Heart rate during exercises fake?

[Skennedy926]

So for the last few days I’ve been trying to monitor my heart rate during exercises more. And what I noticed is that when I start an exercise program in the Fitbit inspire HR, all of a sudden my heart rate jumps from resting to fat burn zone, even when all I’ve done physically is turn the watch to that exercise mode. I tried this on several occasions, even turned it on while not moving a muscle and sitting still, and still it jumped into fat burn within seconds of me turning on the program. Why should that be happening? 

[Baltoscott]

@Skennedy926 — I have not noticed this but will check. How big of a change in HR are you seeing?  

[Skennedy926]

I am noticing it jump, on average, 30 bpm, again, when I’m not physically
moving. Yesterday during a 5 minute period it fluctuated between around 80
and 120 3 times, when just before that my heart rate reads around 60. The
only change was me turning on the “weights” exercise mode.

[Baltoscott]

Hey @Skennedy926  — I tried replicated your problem using the weights exercise mode on my Inspire HR, but did not notice any change in HR due to simply entering the exercise mode.  

I suggest you try restarting your HR, and if that doesn’t address the problem contacting support.

[mbY]

I wouldn't say fake (I hope), but I do a crazy Saturday group exercise -- step aerobics (yes, thankfully still offered in my area) -- and look at my heart rate when I'm pushing it and can feel my heart pounding, it is rarely at peak rate.   Also, at the end of 40 - 45 minutes vigorous, 10 or so warm up, the total calories are lower than expected (oops, calories is another forum 😉).   I use my fitbit as a guide and a data collector and have had fun with it, since I got in Dec 2018.  Accuracy could use some work.  I hope not fake (although sometimes my sleep record is unlike what i experienced also -- but that's another topic!)  🤔😁

[Ryefield]

Yes, I'm noticing this too. With any exercise, even light exercise, my heart rate jumps to fat burn right away. This could be walking, or having an intense conversation. I am monitoring my heart rate manually, and the FitBit is reading approx. 2X what the actual rate is. 

Annoyingly, it tells me to keep exercising constantly. 

When my heart rate is lower, calmer, the read is very accurate. But, with any exertion happens, when there is any load on my heart, then the read is WAY higher than the actual value. usually 2X.

I think the FitBit is reading both the diastolic and systolic as two beats.

I have a resting HR of 45 bpm