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How accurate is your Fitbit?

Posted at 2:21 PM, Feb 22, 2016
and last updated 2016-02-22 14:21:22-05

Two popular Fitbit fitness trackers are at the center of a new class action lawsuit.

The lawsuit alleges that at high heart rates, the heart monitors on the Fitbit Surge and the Fitbit Charge H-R are inaccurate.

Kate McLellan is one of the three plaintiffs in the lawsuit.

“It was dangerous to rely on those numbers because it wasn't accurate,” said McLellan.

According to the suit, McLellan purchased a “Charge HR” to use when she works out.

She says shortly after purchasing, she noticed it was not consistently delivering accurate heart rate readings, particularly during exercise.

McLellan says she called Fitbit and was directed to reboot her Charge HR, but it continued to deliver inaccurate heart readings.

“They advertise it as being great to track your heart rate when you're exercising, but whatever number they're displaying as your heart rate isn't your heart rate,” she said.

The lawsuit alleges the PurePulse Trackers consistently mis-record heart rates by a very significant margin. It claims that failure did not keep Fitbit from heavily promoting the heart rate monitoring feature and from profiting “handsomely” from it. It claims in doing so, Fitbit defrauded the public and cheated its customers.

"I paid extra for the heart rate monitor because I wanted to stay in a safe range, and that's the extra part that isn't working,” said McLellan.

Fitbit released a statement to Scripps Sister Station 10News saying:

"We do not believe this case has merit. Fitbit stands behind our heart rate technology and strongly disagrees with the statements made in the complaint and plans to vigorously defend the lawsuit. Fitbit is committed to making the best clip and wrist-based activity trackers on the market. Our team has performed and continues to perform internal studies to validate our products’ performance.PurePulse provides better overall heart rate tracking than cardio machines at the gym, as it tracks your heart rate continuously -- even while you’re not at the gym or working out. But it’s also important to note that Fitbit trackers are designed to provide meaningful data to our users to help them reach their health and fitness goals, and are not intended to be scientific or medical devices."

Consumer Reports recently tested fitness trackers, including the Fitbit models in question. Both rated excellent in heart rate monitoring.

An attorney representing the consumers in the case called Fitbit’s argument that the devices are not intended to be scientific or medical devices irrelevant.

The attorney released a statement to 10News saying,

“The fact that the heart rate monitors are not “medical devices” is irrelevant. No one said they were. But Fitbit expressly advertised the heart rate monitors’ ability to accurately record heart rates during exercise, and charged a significant premium for that feature. The heart rate monitors cannot and do not perform as advertised. This is classic consumer fraud—promising (and charging for) one thing and delivering something worth less.And, in fact, accurate heart rate readings are useful in maintaining and improving health, as Fitbit itself touts in its promotional materials. Unsurprisingly, we have heard from many owners who, like Plaintiff Urban, believed what Fitbit said and bought Fitbit’s products precisely because they wanted to monitor their heart rate for health reasons.”

In light of the lawsuit, Consumer Reports conducted additional tests at higher heart rates.

"We compared the results to our highest-rated heart rate monitor. In all of our tests, both Fitbit models were found to be very accurate,” says Patrick Austin with Consumer Reports.

As a result, Consumer Reports continues to recommend both Fitbit models.


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