Incorrect Heart Rate tracking

[SunsetRunner]

Hi there, I got given a Fitbit Sense 2 for my birthday the 3rd Jan. I was extremely excited as it sounded amazing. However the heart rate tracking during workouts is way way off. I have been a personal trainer for over 20 years and can judge my heart rate while exercising pretty accurately. This sense 2 jumps around and gives readings way lower. This makes me doubt the watch and I now feel it’s useless!! Can I return it or is there something I can do? 

[t.parker]

HR tracking is not the strongest point of Sense 2 and there isn't much you can do about it.

[SunsetRunner]

It’s so annoying as lost complete respect for the watch now!!!! I wonder if a versa would be better?? 

[t.parker]

If you mean Versa 4 then no, it's the same sensor and tech and experience is similar. Other Versa models - I don't know. I require very accurate HR and go with chest strap (wouldn't trust any Fitbit or in general, wrist HR on that).

[SunsetRunner]

Hi, thanks for your reply. Yes I thought maybe they new Versa 4 used a similar technology. Wont move to that then. 

[BarefootRunner]

I find the Sense 2 a poor performing product also. It does not read HR accurately. I just checked my HR 3 ways and compared to the sense numbers. I got 68 and the Sense got 81. I am totally frustrated. I had the Sense 1 and it was the same so I switched to the Charge 5 and it was much more accurate. I thought perhaps they had fixed this problem, but it seems they keep pushing out the same crap…

[BarefootRunner]

The unfortunate thing about this is that HR feeds into many of the other tracking features, I.e. zone minutes HRV, etc….. it also affects the stress readings which is the big seller on this product so it makes it useless. HR readings need to be accurate for the other elements to work.

[t.parker]

@BarefootRunner during activities Sense 2 is horribly inaccurate but I wouldn't be so harsh on it when in rest (especially, during sleep). You may be interested in this analysis I've done over a period of month against Garmin device. The conclusion is based on assumption that neither device is correct on its own but if there is a corelation in data between both devices then it indicates a level of certain correctness (or both devices are wrong despite agreeing on something but this is very unlikely to happen). I've been observing that corelation on daily basis with Sense 2 and Garmin Fenix 7. That idicates certain degree of accurcy during sleep and since we talking about HRV, which is harder to measure than HR (needs higher data resolution) it isn't bad result. My only issue with Fitbit's  HRV is that it's rushing to change my base line and normal range too quickly which then affects other metrics. I've been injured recently, ill and overtrained. That lower my HRV (on all devices including tested with chest strap and EliteHRV app) significantly for a longer period of time and now it's all coming back to normal. For Fitbit, it's almost always in normal range because it just lowered my baseline. That prevents detecting being strained and will affect other metrics. The error isn't however in readings but in the methodology of processing them.

[BarefootRunner]

The thing is, the first part of HRV is “heart rate” and if it isn’t reading your HR accurately, then it doesn’t matter how many other variables it is reading. It is dependent upon measuring HR accurately.

HR is a huge factor in heath and cannot be downplayed as a necessary measurement.

Lastly, Google pitches the Sense as an amazing aid to health and fitness, but just does not deliver. The other Fitbit trackers do this better, selling a product without assuring it works properly is just bad business.

[Emccar93]

Hi!

So strange I just came on here due to the same thing, i had the versa before and I felt like it was some what accurate when I was in peak/ cardio but now with the sense 2 I know personally that I'm in peak or cardio and it says the below zone / fat burning ... I've tried wearing it tighter/ looser, moving it up my arm a bit etc and it doesn't seem to be doing anything 🤔

[t.parker]

@BarefootRunner yes but HR accuracy seems to depend on the noise coming from the motion. During sleep you almost don't move hence the accuracy of HR is not affected and HRV seems to work alright, too. Sense 2 isn't inaccurate all the time. Measuring HRV during movement is possible but requires better equipment (like chest strap). The problem is that you can't tell whether data is or isn't accurate without crosscheking it against accurate reference. I do test it against other equipment hence my opinion. If you opened the link I gave you, this is based on data not "feeling" and data speaks for itself. You can also find plenty of other tests I've done for activities to see level of accuracy (or in this case - inaccuracy). Sense 2 (and original Sense) seem to be very sensitive to motion which greatly affects HR. Daily steps tracking and sleep tracking can be done. Exercise tracking - get another watch (ideally, one that can also utilize external sensors).

[Emccar93]

Really good point, it seems to be a little more accurate when I'm doing something with less motion like weights but when I'm doing hiit type work outs and moving a lot, that seems to be when it's going into lower zones. Thanks for the advice 😊

[SunsetRunner]

Hi there, I feel your frustration. Very annoying when you purchase something and it doesn’t do what it’s meant to!!!!! 

[Emccar93]

I know I think I'd be more understanding if it wasn't for the versa feeling a bit more accurate 🙄

[SunsetRunner]

I hear you as I can be doing burpees and I am not even in a fat burning zone!!!! But my heart is pounding 😅😅 I feel cheated as this is something a fitness watch should get right!!!! 

[BarefootRunner]

Hi

Exactly, I powered out 4 miles and was dripping and my Sense read my HR as resting HR.  I had the exact same issue with the Sense 1. 

[BarefootRunner]

I have the Charge 4 before purchasing the Sense and it seemed to read OK. Same deal as your Versa.