Sense heart rate accuracy should I buy

[Sagishwarrz]

Hi

I see many complaints about the HR accuracy and other sensor. My question is, should I buy it or not? I am getting second thoughts about this product...

Thanks 

[Rach77]

I have noticed that the heart rate readings are quite low when doing intense exercise (e.g spin). My heart rate is usually around 150-180bpm but the sense shows between 130-160bpm. This is most definitely a software issue whereby the algorithm used to detect abnormal heart rate spikes has been capped so that the watch doesn't keep alerting the user to unusual heart rate readings. Fitbit need to address this very soon as it's putting off avid fitness customers which lets face it, those are the main target ordinance for this watch. I'm not jumping ship just yet as there's an update coming soon to activate the ecg feature and maybe this will have made fitbit look at the heart rate algorithm. Here's hoping.

[techcop]

If it's important to you, I wouldn't purchase the sense. The HR is not stable nor accurate.  During exercise it's too low and when you're not exercising it's too high. For example, in the mornings I take my blood pressure readings which includes my pulse. The Sense is always higher than the BP unit which is interesting because there is no movement, just sitting still. So, that's been a big disappoint and not being able to customize the exercise choices. I'm still deciding whether to throw in the towel with this Sense and maybe try the Versa 3.

[MayurP]

Same issue take a look at my post https://community.fitbit.com/t5/Sense/Heart-Rate-accuracy/td-p/4516856 and vote for it if possible

[MayurP]

Same issue take a look at my post https://community.fitbit.com/t5/Sense/Heart-Rate-accuracy/td-p/4516856 and vote for it if possible. i have posted detailed description and posted a screenshot for walk vs intense elliptical session and heartrate comparison between them doesn't make sense. my walking heart rate was comparatively higher than my elliptical and surprisingly showing more calories burned than my elliptical workout

[RickyBobby0205]

DO NOT BUY A FITBIT. In addition to the sensor not being accurate, the sensor will fail in 1 1/2-2 years, like all THREE of mine did. Each time, they tell me to do the same fixes, nothing works then they offer me 20% on the newest model, which always seems to conveniently have just come out a few months before. Support is abysmal at best, they're like a bunch of robots who spew the same script. I will never buy another fitbit product again. Hopefully an IWatch or Garmin will be more dependable

[SunsetRunner]

Hi @Sagishwarrz - I appreciate your concern regarding the Fitbit technology regarding heart rate. Two things to keep in mind when judging. 

• The forums tend to hold questions and comments from people having issues. They do not necessarily reflect the opinions of the majority of users. 
• The Fitbit Sense is not a registered medical device so you will see differences. Personally, I use the Sense info as a general guideline, providing clues as to when I should probably address specific questions to my cardiologist. In this capacity, I am happy with my experience so far with my Sense. 

You can read more about how the Sense tracks heart rate here. My answer to your question of whether or not to buy the Sense is this - If you have serious cardiac issues, talk to your doctor about a medical tracking device. If your concerns are general (like mine) the Sense can be a good tool. 

On a side note, if your concern is A-Fib, Fitbit received FDA clearance for its soon-to-be released app to identify AFib. You can read about it here. 

[t.parker · Accepted solution]

@Sagishwarrz you are not saying what do you need accurate HR for. The wristwatches may not be accurate in certain circumstances. There are many factors that can affect accuracy. I'm not going to get into the topic of whether Sense is more or less accurate because I have no idea. What I know however that Sense will be probably ok for casual use while, none of the use for somebody who uses HR for training (and to be honest, in my case I haven't found a watch yet which does wrist HR reading accurately for my activities). If you think of measuring HR during steady-state activities and you care mostly about calories burned then probably it will do just fine (as long as average HR will get close to reality as the correlation between HR and calories burnt is linear in most of the equations). However, if you base your training on HR, then Fitbit, in general, is rather a poor choice as it gives you a very simplified picture of your HR zones (just three which don't really help with training at all). If you want to base such elements like rest periods on your HR (I do that, for example in bouldering, between each climb I observe HR until it drops to recovery zone before I go for another climb) you need a lot more reliable device to track your HR. Wrist HR will be accurate sometimes and sometimes not because this technology is far from being perfect. Before you decide what to buy, just think about what you need it for and what level of inaccuracy are you able to tolerate. Watch/read reviews and tests/comparisons and decide. It isn't a simple process and nobody here will decide for you because nobody is you (except you :D) 🙂

[Sagishwarrz]

Thank you and for all for the answers.

Regardless of my needs, from my point of view, my expectation from all the things I buy is them to work as expected no matter what I do, of course, there are corner cases but as everyone said here doing running, rest or any other basic sport isn't a corner case.

The thing that I wasn't aware of is about the technology because my wife has Garmin 6s and the HR work perfect no matter what.

Regarding my use, its basic use gym, rest, and play and use the other sensors for my health... 40 is a risky age 

[NeilFinny]

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@techcop wrote:

If it's important to you, I wouldn't purchase the sense. The HR is not stable nor accurate.  During exercise it's too low and when you're not exercising it's too high. For example, in the mornings I take my blood pressure readings which includes my pulse. The Sense is always higher than the BP unit which is interesting because there is no movement, just sitting still. So, that's been a big disappoint and not being able to customize the exercise choices. I'm still deciding whether to throw in the towel with this Sense and maybe try the Versa 3.

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I have found that as well, but not with a blood pressure machine but with Fitbit charge 2 and ionic.

im wearing charge 2 and sense at this moment whilst sitting down 

sense is: 73

charge is: 65

[NeilFinny]

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@Sagishwarrz wrote:

Thank you and for all for the answers.

