Can someone figure this math out for me? I'm stumped.

questionfear
questionfear Posts: 527 Member
in Fitness and Exercise
So in my spare time I do reviews for a tech website, and a fairly well known athletic company asked me to review their second string fitness tracker (I'm not using names because I don't want to accidentally slam them before I'm sure).

I noticed their device had me burning 3,000 calories on an average day (I walked around 6k steps and did a 1/2 hr of a bodyweight workout, which I logged with the device). Since this seemed extraordinarily high, I asked them to explain, and this is what their dev team told me (I told them my height and weight-5'7" and 173lbs):
I estimate passive calories for [Questionfear] around 1840kcal (roughly as I don't know her age). The [Device] will not display less than this when being worn, as it displays overall calorie consumption of passive+active calories. When [Questionfear] physically moves and works out, a number of 3,000 seems reasonable.

Additionally, [Device] does not correlate steps and calories. So, with moving your wrist quite a lot and not walking much (weight training) it is possible to reach more calories than actually walking.

I am at a loss as to how any of this adds up. Anyone have a good grasp on how they're getting these numbers?

Replies

  • senecarr
    senecarr Posts: 5,377 Member
    That doesn't seem a reasonable result.
    Plugging it in at IIFYM's TDEE calculator, putting you as lightly active and doing 30 minutes of moderate exercise a day, it estimaes your TDEE at 2149.
    http://www.iifym.com/tdee-calculator/
    I'm a man around 5'8", 180 lb, and 3,000 calories in a day according to my Fitbit Charge HR happens around over 10k steps.
  • snowflake930
    snowflake930 Posts: 2,188 Member
    Doesn't add up. Way high.
    I get 18-20K per day and do not burn that many calories..............just saying, something is wrong with their figuring. IMHO (fit bit user here)
  • questionfear
    questionfear Posts: 527 Member
    Thank you both! I thought the same thing (and also ran a TDEE calculation) but was worried maybe there was another angle I wasn't seeing. It's definitely super wonky.
  • neohdiver
    neohdiver Posts: 738 Member
    Seems a bit high.

    1840 would be the calories you burn, no matter what.
    6k steps is roughly 3 miles - at a casual pace at your weight, that would be around 292 calories
    30 minutes of bodyweight workout at your weight would be around 330 calories.
    Total - 2462 calories.
  • nordlead2005
    nordlead2005 Posts: 1,303 Member
    Based on your stats, you have a BMR of ~1515. Lightly active (1.4x multiplier) gives 2121 calories/day, and moderately active (1.55x multiplier) gives 2348 calories/day. Assuming you are accurately representing your daily activity, I would expect it to fall somewhere in that range. Their estimate of 1840 seems spot on for a sedentary person, but it seems they are over amplifying the activity.
  • questionfear
    questionfear Posts: 527 Member
    nordlead2005 wrote: »
    Based on your stats, you have a BMR of ~1515. Lightly active (1.4x multiplier) gives 2121 calories/day, and moderately active (1.55x multiplier) gives 2348 calories/day. Assuming you are accurately representing your daily activity, I would expect it to fall somewhere in that range. Their estimate of 1840 seems spot on for a sedentary person, but it seems they are over amplifying the activity.

    I agree. I think they're basically assuming two things: That all activity picked up by the device is above and beyond my normal calorie burn, and that the activity they're picking up is worth far more calories than they think. I wouldn't consider 6k steps to be above and beyond, since it was my normal everyday stuff like walking the dog, but if they're counting that as above and beyond, plus inflating the caloric burn, I can almost see their logic.

    It's still very wrong, though.

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