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Your Fitbit fitness tracker might be lying to you

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Re: Your Fitbit fitness tracker might be lying to you

#21

Post by equalsione »

A really good source of info on this is DC Rainmakers blog. His comments [1] on the lawsuit are worth reading if you're interested.

In terms of heart rate accuracy, HR straps aren't always accurate either depending on placement, body and ambient temperature, moisture etc. Certain heart conditions can cause the strap (or maybe more accurately the software processing the data) to significantly underestimate heart rate too.

[1] http://www.dcrainmaker.com/2016/01/fitbits-multiple-lawsuits...

Re: Your Fitbit fitness tracker might be lying to you

#22

Post by alistairSH »

zimpenfish wrote: post #2

(The HN title has "might be" where the page currently has "is".) > However Teresa Black, along with two other claimants, is arguing that her Fitbit reported a heart-rate of 82 bpm while her personal trainer recorded this at 160 bpm. I find it somewhat hard to believe that you can be this oblivious as to your own heart rate, especially at high levels. [Edit for personal anecdata] Also "approaching the maximum recommen…

[1] Unless the Garmin HRM is having one of its moments where e.g. it claims I'm sustaining 250bpm for 4 hours.

Are you sure you don't have an arrhythmia? My HRM used to do that; turns out I was experiencing supraventricular tachycardia (SVT). I didn't have any symptoms other than my left atrium going bonkers due to a rogue electrical signal in my heart (no lightheadness, no pain, no noticeable loss of athletic performance).

Re: Your Fitbit fitness tracker might be lying to you

#23

Post by alistairSH »

JustSomeNobody wrote: post #10
mirsadm wrote: post #8

Earlier quoted context omitted.

They are mostly accurate. I use a Garmin Forerunner 235 and the average heart rate seems to be mostly accurate. I don't really pay attention to the absolute values though. It's only interesting to see how they change as I my fitness improves.

And this is an important lesson the plaintiff's trainer should have stressed. The actual numbers aren't (quite) as important how quick they rise and fall as you push and rest.

Except a reading of 60-80bpm when the actual is 160-180bpm is completely inaccurate. Those are opposite ends of most people HR range. 60 is close to, or actually, resting for most people. 160 is a hard aerobic effort, bordering on anaerobic, for most people. The FitBit, if the report is accurate, is completely useless as a fitness tracking devices (WRT to heart rate).

Re: Your Fitbit fitness tracker might be lying to you

#24

Post by cptskippy »

lmm wrote: post #7
zimpenfish wrote: post #2

(The HN title has "might be" where the page currently has "is".) > However Teresa Black, along with two other claimants, is arguing that her Fitbit reported a heart-rate of 82 bpm while her personal trainer recorded this at 160 bpm. I find it somewhat hard to believe that you can be this oblivious as to your own heart rate, especially at high levels. [Edit for personal anecdata] Also "approaching the maximum recommen…

> Also "approaching the maximum recommended heart rate for her age [...] may well have exceeded it, thereby jeopardizing her health and safety" seems a bit far-fetched - I'm not a small fellow by any means and I struggle to get my heart rate up to my max (~180bpm), much less over it[1]. Hmm. I'm pretty overweight and can easily go over 180bpm if I'm not watching myself on the treadmill - 5 minutes at 10-11kph will do…

So how aware are you of your heart-rate?

I'm keenly aware of when my heart-rate rises, I notice it jump if I sprint up a stairwell. When it gets too high I can feel the pressure in my neck and temples. I'm the most out of shape I've ever been at this point in my life and I'm alarmed sometimes at how often my heart-rate stays high after seemingly inconsequential physical exertion so I'm wondering if it's something you tune out when you're really out of shape or overweight.

Re: Your Fitbit fitness tracker might be lying to you

#25

Post by zimpenfish »

alistairSH wrote: post #22
zimpenfish wrote: post #2

(The HN title has "might be" where the page currently has "is".) > However Teresa Black, along with two other claimants, is arguing that her Fitbit reported a heart-rate of 82 bpm while her personal trainer recorded this at 160 bpm. I find it somewhat hard to believe that you can be this oblivious as to your own heart rate, especially at high levels. [Edit for personal anecdata] Also "approaching the maximum recommen…

[1] Unless the Garmin HRM is having one of its moments where e.g. it claims I'm sustaining 250bpm for 4 hours. Are you sure you don't have an arrhythmia? My HRM used to do that; turns out I was experiencing supraventricular tachycardia (SVT). I didn't have any symptoms other than my left atrium going bonkers due to a rogue electrical signal in my heart (no lightheadness, no pain, no noticeable loss of athletic perfor…

I guess it's possible but it's fairly rare (hasn't happened for a good long while with the new Garmin strap) and is normally fixed by adjusting or swapping the strap for another.

