mean that he measured his heartrate manually and compared to the device readout.

This is what I meant.

The ecg monitors built into the precor bikes and counting my wrist pulse for 30 seconds and doubling are generally within 2-4 bpm of each other. My fitbit consistently measures 130-ish when the truth is 175-ish per the above two methods (my cardio hr target).

Same here with Precor. Fitbit hr says 110 while treadmill says 130. Oddly when I got up to 145 on the treadmill the Fitbit read the same. I'm not sure which one to believe. probably not the Fitbit as I've heard about the lawsuit.