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Heart Rate Accuracy

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Am a new customer with Fitbit and purchased the Charge 2.  I am a heart patient and have been monitoring my heart rate for years and basing exercise on both heart rate and physical symptoms.  In my younger years I participated in biking, hiking, hunting, and skiing.  Currently my exercise consists of long walks.  I have used the Polar (with chest strap) device for years.  From wearing that, along with my medical history and taking my blood pressure frequently, my current resting heart rate has been between 40-45 for several years.  Now during a fairly aggressive walk my heart rate may get up to the low 90's.  In reading about the Fitbit I was mostly excited about having a daily history or the heart rate and the tracking of sleeping patterns.  I have had the Charge 2 for about 2 weeks and so far am very excited about its features.  However my concern is with the difference that seems to be occurring between the actual heart rate and what the device is picking up. 

 

When observing the throbbing heart (on fitbit) while manually (wrist) comparing to the actual they are not in sync.

At Resting HR (actual) the device seems to be approximately a few beats high.

When actual reaches around 70-80 the fitbit seems to be 20-30 beats high.

The rise in heart rate that the fitbit reported is very quick.  My condition doesn't allow my heart to go faster very quickly......wish it did.  In turn heading back to Resting HR my heart drops very quickly and the fitbit seems ramp down slowly.

I have not worn my polar at the same time the Fitbit is on....thought they might interfere.

 

Anyway I am thinking that I am doing something wrong or have a setup incorrect.  Any suggestions  to a solution would be appreciated.  Thanks in advance.

Andy

 

  

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I just started using the charge 2 and know next to nothing about it.  I do however also see a fluctuating heart rate the is off from what mine actually.  Watching what others say...thanks..

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I've used a fitbit since the first Charge HR. With my Charge 2 I noticed the heart rate monitoring fluctuate quite a bit when I first upgraded, but within a few weeks it seemed to settle in and record accurately. In fact it worked perfectly for most of this year. Lately (last 2 months) I've had a number of issues with heart rate monitoring, syncing, and sleep data. In October my resting heart rate suddenly jumped from normal - low 60's - to an absolutely outrageous reading - high 70's. Disturbing. As of today I haven't seen a RHR reading below 75, since September, while I am almost positive my RHR hasn't fluctuated to such a degree.

To be sure I wasn't having any oncoming heart issues, I bought a Pulse monitor (hospital style) and then monitored my heart rate via 3 separate devices (Fitbit, + Pulse Monitor, + Samsung Health/Note 😎 for a few weeks. I can safely say that the Charge 2 heart rate readings have been wildly inaccurate by comparison, always recording data at least +15 BPM higher than my separate measuring devices. 

For example; sitting comfortably now, both Samsung and Pulse readings are within 1 BPM of each other. Identical to readings when I take my own pulse. But when I check my Charge 2 simultaneously it reads 20 to 30 BPM higher, which makes no sense at all. To be specific: 5 minutes ago I had a heart rate of 65 via Samsung, 64 via Pulse Monitor, 64 taking my own pulse, and a whopping 98 (!!!) on my Charge 2. There's just no way my heart is pumping in the 90's right now. At last glance my Charge 2 is sitting at a constant 93BPM while Samsung is telling me I'm at 62 BPM. I know full well my heart rate is not racing at 90+ bpm... even absent confirmation from Samsung, one can "feel" a heart rate that hits 90+ BPM.

Essentially, I'm beginning to think the Charge 2 has been "broken" after an update, or else some other issue has manifested. I'e done the usual things, restarted, worn it higher, loosened it, tightened it, turned the heart rate from "auto" to "on" ..... none of the "fixes" I've read about here have made a bit of difference.

At least the disparity I noted from additional devices has stopped me from panicking, as my RHR is likely not higher than normal. The Charge 2 is simply not reading heart rates correctly, numerous times throughout the day, and missing data when I sleep. It's bloody frustrating though, as it worked fine up until 2 months ago and for quite a while I believed I could rely on Fitbit data. But now I'm sure it's just... incorrect ... most of the time.

Additionally: my sleep "stages" broke at around the same time my heart rate data started getting funky. Sleep "stages" only works intermittently now, and sometimes it won't record my sleep at all & I have to manually input the time. This is really frustrating, as it would seem my wife's 25.00 knock off from Hong Kong seems to work better than my branded (and expensive!) Fitbit.

If there's a MOD willing to answer these issues, beyond the usual "restart", or "wear the band higher", I'd love to get some advice before I throw this out as junk and spend cash on an Apple or Samsung wearable.

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 I was recently on a treadmill that monitors heart rate and noticed it was vastly different than what my fit bit was saying at the same moment in time. My fit bit 2 recorded almost 3 times the heart rate that the treadmill recorded. I got off the treadmill and got on another one and the same thing happened. Makes me think my Fitbit to is not accurate. Also, it recorded my heart rate at 150 and I could tell I was not nearly that activated. 

