Fitbit heart rate monitoring is accurate says Consumer Reports

US magazine claims Charge HR and Surge heart rate tracking is just fine
Fitbit is accurate says Consumer Reports

Consumer Reports is backing Fitbit by claiming the company's heart rate monitoring on the Charge HR and the Fitbit Surge is accurate.

The American consumer rights-focused magazine decided to carry out further tests in response to the lawsuit filed against Fitbit, which claimed that heart rate monitoring was inaccurate, particularly for high intensity levels. The lawsuit claimed that readings were off on average of 24.34bpm (beats per minute) and could be as much as 75bpm off an accurate heart rate reading having carried out tests with a "board-certified cardiologist."

Read this: Best heart rate monitor and HRM watches

Those new tests involved getting a male and female volunteer to perform a series of treadmill runs, each with a Charge HR and a Surge. The two trackers were tested against the Polar H7 heart rate monitor.

The Polar chest strap monitors heart rate using ECG technology, which involves measuring the heart's electrical activity and is regarded as one of the most reliable ways to record heart rate data. Unlike the H7, Fitbit's fitness trackers use proprietary PurePulse optical heart rate sensor that flashes lights against the skin to detect changes in blood volume to produce a bpm reading.

After its initial tests with the Charge HR and Surge focused on resting heart rate and monitoring under moderate exercise, the new round of tests examined heart rates at rest, a walking pace (110bpm), jogging pace (130bpm) and running pace (150bpm).

All of the tests were conducted twice with a total of 64 heart rate measurements recorded. Those tests showed accurate readings against the H7, with variances in data no more than 3 heartbeats per minute.

It wasn't all plain sailing though. When the female tester used the Charge HR for a higher intensity run, the chest strap gave a reading 150bpm while the Fitbit Charge HR read 144bpm. For the second run, the tracker produced a 139bpm reading. Consumer Reports said that the inaccuracy disappeared when the Charge HR was worn on her forearm. The Surge meanwhile, apparently had no accuracy issues whether it was worn on the wrist or the forearm.

So do these tests definitively prove that there's nothing wrong with the heart rate monitoring on the Charge HR and the Surge? Well, not quite. It's still a limited way of investigating the issue and if you've read our recently updated Fitbit reviews, we remain unconvinced that they are good enough. Also, who wears a Fitbit on their forearm?

We'll be carrying out our own in depth testing of wrist-based heart rate monitoring including the Charge HR and Surge in the very near future to wade in on the big Fitbit heart rate debate.

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  • Mikoww says:

    Although I liked Fitbit dashboards and apps (but dislike their closure to HealhKit), I left my Fitbit charge HR few month ago because while exercising, the heart rate datas were not only inaccurate, but also there were a lot of "heart rate losses" during activities (no more indications about HR).

    You just have to visit the Fitbit Forums to notice how many people reported the same issues...

  • slavi90 says:

    Waiting to see your tests. Glad to have you and from your opinion will depend which tracker to take!

  • AndyB says:

    Consumer Reports suggesting that the FitBit heart rate is this accurate has me doubting Consumer Reports. I've had a the Charge HR for over a year, and have had it replaced in that time, so I have personal experience with 2 units. My daughter has the Charge HR as well. Running, and even brisk walking, will often throw off the heart rate my 50+ beats. I have spoken with others and no one I've spoken with has as good an experience as Consumer Reports is suggesting.

    My daughter and I have experimented with the device and for accurate reading during running, it helps to wear it as high up as possible. I loosen the strap as much as possible and push the unit up onto the muscular part of the forearm, and then tighten it there. Even with that, reducing jostling of the device is required for accuracy. To do this, I've resorted to holding my arm almost straight ahead of me, which looks ridiculous, but without this, the heart rate may register as 100-130 when it should be closer to 150. 

    When the rate is way lower than it should be, if I stop and keep my arm still,the number displayed rises after a few seconds of standing still, but of course during that time, my heart rate is dropping rapidly and I don't get credit for cardio or peak zone. (I like getting the credit for the hard work and pain that I endure)

  • Steelcitydubber says:

    theres no way it's accurate. I was panting and sweating on my first bike ride of 2016 today, a  quick old-fashioned check of the pulse at the top of the hill and it was at least 120bpm, my surge HR was saying 75 bpm! This after 30 minutes mountain biking, I'm a 95kg unfit 38 year old.

     Strap was tight enough to stop it slipping on my wrist. not impressed. May try it on the inside of my wrist instead but I'm not convinced.

    Plus it says I've done 10,000 steps when I've done nothing but drive all day.

  • MickeyD says:

    I've had my Fitbit Charge HR for almost 3 months now and while I'm not an athlete I do get in some good exercise on a daily basis and I find the HR to be fairly accurate.  I always wear my Fitbit a little taught because if it slips down on my wrist I can't imagine that it would provide an accurate reading.  During the day my average rate is in the low to mid 70's and while walking it hit's 105 - 115 depending on the grade - level or uphill.  During jogging I usually hit around 130 or more and when I burst into a sprint I get up above 150 - I'm 63.  I've done the old fashion radial pulse and carotid check enough to know that the HR is pretty close and the only real way to tell would be to have a doctor hook up EKG wiring, put you on a treadmill with your HR and compare the two.  At any rate, while I was a disbeliever at first, I think the HR works just fine.

  • Petra says:

    I have a graduate science degree with over 30 years of scientific research. Just recently my children gave me a Fitbit Charge HR watch. Although I heard about the problems some of the users seem to have with it, I asked for it to evaluate it and see for myself. I tried it under various conditions and to my amazement I found NO Technical problems with the unit providing one uses it properly and understands the basic principle on which it was designed. I followed exactly Fitbit's instructions and found no problem with the readings under the various setting which I used it under. Actually it responded to the physical condition I was in. For instance, using both wrists including the forearms and a resting position and going up and down the stairs, etc.Although I did not notice any discrepancies in the readings under the various settings, it only makes sense to meif it is worn, a) snugishly, b) on either of the two wrists although the left is preferable, because of it s closeness to the heart, and, c) wearing it at the forearm if possible. The invention is amazing. Let us not throw the baby with its bathwater!!!

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