Fitbit, the San Francisco-headquartered fitness technology firm, is being sued by a group of users who claim the company’s wearable devices provide “wildly inaccurate” heart rate readings.
Fitbit devices track the heart rate of the wearer, as well as calories burned, steps, and also sleep.
But some users are claiming that Fitbit devices “do not and cannot consistently and accurately record wearers’ heart rates during the intense physical activity for which Fitbit expressly markets them”.
Fitbit says it does “not believe the case has merit” and that it stands by its technology. However, the company did add that its products are not intended to be scientific or medical devices.
Fitbit users Kate Mclellan, Teresa Black and David Urban filed their lawsuit against the company in a San Francisco court on Tuesday this week. It can be read in full here.
The claimants argue that the pulse trackers in Fitbit’s devices “do not work, and their heart rate readings are wildly inaccurate”.
Teresa Black, a Fitbit user from Colorado, said her Fitbit device once recorded her heart rate at 82 bpm (beats per minute), while her personal trainer manually recorded it at 160 bpm.
“Plaintiff Black was approaching the 25 maximum recommended heart rate for her age, and if she had continued to rely on her inaccurate 26 PurePulse Tracker, she may well have exceeded it, thereby jeopardising her health and safety,” the filing reads.
The margins of error are significant enough to make the trackers “worthless”, the claimants argue.
“The defect … presents a safety hazard because Class members’ could jeopardise their health by relying on the inaccurate heart rate readings and potentially achieving dangerous heart rates,” the filing states.
In the lawsuit, Fitbit is also accused of defrauding the public and cheating its customers.
The company denies the allegations and intends to “vigorously defend the lawsuit”.
In a statement published by ITV News, Fitbit said:
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.”
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