Cals Burned Question: HRM v. FitBit v. MFP

Well I'm pretty sure the question has been asked in one way or another many times, but I'm gonna ask again.

I've heard many times that MFP and gym equipment are notorious for over-estimating calories burned, and that a HRM provides the most accurate estimate.

I just wanted to get some more clarity on this, because I've found the opposite to be true. My HRM generally estimates up to 110 more calories burned than MFP and my FitBit... should I record the HRM calories, or stick with MFP estimations to be safe?

Also, when using the HRM burn estimations, should I be subtracting BMR calories from the total number burned at the end of my workout, or is that already built into the equation? So, say I run for 40 minutes and the HRM reads 440 cals burned... and if I burn 1 cal per minute while sedentary, should I be subtracting that from the HRM reading for a total of 400 cals burned?

(I have a Polar FT4)

Thanks!

Replies

  • tinad120
    tinad120 Posts: 267 Member
    I believe that the HRM is the more accurate estimate of calories burned since it is a constant measure. MFP or the FitBit cannot include in its estimate the intensity of the workout.


    As for subtracting your BMR, I have never thought to do it because the difference is minimal anyway.

    Edit: Clarification
  • This is just me but I always under-estimate calories out and over-estimate calories in. That way, if I'm wrong, I'm happy with the surprise.
  • Annette8479
    Annette8479 Posts: 82 Member
    bump
  • yarwell
    yarwell Posts: 10,477 Member
    The HRM's report calories burned total during the exercise period. You would have burned at your sedentary rate during that time if you hadn't been exercising, so the sedentary cals (not just the BMR) should be subtracted.

    The accuracy of all of these things depends how well the are set up for you personally, if you haven't input your own VO2max, height, weight, HRmax etc then it'll be more general and hence less accurate than it might be.

    As an example, my cardiovascular fitness is (or at least was) in the bottom 10% of the population, so I couldn't burn 10 cals/minute for more than about 5 minutes whereas some of these estimators put me at burning 12/minute for a whole hour.
  • SomeoneSomeplace
    SomeoneSomeplace Posts: 1,094 Member
    I have a Polar FT4 as well and mine normally tells me I burn a bit more calories than MFP but not much. I can only speak from my experience as a runner because I haven't used it for much else. I find MFP to be way more accurate than the gym machine counts especially the elliptical. It tells me in an hour and 15 minutes (About an 8.5 mile run for me) I burn 890 calories, which seems like it would be accurate to me, as would mean I burn about 10 cals a minute.
    There have been reported discrepancies tho and you should not use your HRM when lifting/strength training unless you're doing something like cicuits where you don't rest.