Incorrect Heart rate measurement - Charge 4

[mstinagray]

Just did a workout with my new Charge 4 and my polar chest strap. I was so hoping the good reviews of the HR functionality of this Fitbit were true, but alas, it still cannot track HR properly. If it were only a little off, I would be okay, but same workout with Charge 4 = 115 bpm/avg and a high of 163 with 214 calories burned. Polar measured 155 bpm/avg, high of 188 and 378 calories burned. I hate wearing all this gear, but guess I still have to. So annoying! And yes, if adjusted the strap.

Moderator edit: Subject for clarity.

[ChrisB1966]

Hi, I got the TICKR Fit as I wanted something that was going to be comfortable and the strap is easy to wash and my smart trainer is Wahoo too. I have had a Polar chest strap HRM in the past and they do seem to make the most accurate HRMs so I think you'd be happy with either. 

The reset improved the readings on my Charge 4, but I'm not really using it as I intended to.

[mstinagray]

I love Polar for accuracy 100%. My husband has the arm band one and has no
complaints. I still think a chest strap is the best re: accuracy, but this
one works for him!

[mpls-gtr]

I had a chest strap back in the day... (like 10 years ago) but I only used it for connecting to a treadmill so I didn't have to have my hands on the sensors.  Tech has come a looooong way since then.  LOL.

The chest straps use a much better sensor for heart rate sensing, based on electrical impulses, which is way better than what the wrist based stuff uses, optical sensors. They have to use light through the skin to measure pulse.

(I'm sure most of you already know this, just including it for anyone who stumbles on this post that doesn't.)

I absolutely agree with you though, mstinagray, that the chest strap is best for accuracy.  Problem for me is ease of use... chest strap, gotta get it wet, try and sling that band around and get it clipped, etc.  Wrist worn, much easier but less accurate as its prone to movement.

Arm worn, doesn't seem to have all the goodies packed Into one nice package like the Charge 4, but it does one thing and seems to do it much better.  I chalk this up to the mfg's being able to use the whole footprint of the device to add multiple optical sensors, e.g. the Polar OH1 has 6 optical sensors for HRM.

So... I'll have to equip another piece of tech when I workout, which means my HR data won't be in Fitbit's app anymore, which then leads to having to check another app for that data and trending.  Sigh...

Fitbit, if you read any of this stuff, I have a request that might help with this, although by doing this it's basically admitting that wrist worn HRM's aren't great.  Make another strap for the Charge 4, Versa, and Sense that allows us to wear it further up on the forearm or upper arm. People could just swap out bands before doing a workout. Hopefully, getting a chance for more accurate monitoring by doing so. I say hopefully, as in, 'Hopefully, its not because of the of the number of sensors, or the curve of the device' that is causing the inaccuracies.

P.S. If you need someone to test this theory, make the band and send me one!  😁

Ok I'm done rambling.  Should have my mind made up by the end of the day on the Wahoo or Polar.

[edmundsj]

I am having the same issue. Just got a Charge 4 as an anniversary present, and took it out for a spin this morning on a walk. Was really excited because I heard these types of measurements can be quite accurate. I took a series of measurements when I was walking (and going up stairs). I held  my finger to my neck and counted the number of pulses for 20 seconds, and then multiplying the result by 3 to get beats per minute. I also took my heart rate manually a few times during the day after the walk as I was sitting or just walking around the office. Also, this was *walking*. My Fitbit wasn't jangling around like crazy, and was worn as recommended, about a finger's width away from the wrist bone (towards the elbow). 

Here is the data:

Fitbit's HR / manual measurement 

Fitbit: 90 / Me: 125
110/160

105/165

103/102

133/132

77/78

77/75

80/81

109/135

105/162

As you can see, the fitbit *can* be pretty accurate, especially at low heart rates (<100bpm), but even occasionally at higher heart rates (see the 133/132 data point). The major issue is for heart rates above ~110bpm, it's off by anywhere from 20 to 60(!!) beats per minute. I am going to try some experiments (wearing the watch more and less tightly, adjusting wrist position) and see if I can get reliable measurements above ~110. As it stands, though, this watch is getting returned. I'm really disappointed. I wasn't expecting this technology to be perfect - 10% off? Sure, that's reasonable. But 50bpm off? For a $150 watch whose *main purpose* is to be an activity tracker and heart rate monitor? That's really not okay.

[mstinagray]

Original poster here -- did you find anything you liked! My C4 still sucks!

I advise the Polar arm strap if you don't want to get a chest one. My husband uses it and it's pretty spot on.

