Fitbit lawsuit: Hmmmm...

segacs

It'll be interesting to see how this plays out:

The makers of the wearable heart rate monitors are facing a lawsuit that claims two Fitbit models (the $150 Charge HR and $250 Surge) do not accurately track heart rates during exercise.

http://www.today.com/health/fitbit-lawsuit-alleges-heart-rate-monitors-are-inaccurate-misleading-t65956

For what it's worth, I haven't tracked my Charge HR against any other heart rate monitor to test it for accuracy. But I can tell that it's not 100% accurate by any means. Then again, I don't really need it to be. It's just a gadget.

d_thomas02

Exactly.

If I really wanted accuracy I'd be wearing a chest strap. I just want an idea of my heart rate... all day long... and in comfort.

Last chest strap I wore {admittedly an old but working hand-me-down} left a rash under the entire strap after one 30 minute workout as if it was covered in poision ivy oil.

NancyN795

I still wear my chest strap for some workouts. The average heart rate number that I get at the end of the workout from the two devices (chest strap and Fitbit) is always within one or two BPM of one another and I haven't seen any big discrepancies in the maximum heart rate, either. The biggest difference that I've noticed is that my Fitbit almost seems to need to "warm up". At the beginning of the workout, my Fitbit heart rate rises more slowly than my chest strap heart rate.

And, I agree that I don't need or expect my Fitbit to be 100% accurate. It is a gadget, but one that I find to be very useful. I doubt that the lawsuit will succeed.

macgurlnet

NancyN795 wrote: »

I still wear my chest strap for some workouts. The average heart rate number that I get at the end of the workout from the two devices (chest strap and Fitbit) is always within one or two BPM of one another and I haven't seen any big discrepancies in the maximum heart rate, either. The biggest difference that I've noticed is that my Fitbit almost seems to need to "warm up". At the beginning of the workout, my Fitbit heart rate rises more slowly than my chest strap heart rate.

And, I agree that I don't need or expect my Fitbit to be 100% accurate. It is a gadget, but one that I find to be very useful. I doubt that the lawsuit will succeed.

I'm no expert in how the cardiovascular system works by any means, so if I'm off the mark here, someone let me know.

But it would be reasonable to see a delay in the wrist-based HR monitor picking up your elevated heart rate - after all, it's further away from your heart than the chest strap one. Similar to how you wouldn't immediately see an increase in the flow of water down a river if it was flooding upstream. Given time, you'd see the increase, but a person at the source would see it right away.

With regard to the article...using a gym machine as your other source? How reliable are those, really? And there's no mention of how much of a discrepancy she saw - 5 bpm? 20 bpm? Was she wearing the Fitbit properly? I've read there's a recommended positioning for optimal detection, especially during exercise, which may be different from how folks wear them usually.

It seems such a petty little thing to me. I doubt it's gonna go very far, other than some publicity.

~Lyssa

abatonfan

macgurlnet wrote: »

NancyN795 wrote: »

I still wear my chest strap for some workouts. The average heart rate number that I get at the end of the workout from the two devices (chest strap and Fitbit) is always within one or two BPM of one another and I haven't seen any big discrepancies in the maximum heart rate, either. The biggest difference that I've noticed is that my Fitbit almost seems to need to "warm up". At the beginning of the workout, my Fitbit heart rate rises more slowly than my chest strap heart rate.

And, I agree that I don't need or expect my Fitbit to be 100% accurate. It is a gadget, but one that I find to be very useful. I doubt that the lawsuit will succeed.

I'm no expert in how the cardiovascular system works by any means, so if I'm off the mark here, someone let me know.

But it would be reasonable to see a delay in the wrist-based HR monitor picking up your elevated heart rate - after all, it's further away from your heart than the chest strap one. Similar to how you wouldn't immediately see an increase in the flow of water down a river if it was flooding upstream. Given time, you'd see the increase, but a person at the source would see it right away.

With regard to the article...using a gym machine as your other source? How reliable are those, really? And there's no mention of how much of a discrepancy she saw - 5 bpm? 20 bpm? Was she wearing the Fitbit properly? I've read there's a recommended positioning for optimal detection, especially during exercise, which may be different from how folks wear them usually.

It seems such a petty little thing to me. I doubt it's gonna go very far, other than some publicity.

~Lyssa

I swear I had a nursing professor discuss this as a side note in a lecture (O_O I'm actually remembering stuff from class!). The pulse should be relatively similar when comparing it across various pulse points in the body simultaneously. A pulse deficit would occur if the person's pulse at a further location (like the wrist) is significantly fewer than a pulse taken closer to the heart (apical pulse), and it would point to signs of cardiac output issues.

macgurlnet

abatonfan wrote: »

macgurlnet wrote: »

NancyN795 wrote: »

I still wear my chest strap for some workouts. The average heart rate number that I get at the end of the workout from the two devices (chest strap and Fitbit) is always within one or two BPM of one another and I haven't seen any big discrepancies in the maximum heart rate, either. The biggest difference that I've noticed is that my Fitbit almost seems to need to "warm up". At the beginning of the workout, my Fitbit heart rate rises more slowly than my chest strap heart rate.

And, I agree that I don't need or expect my Fitbit to be 100% accurate. It is a gadget, but one that I find to be very useful. I doubt that the lawsuit will succeed.

I'm no expert in how the cardiovascular system works by any means, so if I'm off the mark here, someone let me know.

But it would be reasonable to see a delay in the wrist-based HR monitor picking up your elevated heart rate - after all, it's further away from your heart than the chest strap one. Similar to how you wouldn't immediately see an increase in the flow of water down a river if it was flooding upstream. Given time, you'd see the increase, but a person at the source would see it right away.

With regard to the article...using a gym machine as your other source? How reliable are those, really? And there's no mention of how much of a discrepancy she saw - 5 bpm? 20 bpm? Was she wearing the Fitbit properly? I've read there's a recommended positioning for optimal detection, especially during exercise, which may be different from how folks wear them usually.

It seems such a petty little thing to me. I doubt it's gonna go very far, other than some publicity.

~Lyssa

I swear I had a nursing professor discuss this as a side note in a lecture (O_O I'm actually remembering stuff from class!). The pulse should be relatively similar when comparing it across various pulse points in the body simultaneously. A pulse deficit would occur if the person's pulse at a further location (like the wrist) is significantly fewer than a pulse taken closer to the heart (apical pulse), and it would point to signs of cardiac output issues.

And there's the counterpoint I was expecting. Thank you!

So then could just be the Fitbit doesn't detect the change right away for some reason. Or maybe it doesn't show a change until the heart rate has been elevated for a period of time. I wonder what the documentation says...I just have the Flex, so haven't looked into how the HR ones do their thing.

~Lyssa

NancyN795

macgurlnet wrote: »

Or maybe it doesn't show a change until the heart rate has been elevated for a period of time.

That is my guess. It doesn't seem to lag that much vs. the chest strap HRM once it is "warmed up".

macgurlnet wrote: »

I wonder what the documentation says...

Not much, really. I suspect it falls into an "intellectual property" issue where they don't want to publish their exact algorithm. Same with how they come up with the resting heart rate. They don't really say how they do it and Fitbit tells me that my RHR is consistently 5-10 BPM higher than what I measure if I take my blood pressure first thing in the morning.

ki4eld

I have to wear a Holter monitor for certain workouts and my HR is always within 2-3bpm of the Holter. Like everything else, I use it as a guide... I don't take it as gospel.

sarahmichelef

Yeah, I read that article and my basic reaction was "cry me a river".