
Your Fitbit fitness tracker might be lying to you - ollysmit
http://www.thememo.com/2016/01/08/fitness-trackers-panned-for-wild-inaccuracies-and-putting-lives-at-risk/
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zimpenfish
(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 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]. My highest recent was avg.173bpm, max.184bpm for an illness-
recovery 10km.

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

~~~
lmm
> 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 it.

~~~
cptskippy
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.

~~~
lmm
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?

~~~
cptskippy
I think it's pretty normal to not be conscious of it when it's at a resting
rate. I guess what I meant to say is that I'm conscious of it when it's not at
a resting rate and alarmed when it isn't and I feel like it should be.

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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...](http://www.dcrainmaker.com/2016/01/fitbits-multiple-
lawsuits.html)

~~~
sgdread
My practical experience: optical trackers almost always lie to me when I do
intervals training (though, I haven't tried expensive high-end dual-wavelength
devices), while wet chest strap is pretty accurate. As instructions say: just
put some water on strap and it will work.

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mirsadm
Optical HR monitors aren't that accurate. They are only useful if your
analysing trends over time. People that buy these fitness trackers and expect
medical level accuracy are either misled by deceiving marketing or not doing
enough research.

~~~
zimpenfish
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

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

~~~
timrichard
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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draugadrotten
Nothing to see here. Circulate. The only result out of this will be fatter
lawyers and a 42 page EULA for FitBit which you have to sign before you are
allowed to wear the device. Poor US of A.

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simi_
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.

~~~
theli0nheart
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.

~~~
simi_
I'm inclining towards this option, too. I didn't think it was likely because
both watches (can you call them that?) had the same issues. This reminds me of
my experience with Razer: out of 5 mice bought (4 abyssus, 1 orochi), two were
faulty.

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SilkRoadie
I have always found these things to be a bit iffy. I think it is difficult to
accurate track the number of steps or distance you have travelled.

As for heart rate you would think it is easier but again I guess it would
depend on the fit around the wrist and the position on the wrist to determine
it accurately.

I don't really understand why people are suing over this. If your heart rate
is 160 and your Fitbit is saying it is 80 then you return it for a refund or
replacement. You don't train yourself to death.

It is a bit like if your sat nav says drive a across a field then into a
river.. you should be using your judgement - not deferring it to some device.

If you are struggling to catch your breath or feeling a bit funny then
typically you would ease up rather than run yourself to death on a devices say
so. I would hope that most people are smart enough to determine that if they
can feel their pulse pounding and the monitor says you are barely above
resting heart rate then something is probably incorrect with your device.

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SixSigma
My parents are lying to FitBit. They get rewards from some place as Amazon
gift certs, so my dad has built a step faker using an electric motor. They
have made about $50 from this so far.

~~~
xkcd-sucks
Your dad is more of a hacker than ninety percent of the people in this thread

~~~
SixSigma
He used Meccano too. Which didn't go down too well when he tried to take it
through in his hand luggage on a recent trip to Spain. Was no trouble in the
end but they made him take everything out of his bag and scanned it
individually.

In the 1970s he was a computer mechanic, with a spanner and oil and all that
kind of stuff. There were only two of those computers in the country, one at
Raleigh Cycles and one at Cabdury Chocolate. They used them to do the wages.
They had an agreement that if one broke he or his opposite number could jump
in a car and drive to the other with a box of cards to run the batch and then
fix it later.

He used to take me to work on a Monday night and it's where I got interested
in computers. He stopped working in 1978. I wish I had been old enough to
understand it more. I was 6-8 at the time.

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praseodym
Compared to the iPhone 6's built-in step counter, Fitbit is sometimes off by
as much as 2x. I wouldn't rely on either of them.

~~~
zimpenfish
I'm seeing decent agreement between the Charge HR, the iPhone 6, and the
Garmin 920XT - although this is only my first week of HR ownership.

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shallowpedantic
not might be, is. example, walked from my job to the downtown mall. my note 4
said I only walked 3500 steps, yet somehow my fit bit said I walked somewhere
in the neighborhood of 6000.

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DrScump
Does this imply that they took the wrong technology from Jawbone?

