The heart rate monitors on the Fitbit Charge HR and Fitbit Surge are accurate, says Consumer Reports

The heart rate monitors on the Fitbit Charge HR and Fitbit Surge are accurate, says Consumer Reports
Earlier this year, a class-action lawsuit was filed by owners of the Fitbit Charge HR and Fitbit Surge. The suit claims that the heart rate monitors on the two fitness trackers are flawed and that compared to a user's actual heart rate, the Fitbit devices had readings that were off by "a very significant margin, particularly during exercise." But an impartial observer, namely Consumer Reports, had tested the pair and had found that the heart rate monitor on both units was accurate.

The magazine decided that it would behoove them to repeat the testing. And you want to know what changed? Absolutely nothing. Yet, the plaintiffs in the lawsuit claim that their independent tests revealed inaccuracies on the Fitbit devices. The lead partner for the plaintiff says that a board-certified cardiologist put a number of Fitbit-wearing subjects through a series of exercises and subsequently checked their heart rates. The results allegedly showed that at high (exercise) intensity levels, the Fitbit devices were off by an average of 24.34 beats per minute. In the most extreme case, the difference was 75 bpm.

It shouldn't come as a surprise that Fitbit stands behind the readings produced by its devices. Even so, there is enough legalese in the qualifying statement found on Fitbit's website to drive a truck through. "Like all heart-rate monitoring technologies, accuracy is affected by physiology, location of device, and different movements," the manufacturer posts.

Consumer Reports says that when it retested the Charge HR and Surge, both were off no more than 3 beats per minute compared to the readings taken from the Polar H7. The latter is a chest-worn monitor whose accuracy has been proven in tests. There was one strange exception. When a female tester wore the Fitbit Charge and was engaged in high-intensity exercise, the Polar H7 showed a reading of 150 bpm compared to a reading of 144 bpm on the Charge HR. The test was repeated, and the second time the actual heart rate of 150 bpm showed as 139 bpm on the Fitbit. Since we are talking about a 4% and 7.3% variance respectively, we can't imagine that an intelligent jury would return a verdict in favor of the plaintiffs, especially since the other tests were so accurate.

Alas, we are not lawyers (and we don't play ones on television), so our legal opinion is worth what you are paying for it. More importantly though, Consumer Reports continues to recommend the Fitbit Charge HR and Fitbit Surge, although it promises to watch the trial carefully. And speaking of the trial, we are sure that other fitness tracker and smartwatch manufacturers are watching the outcome very closely.

If you consider yourself a legal beagle, click on the sourcelink to read the actual complaint filed with the court.

source: lchbdocs, ConsumerReports via Engadget



1. Hexa-core

Posts: 2131; Member since: Aug 11, 2015

People of this age are getting nmore and more dishonest. The so-called plaintifs who sue companies with no grounds, but just to make free cash. Just like the other plaintifs who sued Apple (yes they had grounds) for the WI-FI assist scandal, but they demanded 5 Million bucks in damages... FIVE MILLION?!?! An amount if money which they won't even be able to reach in a full year of their spendings in their data plans, even with the WI-FI assist turned on!!! Absolutely creepy!

2. Mxyzptlk unregistered

It's plaintiff. What was the point of shoehorning Apple into the mix?

7. Hexa-core

Posts: 2131; Member since: Aug 11, 2015

Mxy! I dislike Apple because of their cruel business practices, but that doesn't mean that I'll wish the company to die or go bankrupt. $5 Million fine for the WI-FI assist scandal iis harsh. I won't ever support injustice done to people, whether I love or hate them. Maybe the 5 million fine is for all those who are affected by the WI-FI assist scandal, but it isn't accurate, because the court or lawyers do not know all those affected nor can compensiate all of them. Not all those who have been affected have sued Apple. And not all of them even live in the U.S!

6. joevsyou

Posts: 1093; Member since: Feb 28, 2015

well 5 million is a broad term they most likely will settle for for lower amount like always and 5 million is fines and fee's for tons of customers and after everyone gets their cut, the consumer will get like $5 a pop = nothing near what they was charged

3. Odeira

Posts: 300; Member since: Jun 29, 2012

FitBit took a page from Apple when they replied to the complaints, "You're wearing it wrong!"

5. joevsyou

Posts: 1093; Member since: Feb 28, 2015

well in this case, they are right. In the instructions they tell people to move the band 2-3 inch above their wrist and make sure it's tight when exercising

4. joevsyou

Posts: 1093; Member since: Feb 28, 2015

a fitbit is there to give you a idea of what your heart rate, it's not a medical device that is glued to your chest like a doctor would do if you was doing a stress test. If you are moving around it's obviously going bounce around on your wrist. Anyone expecting on the dot results when you jumping around is a idiot

8. Hexa-core

Posts: 2131; Member since: Aug 11, 2015

We understand that FitBit isn't for typical medical use. But if it's caught showing inaccurate info, then there's need of investigation, in order to find out if it's a scam devices, built just to decievd people into buying it. Just like how NVIDIA was investigated and caught in their false advitisement of the 4GB GDDR5 of their GTX970 GPU. When in reality, it was 3.5GB of GDDR5 memory, and another 0.5GB of memory of the much slower DDR2 type, and that caused a compromise in the algorithm-decoding work of the GPU. Hence caused games to stutter and run like crap. But I'm delighted to see FitBit found not guilty and their fitness gadgets working as it should!

9. TBomb

Posts: 1634; Member since: Dec 28, 2012

my Charge HR will occasionally jump up to a crazy number of a minute or two.... but it 99% of the time its as accurate as the HR monitrs on treadmills and the doctors finger monitor thing.

10. Af1rPA

Posts: 712; Member since: Jun 12, 2014

The Charge HR is a great device. Too bad mine died after 6-7 months due to me wearing it in the shower all the time (yes i only have myself to blame.) I hope the next version will be water proof.

11. fistigons

Posts: 368; Member since: Feb 11, 2012

Love the heart rate monitor on my Mi Band Pulse.

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