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I run cross country and my heart rate went as high as 205 BPM on my Charge 2. I should be on the ground dying since the maximum heart rate I should be able to achieve is 204 BPM based on the standard 220-your age=maximum heart rate, so I can thoroughly conclude that the heart rate sensor isn’t accurate and runs high.

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Interesting that some posts indicates the Fitbit runs high.  My experience is that at resting my Fitbit is pretty accurate, but at intense workouts it is very low.  Last week I was working hard going up a hill, and my Fitbit didn't go above 115, but manually taking my pulse my heart rate was over 160.  This has been consistent for a couple years:  no matter how hard I work out, my Fitbit will rarely go over 120.

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Agree that during exercise, the heart rate can be inaccurate. I think there is a flaw in pure pulse tech. The light may not be bright enough and the sensors are not sensitive enough. Apple watch seems to have caught up and is now quite accurate and respond well during exercise. You will notice the optical light intensity is much higher.

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I found it interesting as well. I purchased a Charge HR several years ago because I was interested in monitoring my hear rate. While resting, and day-to-day activities, it would appear the rate is somewhat accurate. However, I found my fitbit device to be very inaccurate while riding a stationary bike. My heart rate gets really high (around 145 BPM), and you can verify this using the bike's HR monitor. However, each and every time my fitbit shows nothing more than 80 BPM (even after moving the device higher on my wrist). I'm somewhat suspicious of the heart rate "algorithm" used. When jogging, my fitbit will show a higher rate (120-130), but it can't get it right while stationary on the bike? Perhaps it tries to "guess" the rate, by tracking movement as opposed to detecting the actual rate.

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Thank you for that. I know when my heart beat has reached close to peak over 5 minutes because I always get a exertion headache about an hour later. Yesterday I jogged 8km in 55 mins and my fit bit showed avg heartbeat 164 with last four k averaging something over 170. It was scary. Should be impossible, I am almost 43

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I thought my Fitbit was reasonably accurate until a couple of weeks ago. It now goes way too high (showing s HR of 200 bpm on a walk!) or very low (80 bpm when on a spin bike then spiking at 200 again)

i Havnt changed anything like where I wear it on my wrist, so a bit disappointing. 

I know it’s not going to be 100% accurate but something’s gone wrong to start showing these wildly innacutrate readings. 

Think I might try an Apple Watch as that gets better reviews and measuring my stats is both important and interesting for me!

shame a had fitbits for about 5 years and was looking to upgrade to their higher end options. Not sure I’d do that now. Expensive as apple are, I’ve never known anything apple to ‘not work’ 

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I've struggled for accuracy with all wrist worn heart rate monitors. I've
tried Fitbit, Garmin, and Apple, and all seem fine when resting, and all
are inaccurate when I'm exercising.

The problems I have might not apply to the entire population: I have
darker than average skin, and I've read that might impact the readings.
The only consistently accurate heart rate monitors for me have been chest
straps.

I think it is worth trying other watches for accurate heart rate readings,
but don't just assume that the Apple Watch will be any better.
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Thanks for the input!

Sent from my iPhone
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I thought when I bought my Fitbit charge 3 that it would help me monitor my heart rate at all times. I have a heart condition that my heart suddenly switches from normal 65 ish to 130 and if I can control it immediately, then it switches instantaneously back to 65 ish. However sometimes I don't notice it right away and I wanted to be able to look at my Fitbit and see what the heart rate was. Last weekend I was aware my heart was racing but the Fitbit only registered 74 when in fact my pulse meter showed it at 135. That is some discrepancy. I have tried changing where I wear it but I think the algorithm is off. A bit of a waste of money, really. Disappointed.

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I  got a Fitbit - Charge 3 Activity Tracker + Heart Rate early in the pandemic-  being I wasn't working out as much I wanted to at least track my steps. Last week, after some gastric distress, I used it to track my resting heart rate to make sure it wasn't elevated. I wanted to assess if it was pending  heart issues, rather than gastric issues alone. My resting heart rate was in the low 70's, but  after reading these replies- was that heart rate even somewhat accurate ? 

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So, (from my perspective) the fitbit does a good job of monitoring heart rate at rest. It does not perform well when you are active, and I can state that as a fact: I recently had a heart attack and my cardio rehab includes a real-time EKG while I am exercising. The "good" news is that the fitbit (when it is wrong), almost always reads much higher than my EKG heart rate. The bad news is that I feel I can't trust the heart rate of the fitbit during exercise. 

I do sympathize with the engineers at Fitbit -- trying to filter and monitor a wave-form from the LEDs and sensors as the fitbit is moving around on your wrist is hard! Fitbit also never claims that the device is a medical device, nor does the company claim it is very accurate. However, I do think that Fitbit is missing an opportunity to create a competitive advantage by investing in better filtering and better algorithms to solve this limitation. 

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The fitbit monitor may display current heart rate accurately, however it records average over time. Your peak can exceed what you see later.

 I’m-not sure of the time frame maybe 30 average is recorded. I have recorded my peck to 174 using a different device, checking back later Fitbit Charge 4 maximum was 158. As most of us are aware the fitter you are the faster your heart rate drops as you reduce effort. 

 

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