Regardless of my needs, from my point of view, my expectation from all the things I buy is them to work as expected no matter what I do, of course, there are corner cases but as everyone said here doing running, rest or any other basic sport isn't a corner case.

The thing that I wasn't aware of is about the technology because my wife has Garmin 6s and the HR work perfect no matter what.

Regarding my use, its basic use gym, rest, and play and use the other sensors for my health... 40 is a risky age 

---

40 risky, bah, still a kid 😛

[t.parker]

@Sagishwarrz welcome to the club of 40s 🙂 I don't feel it very risky but probably I should be while being involved in so-called "extreme sports" ;).  To be honest, I don't remember when I felt better than now. When it comes to serious health issues I wouldn't expect a toy watch (yet expensive) to give me any indications of that. Let's face it. Wearable technology isn't there yet and it doesn't matter whether FDA or any other country's similar government body approves a feature. It's just not there yet. Any issues (and in the majority of cases you won't need a watch to tell you there's something wrong) - seek help from a medical professional. I do an annual full checkup so I can sleep better.

Personally, I do not use optical wrist HR for any tracked sport. When I had Fitbit devices, they were always off, and very often Charge 2 couldn't even register any HR. Ionic's HR was all over the place. I believe, resting HR was more accurate. With Suunto SSWHRBaro - oh my, I have never ever seen worse wrist HR readings - EVER! Well, at least I saved battery by turning off the sensor (although, in Suunto's defence, the Spartan line was the first one with HR sensor and manual clearly said they didn't trust this tech either and recommended using external sensors :D). Garmin Fenix 6 Pro - works and doesn't - for me, hit and miss. Depends really on the sport. Good for running, even cycling is pretty much spot on but rock climbing - not that much. The point is, the accuracy of wrist-based HR may change instantly just by changing some conditions. Yes, Sense may be worse than some other watches (according to reviews and, to be honest, my experience with Fitbit devices doesn't make me thinking positive either)  but when I really want to rely on HR, I use a chest strap or in some cases optical PolarOH1 (which is really great, spot on with chest strap 99% of times but has a small lag in readings). Why not Fitbit? The answer is simple - the devices still don't support connecting external sensors and data output is very poor. Suunto and Garmin do support it and when I use the Polar chest-strap both watches can connect to this one strap (I love the dual BT feature in this strap!). That's why your needs are the most important here. You should get your gear to meet your needs rather than adjust your needs for the gear. It doesn't matter whether you go for Fitbit, Polar, Garmin, Suunto. Find something that works for you. If you are worried about the quality of HR and still thinking of Sense then buy it and you have 45 days to return if you are unhappy. You may use Amazon, returns with them are simple. There are plenty of options and it's lots of money to spend so I wouldn't rush 🙂

[FloppyDrive]

When I compare my Sense with Kardia Mobile, I get the same resting HR. Home blood pressure monitors are notoriously inaccurate. There appears to be some algorithm smoothing going on, so that may be the reason you don't see high peak readings during exercise. Should two beats be used to determine heart rate?

[NeilFinny]

OKAY

I purchased a Polar OH1 the other day, linked below is a comparison run of the results.

Now I have tried to match up, but a few issues.

1. Fitbit is usually tracking every 5 seconds, sometimes it has longer and lesser gaps. Polar is tracking every second. So I have had to dump some Polar date, and I've just matched time for time.

2. Polar early on had some drop outs, I think it was cause I pressed the button cause it was the first time I touched it and didn't know if it was the right way to switch on.

The findings isn't too bad for fitbit, but there is some points it is out.

https://www.studyhost.net/fitbit/fitbit.html

[Zwyvel]

Same here.  I had a Charge 2 for years and my resting HR was mostly between 59 and 62. Since I use the Sense I'm between 68 en 70.  When running my average on the Charge 2 was around 135. On the Sense 158.  What I would love to know is which is most accurate.

[TecTopcat]

I have the exact same issue, with the Sense as tested against a Charge 2, BP device, Kardia and Polar, the Sense is off-wouldn't be so bad if it was consistently off by say 10 beats but it is more like 15 when at rest, and then varies wildly other times. Any resolution?

[qmeg23]

I feel the same way as you RickyBobby. DO NOT BUY A FITBIT. I started out (about 6 years ago) with a flex. I am now wearing a fitbit charge and find it reasonable but the face is cracked. I purchased a Versa (my fourth fitbit) and found it to be totally unreliable. It looks nice and thats all. I feel like taking it outside and smashing it to bits. I wear it mainly for heart rate and sleep but I refuse to pay extra for sleep stats. Versa doesn't sync properly and since I did an update it doesn't sync at all.

[radzieus]

The Sense is completely inaccurate past 140-150bpm. It jumps down to 90, up to 126, usually sits at 110. I wear a chest strap at the same time and my HR during this time is usually about 170-180. Completely. Inaccurate. 
The Fitbit Versa Lite, however, was always spot on with my chest strap. I wish I had stayed with that version, it was much better, even thought it is an older model. This will probably be my last Fitbit. Junk. 

[SunsetRunner]

I use a high quality chest strap, it will read 132 bpm during a cycle workout while my Fitbit Sense reads 108.  You tell me, does that seem like a small problem, and why won’t Fitbit allow you to connect to external chest straps.  Their top competitors do.

[SunsetRunner]

You are correct on acceptable expectations, but there are better heart rate options, say a chest strap.  Apple pairs with them, why doesn’t Fitbit?