Re: Your Fitbit fitness tracker might be lying to you

#26

Post by lmm »

cptskippy wrote: post #24
lmm wrote: post #7

Earlier quoted context omitted.

> Also "approaching the maximum recommended heart rate for her age [...] may well have exceeded it, thereby jeopardizing her health and safety" seems a bit far-fetched - I'm not a small fellow by any means and I struggle to get my heart rate up to my max (~180bpm), much less over it[1]. Hmm. I'm pretty overweight and can easily go over 180bpm if I'm not watching myself on the treadmill - 5 minutes at 10-11kph will do…

So how aware are you of your heart-rate? I'm keenly aware of when my heart-rate rises, I notice it jump if I sprint up a stairwell. When it gets too high I can feel the pressure in my neck and temples. I'm the most out of shape I've ever been at this point in my life and I'm alarmed sometimes at how often my heart-rate stays high after seemingly inconsequential physical exertion so I'm wondering if it's something you…

When I'm doing something active I'm conscious of it. When I'm sitting at a desk I'm not at all conscious of it. I assume it's normal at such times, but how wouldI know if not?

Re: Your Fitbit fitness tracker might be lying to you

#27

Post by alistairSH »

zimpenfish wrote: post #25
alistairSH wrote: post #22

Earlier quoted context omitted.

[1] Unless the Garmin HRM is having one of its moments where e.g. it claims I'm sustaining 250bpm for 4 hours. Are you sure you don't have an arrhythmia? My HRM used to do that; turns out I was experiencing supraventricular tachycardia (SVT). I didn't have any symptoms other than my left atrium going bonkers due to a rogue electrical signal in my heart (no lightheadness, no pain, no noticeable loss of athletic perfor…

I guess it's possible but it's fairly rare (hasn't happened for a good long while with the new Garmin strap) and is normally fixed by adjusting or swapping the strap for another.

Def. rare, probably no need to panic. Just throwing it out there, as most of the high (or low) readings go away once you get sweaty, or adjust the strap. If the reading stays that high for hours, it's probably worth stopping to adjust the strap, manually check pulse, etc.

Re: Your Fitbit fitness tracker might be lying to you

#28

Post by theli0nheart »

simi_ wrote: post #12

I had a Charge HR for almost a month, got one for my wife too. I finally returned them this week. They're nice to wear and pleasant to use, but the battery lasts one day and the reported steps/calories/distance is basically science fiction.

You must have had faulty devices. My wife and I both have one as well and the battery lasts about 5-6 days before needing a recharge.

Re: Your Fitbit fitness tracker might be lying to you

#29

Post by other_herbert »

alistairSH wrote: post #23
JustSomeNobody wrote: post #10

Earlier quoted context omitted.

And this is an important lesson the plaintiff's trainer should have stressed. The actual numbers aren't (quite) as important how quick they rise and fall as you push and rest.

Except a reading of 60-80bpm when the actual is 160-180bpm is completely inaccurate. Those are opposite ends of most people HR range. 60 is close to, or actually, resting for most people. 160 is a hard aerobic effort, bordering on anaerobic, for most people. The FitBit, if the report is accurate, is completely useless as a fitness tracking devices (WRT to heart rate).

I've got a wahoo tickr chest strap that will report something like half my real HR from time to time... all of these monitoring devices are intended to give some helpful information to go along with a workout, NOT to be a reliable medical device...

Hopefully there'll be some sanity with how this is handled...

Re: Your Fitbit fitness tracker might be lying to you

#30

Post by timrichard »

pragone wrote: post #14
zimpenfish wrote: post #5

Earlier quoted context omitted.

They can be accurate - In a static test I did the other day, the Charge HR reported the same* as the Garmin HRM, Withings Scales, and a finger pulse oximeter. It was within 5-10bpm of the Garmin on a 25 minute run after I'd adjusted the position according to their advice for exercise. * they were all within 5bpm

Finger pulse ox meters are often inaccurate and can't be trusted to give a reliable pulse for a whole host of reasons

I've been wearing a Pulse Ox for a few days, which uses a Optoelectronics sensor.

I've checked the reading three times by comparing with my radial pulse, counting against my wristwatch. Each time it was bang on, or within 2bpm.

That's when fairly inactive, though. Will have to check it's consistent at much higher pulse rates.

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