Heart rate inaccurate on Fitbit Sense

[Cameronoates]

Hey 

is anyone else experiencing huge heart rate inaccuracy during exercise with the sense? 

During exercise with the sense it won’t ever get above 120bpm for me 

but if I use my charge 4 during the EXACT same exercise my heart rate is between 145-170bpm in the cardio zone 

It’s extremely disappointing and I don’t want to have to switch to my charge 4 everytime I exercise to ensure accurate heart rate 

defeats the purpose of having the sense 

seriously one of the most frustrating experiences I have ever had.

Moderator Edit: Clarified subject

[Frammus]

it’s hard to not agree with your premise that they shouldn’t be in the business of heart rate tracking

[Irish57]

We’ll stated!!!

[SunsetRunner]

@Frammus , I totally agree if we are talking about Sense or Versa 2*, the only Fitbit devices I owned.

But "older" Fitbit users have said many good things about previous Fitbit devices concerning heart rate tracking. And Fitbit used to be respected for that and it was a reference for their high standards on that, as far as I 've read in various external reviews. And "older" Fitbit users seem not to be used to this, if I understood correctly many of their posts.

So apparently something changed for the worse since last year, at least. Why?

--

* Versa 3 seems to be equally bad on heart rate tracking, I read.

[MarkMM]

The Versa 3 and Sense came out last Septermber with new pure pulse 2 technology which Fitbit claimed would be more accurate. Complaints started in October. I have a versa 3 sitting turned off as I can't even hit 90 BPM walking hard. Don't know how accurate the versa 1 is, but I at least get results. 

[Frammus]

I haven’t got accurate HR results with any of the prior Fitbits other than the first version of the fitbit charge. This is something that is systemic in their platform architecture.

[Tgisele]

I wore Ionic for several years and it was always close! I compared it with several different things and it was in the ball park. Not so with the Sense. 

[SleepyxEquus]

Same! My Ionic always matched my polar heart rate chest strap. Never had issues with anything, now since their updates, it has issues keeping GPS and the heart rate keeps going in and out on my walks. It’s like they wanted all the old versions to be 💩..so we would all blindly just fall in line with the new bands. 

[SonicMojo]

It's a classic bait and switch and almost every company does it now. They can't actually make something that's good and works correctly - because if we ever got hold of that - we would never be back to buy anything else.

But this heart rate detection piece should have been sorted after 10 solid years and tons of products. If something works - it works and there should never need to be any modifications or alterations. However - in Fitbits case - it seems that they are always content with "good enough" and are trying to market themselves as being a competitor to Apple Watch and others by saying they have the latest tech (and charging for it - especially in my case) while quietly hoping that no one really takes the time to notice that some parts of their devices are barely OK.

Joe Average is not going to care whether his heartrate is up, down or sideways - especially if a healthy lifestyle is not his thing - he will simply look at the numbers flashing by and be happy he is still alive.

But for those of us who purchased a specific Fitbit to accompany our workouts or training or whatever it is we are trying to gather intel on - this company should do better - a lot better. It's not as if there are not enough use cases out there.

Sonic.

[Tgisele]

@SonicMojo Exactly. I monitor my HR during all exercises. I (used to)  compare HR and calorie burn so I would know what classes/types of exercise work best for me. I also compare what instructors give me the best workout, it is difficult to do  when I am pushing through the entire class or workout and most of my HR is in fat burning or below the zone. SInce getting the Sense 2+ weeks ago, I have had 2 minutes in peak and very little in cardio. 

[Irish57]

So many excuses on their part and not acknowledging the impact and total picture from calories, heart rate, zone minutes and so on!

[SunsetRunner]

Great post, @SonicMojo .

In my case I bought my first Fitbit last year and Sense in December because I started having some heart problems involving heart rate. So I was very attentive to my Fitbit watch heart rate values. But my lack of experience with HR trackers and my confidence on Fitbit products quality made me take maybe a couple of weeks until I seriously suspected that the Fitbit HR values were really wrong, not my heart. Fortunately, Fitbit HR values were so wrong sometimes that it was easy then to spot where the error was.

For people with heart conditions, this can be dangerous. I came to the conclusion that health authorities should be harder on companies marketing heart rate products, like Fitbit. Just saying their products are not intended for medical use is far from enough, I think.

EDITED LATER:

It is clear that they are also not accurate enough for many users who take their health and fitness seriously.

[Irish57]

Very scary, I exercise to promote cardio health but it’s so inaccurate I’m not sure what to tell the doctor!

[Tdif]

I know that is the problem we spend all this money on these watches to help
us get healthy yet they are not accurate and send ppl in a tail spin
honestly I am going to look into sending this back --
Teresa Di Fonzo

[SunsetRunner]

@Irish57 , since I found out about Sense heart inaccuracies, I chose not to take them seriously, sometimes mentioning some values with a "maybe". But never "dared" to take any Sense heart rate graph 😂 What's the point? And my doctor agreed.

What I've used a lot with my doctor have been the ECG graphs. Really useful and accurate enough as a first approach for medical purposes, according to the doctor. But this is, I think, Sense only feature approved by many countries health authorities. Because they had to.

[SonicMojo]

@SunsetRunner 

I fully expect that Fitbit tries to get the bare minimums for country feature approval and constantly points to the "medical warning" as a way to both justify that they are not at fault if you suddenly push yourself too hard at the gym (and have a heart issue) or expect medical grade accuracy when it comes to their heart rate monitor. 

They walk that fine line to maintain (boost) sales and get something into users hands hoping all the while you don't get too vested in what the tools are telling you before you realize it's not really accurate AND you can't return it.

I am not looking for medical grade accurate for this thing - I would be just as happy if it were "out" by 5 here and there BUT could be good enough to at least keep up with me - which it is not asking too much.

Cheers

Sonic.

[Frammus]

It’s really hard to justify owning a premium device like the sense if it cannot do accurate HR. I’ve always liked the Fitbit app versus the convoluted Health IOS app but what’s the point if it can’t detect HR with any degree of accuracy?

[SunsetRunner]

@SonicMojo , if the Sense heart rate maximum error was +/-5, or even 5%, I would be happy too. That would be enough for my needs, even with a heart condition. And that was about what I was expecting, very naively. 5% would be a maximum error that could be classified as Good. Even as a RMS (root mean square) error. But that's quite far from what we get from Sense many times.

[SleepyxEquus]

Same here. I sent my charge 5 back today and am back to my Apple Watch. Going to try and get my Fitbit Ionic working again. 

[Plw2010]

I recently switched from an Ionic to a Sense Fitbit. The calories burned and HR during exercise is not accurate at all. And that’s comparing it to another Fitbit smart watch. I’m ready to pitch this watch!

Moderator edit: subject for clarity

[jeboone]

I just upgraded from Charge 3 to Charge 5.  It looks like they are using the same heart rate algorithm that give a lag.  I suspect it is some kind of rolling average.  During a workout on an elliptical, my heart rate on the machine reaches a steady level after a few minutes.  The Charge 3 lags the real number with an error of as much as 15bpm.  By the end of a 20 workout the Charge 5 reaches the same reading as the Elliptical reading.  This is not acceptable for my use.