Heart Rate inaccurate during weight lifting

[BillYYC]

I have been using a Fitbit for over 8 years.  I upgraded from Charge 3 to Charge 4 about 3 months ago.  I have noticed that the heart rate monitoring is not as accurate as it was with the Charge 3.  After some research, I discovered that the Charge 4 just does not work as well as a chest strap monitor while lifting weights.  I'm very disappointed.  I wish I had never upgraded.  Does Fitbit plan to fix this in future models?  If not, this will be my last Fitbit since it can't accurately trace heart rate during weight lifting.

[JuanFitbit]

@BillYYC Nice to see you here. Thank you for your feedback and your message. 

Does the situation with the measurements just when you do weightlifting or with other activities?

How does it behave during the day?

See you around. 

[BillYYC]

The monitor seems to track HR during most other daily activities.  The problem is that when weight lifting, you have many moments during a 75 minute workout where your heart rate spikes due to the nature of lifting weights.  The Charge 4 doesn't seem to be able to keep up.  I saw a great comparison video between the charge 4 and a chest strap monitor and the chest strap monitor was able to manage the peaks in heart rate much better.  I certainly noticed a difference between the Charge 3 and the Charge 4.  On the Charge 3, I might have 10 minutes in peak and 35 minutes in Cardio but the same workout using the Charge 4 would show no time in peak and maybe 15 minutes in Cardio.  This means that my calories burned are also not being calculated correctly.

While I like the alarm capability and the reminders to move during the day, I have discovered that the Fitbit is not a particularly useful tool as a weightlifter - at least since the Charge 4.  It's doubtful that I will buy another Fitbit and when the Charge 4 dies (which it will, they all do), I will just switch back to my old Mickey Mouse analog watch.  

[JuanFitbit · Accepted solution]

@BillYYC , Nice to see you back. Thank you for your feedback and explaining the weight lifting routine and the situation. 

You can have a look at our feature suggestion board to see if someone has already posted an idea about the development for a chest strap, and leave your vote for it or leave your own feedback. 

In your case could be that the Charge 4 recognized your heart rate as another zone. eg. previously 180 bmp was recognized as Cardio and now the same amount of beats is recognized as fat burning or peak , due the better shape that you got. 

In that case I suggest you to edit and customize the heart rate zones. More information about this and the instructions can be found here: What are heart-rate zones? (please scroll down until you see CUSTOM ZONES for the instructions.)

Hope this helps

[BillYYC]

Thank you so much for the information.  This certainly explains the difference in Heart Rates between the Charge 3 and the Charge 4.  I was able to easily calculate my own numbers, however, they are pretty much meaningless.  The calculation of "Heart Rate Reserve" which is now used in all the other calculations is a ridiculous mathematical formula with no real meaning.  It is about as useless as BMI calculations.  I have found the new "Active Minutes" calculations similarly useless since I generate over 100 minutes with each workout.  These new numbers are a huge demotivator since it looks like I'm just "phoning in" my workouts.  I am attempting to maintain 80% of my maximum heart rate during my workouts.  Perhaps setting a custom zone will help, but I'm not optimistic.

While I would absolutely recommend the Fitbit for people just starting on their fitness journey, it has now morphed into a tool that is not at all useful for more advanced users.  Sadly, I still maintain this will be my last Fitbit, unless they decide to return to real data calculations or at least have the option to not use Heart Rate Reserve or Active Minutes calculations.  Again, I deeply regret trading in the Charge 3 for this horrible "improved" unit.

[JuanFitbit]

@BillYYC Nice to see you back. Thank you for your feedback. Really appreciate it. 

Regarding the Active zone minutes that the Charge 4 measures now. As you mentioned they are a bit different as the Active Minutes that are measured with the previous models. 

I suggest you to have a look at this, maybe this can clarify some of your doubts and confusions. What are Active Zone Minutes or active minutes on my Fitbit device?

Hope this helps.

[BillYYC]

Thank you for the clarification regarding Active Zone Minutes.  I was aware of how they worked as I looked it up when I first started using the Charge 4.  Since MRH is no longer being used in its raw form, the Active Zone Minutes is also inaccurate for my purposes.  Because these calculations are inaccurate, I have to assume that calories burned as calculated is also inaccurate.
Sadly, with the Charge 4, Fitbit has become a tool that no longer meets my needs and I will be switching to another brand.

[LizzyFitbit]

Hi there, @BillYYC.

Thanks for your continued feedback about the Charge 4, and your research about its features. Let me clarify that the calories burned are calculated based on your basal metabolic rate, your demographic, your activity and heart rate data. I understand how important it's for you to get accurate data from your tracker and I'm sorry for the inconvenience this has caused. We're constantly working on our devices, and feedback like yours certainly helps us to evaluate and improve the overall experience with them.

I appreciate you for taking the time to bring this to our attention, and please know you're always welcome back to the Fitbit family.

See you around.