Moderator edit: merged reply

[Charge4C]

Hi Mstinagray,  I swapped out the Charge 4 for the Inspire 2 since that way I was saving money if all I was getting was a step counter, watch, and motivation to move every hour.  Unfortunately the Inspire 2 that I have has the same problem with accurate HR at the higher bpm.  So, no, I didn't find anything that I truly like and can recommend.    It appears that it is a fairly large subpopulation of the Charge 4 and Inspire 2 watches that have this issue.  I know they use multiple factories and I wonder if all of us on this thread happen to get watches from the same factory and if it is a QC issue.  Thanks for asking and if they do make a modification and eliminate this issue with future watches, I'd happily buy a new Charge 4 but not unless it is posted that this problem has been recognized and FIXED by Fitbit/Google.  Good luck everyone.

[RBParker]

I have gone back to my Charge 2 which except for being able to keep a charge for as long as it did when new is accurate for heart rate, steps, calories, exercise, sleep ........  I just can't believe that the Charge 4 issues have not been corrected after more than a year!!!!!! I have not found anything better than my Charge 2 unless I want to wear a bunch of stuff for the day!!!  Can't tell you how frustrated I am.

[AlejandraFitbit]

Hello guys, I hope you are doing fine!

I understand how are you feeling and appreciate all the efforts in trying to fix this heart rate issue. Regarding this problem, occasionally your device may have difficulty getting a strong signal, especially during exercises that cause your arm to move vigorously such as high-intensity interval training or boxing. Try to relax your wrist and stay still for up to 10 seconds. You might also notice a spike or dip in your reading as your device finds your heart rate.

As with all heart-rate tracking technology, accuracy is affected by personal physiology, device location on your arm, and type of movement.

For a more accurate heart-rate reading:

• Wear your Fitbit device on top of your wrist, and make sure the back of the device is in contact with your skin.
• When you’re not exercising, wear your device a finger’s width above your wrist bone.
• During exercise, wear your device a bit tighter and higher for an improved fit. The band should be snug but not constricting (a tight band restricts blood flow, potentially affecting the heart-rate signal). Many exercises such as bike riding or weight lifting cause you to bend your wrist frequently, which could interfere with the heart-rate signal if the watch is lower on your wrist.

Have a good day!

[K2HB]

Seriously? This is the best you can do? Deny the problem again?

Moderator Edit: Formatting

[AlejandraFitbit]

Thanks for getting back, @K2HB.

If you have already tried those tips and you keep having issues, the best way to get help for this problem is to chat with us online or give us a call. Click here to get connected.

Happy stepping!

[RBParker]

Have done that several times.

Sent from my iPhone

[Ralf]

If that would help how come that even my 2nd replacement still has the same issue while my old Charge 2 has no problem detecting proper heart rates?

[mstinagray]

My replacement (due to the watch literally breaking on my wrist) also sucks
for high intensity exercise. I give up!

[RBParker]

EXACTLY!!!!!!!!!!!!  That is my experience also! Again, I can not believe it has been over a year and Fitbit has not resolved this Charge 4 issue!!!

[ChiefH60]

I was getting dropouts down to my resting heartrate when stationary cycling. I found that if I keep my arm at my side rather than on the handlebar with the built in HR monitor in front of me, no more dropouts. I think it has something to do with the blood perfusion in the arm if it isn't held down. 

[Helenmn21]

Me too! 

My hr monitor deviates all the time, even when I’m not exercising. I was sitting in bed this morning and my Fitbit said that my hr was 70.  I could hear my pulse in my ear through my headphones and it was around 50. The device took over a minute to adjust and it did it on 2 stages, coming down to 63 first for a while. All the while I could hear my slow steady pulse. It appears that it’s only reading the data intermittently and then it’s extrapolating from there.
 

The other day I did a Fitbit ‘cheat’ where I banged my hand against my lap to get a few extra steps in (I know). The Fitbit seemed to estimate what my heart rate would be if I was running at that pace and it even tapered my recovery time after. I was just sitting but it manufactured all this fake data rather than reading what was actually happening. 

My max heart rate on a run can apparently vary anywhere between 170 and 203. However rowing, assault bike or ski erg never go above 120 even when I can barely breath and think I’m going to puke. 

I didn’t expect perfect accuracy but the problems above render the device completely useless as a heart rate monitor. I cannot even trust the overnight resting data.

[Ralf]

You should try what i once did for **ahem**s and giggles.

Strap your Fitbit around an orange or apple. Then hold it in your hand and go for a run.

You’ll be surprised how hard an orange’s heart can beat. 🤣

[mstinagray]

I gave up. Got a Garmin Venu since it can attach to my heart rate chest
strap. Bye bye fitbit!

[SunsetRunner]

I have recently been sent a replacement after loads of troubleshooting steps. My old one would read mostly way too low but could vary between 70-200 on a vigorous walk. The new one reads ridiculously high, earlier was reading 200 for a gentle stroll around the block. Not sure I’m going to bother contacting support again. Just seems pointless at this point. Clearly a defective product. 

[Newbie71]

“Redacted” is not helping me.