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Fitness Trackers Out of Step When Measuring Calories, Research Shows (theguardian.com)
Fitness devices can help monitor heart rate but are unreliable at keeping tabs on calories burned, research has revealed. From a report on The Guardian: Scientists put seven consumer devices through their paces, comparing their data with gold-standard laboratory measurements. "We were pleasantly surprised at how well the heart rate did -- under many circumstances for most of the devices, they actually did really quite well," said Euan Ashley, professor of cardiovascular medicine at Stanford University and co-author of the research. "At the same time we were unpleasantly surprised at how poor the calorie estimates were for the devices -- they were really all over the map." The team tested seven wrist-worn wearable devices -- the Apple Watch, Basis Peak, Fitbit Surge, Microsoft Band, Mio Alpha 2, PulseOn, and Samsung Gear S2 -- with 31 women and 29 men each wearing multiple devices at a time while using treadmills to walk or run, cycling on exercise bikes or simply sitting.
This is probably true of any fitness device that claims to track calories. The new shiny shiny is no exception.
A Pirate and a Puritan look the same on a balance sheet.
Big boned people like me burn calories differently. So that explains it.
a really fucking stupid summary by a retard, imho
That's all I need to know.
From the blurb, "...errors on energy expenditure... ...ranging from the lowest at 27.4% for the FitBit Surge to the highest error of 92.6% for the PulseOn device."
There are too many variables involved in determining calories burned by any biological entity, and these 'fitness bands' are not the only device that has this problem, either. The closest you can come are devices that measure power generated by your muscles (PowerTap hubs, SRM or Quarq cranksets and other bicycle-mounted direct measuring instrumentation like them, rowing machines with an ergometer, etc), and even then there is a variable 'biological efficiency' term in the equation that means you can only call it an estimate. Some of the worst accuracy devices are things like the treadmills and stationary bikes in a public gym, which just use statistical averages of a range for calories burned given a level of exertion, and even then they tend towards the high end of the range to keep people motivated to continue using the treadmill or stationary bike. Something like these fitness bands work in a similar way, and I'd fully expect that they too tend to estimate on the high end of the range of 'calories burned' to keep you motivated. The fact that they track heart rate means it's a little more accurate, given one more term in the equation, and if they have a way to enter your bodyfat percentage, that would improve the estimation also. There are other factors you can plug into such an equation to make it more accurate, but in the end it's still just an estimate because of the efficiency factor. Therefore: none of what is being claimed here about it's lack of accuracy in 'calories burned' is terribly surprising. Of course for the average person, moving their body for significant amounts of time (not just getting off the couch, going to the 'fridge for another soda/beer, then back to the couch) is good regardless of trying to track 'calories burned', and to be quite honest, your dietary intake is more important when trying to lose excess bodyfat than exercise is. Of course you don't need any 'fitness bands' for that, just a decent pair of running shoes, so that doesn't make the company any money now does it?
So strapping an accelerateometer to your wrist isn't an accurate way to measure calories, even with all that big-data, cloud computing, web 2.4 social media magic algorithms?
Next you'll be telling me this $500 web connected juice press was a waste of money, and that someone can hack my IoT light-bulbs!!!!!
How on earth could they not include any one of the Garmin devices? I guess they had costs involved but still seems like they'd include one of the (I assume) most popular fitness trackers available.
Give a hand, not a hand-out.
Shiny makes feel good!
Pretend to self shiny is for health, not to be toy!
-- Tigger warning: This post may contain tiggers! --
There are too many variables involved in determining calories burned by any biological entity, and these 'fitness bands' are not the only device that has this problem, either...
To further put this into context, if your body takes in 2 calories more per day than is needed, you will be obese in a year.
No diet has that level of accuracy, and there are variations within different samples of food as well. That 10oz of chicken might vary by dozens of calories, depending on random circumstance.
Laboratory animals grown with the same caloric intake and same access to exercise are obese, compared to ones grown decades ago. The trend over time is consistent and compelling. We're also seeing obese 6-month old babies.
The current explanation is that you consume more than you need, but the body knows how much to extract and lets the rest go by. The body has a "weight setpoint" in the manner of a thermostat that tells it how much energy it needs, and something in the environment causes that setpoint to go slightly off, causing obesity. Over 900 environmental causes have been identified as potential causes of obesity (and researchers are working through the list).
Obesity has, apparently, nothing to do with the amount or type of food you eat(*), and neither the amount of exercise you do(*).
(*) For obesity. Whether eating junk food is any good for you is another matter.
(*) For obesity. Whether exercise is good for your health generally is another matter.
The accuracy of these non-clinical wearable health monitoring devices are just awful. They would never pass an FDA 510K clinical trial. Drop the phrase "FDA 510K" at any of these wearable health and fitness manufacturers and they just shut up and go away.
The bigger issue here is that most of the devices tested were gen 1 devices and I think that the technology and software has gotten better.
Basis Peak is not even on the market anymore.
The rest have been surpassed by multiple generations.
http://www.mdpi.com/2075-4426/...
or at least very obsolete, given that the official SI unit for food energy is the Joule.
If you say a certain one-hour exercise burns, say, 600 kcal, is that in addition to the expenditure by the resting metabolism, or including it? I've tried to parse this from the instructions of different monitors, but so far utterly failed to find anything.
According to the study, the Apple Watch was the best of the bunch with a median error of 2%. That's pretty damn decent if you ask me.
Why don't you just multiply the number you see by 4184 and leave the rest of us the hell alone.
I've yet to see Joules listed on nutritional labels, and I live in a metric country.
The only thing defect would be to give people units they don't understand to compare to units that aren't listed anywhere to appease idiots who insist on SI for SI sake.
People should use common units. Not SI units, but COMMON units. You hear that you weirdos with your miles?
Yup, your anectdote completely invalidates other people's anectdotes. And, clearly, your illness makes you a perfectly representative sample of the population.
Like over 90% of the earths population I, too, live in a country that signed the SI treaty - and the "nutritional information" printed on food here is obliged to present the food energy in Joule. (Many still also print "calorie" values in addition, but that is optional.)
The most bizarre thing about "calories" is that most people who talk about them use numbers that are off by a factor of 1000 - just as if people were talking about "bytes" while in fact they mean kilobytes.
The most bizarre thing about "calories" is that most people who talk about them use numbers that are off by a factor of 1000 - just as if people were talking about "bytes" while in fact they mean kilobytes.
Oh true that. It's like the k in kcal on the label is meaningless. Food labels get this right, but what really annoys me is references like Google's search results could correct for this. Googling "Calories in an Apple" gets you "52 calories" per 100g. Not 52kcal not 52000cal but 52cal.
What chance have people got if their reference material is wrong. "You're saying it wrong"... "nuh uah Google it".