Calculation on base metabolic rate WAY off

Options
michaeljosephmoreau
michaeljosephmoreau Posts: 9 Member
in Health and Weight Loss
Hi there. I'm a 34 year old male, 259lbs, 5'7", and am mostly sedentary. Going off of that info MyFitnessPal says that I burn like 2073 calories a day. I just wore a heartrate monitor for the last 24 hours to check that calculation and with only about 30-40 minutes of moderate exercise yesterday I am right at the 5000 calorie mark for the 24 hour period.

I am not overly muscular, though I would say that I probably have more muscle than most guys of the same height and weight. My heart rate isn't super high either, it hovers at about 80-85 most of the time. I'm just astonished that I burn that many calories with little/no activity. Have any of you checked your BMR with a heartrate monitor and found it to be so far off?
«1

Replies

  • DeguelloTex
    DeguelloTex Posts: 6,652 Member
    Options
    You are not, in any way whatsoever, burning 5000 calories a day with 30-40 minutes of exercise. Or you're about 10 standard deviations from the mean. I'm going with the former.
  • DemoraFairy
    DemoraFairy Posts: 1,806 Member
    Options
    MFP says you burn 2073 calories a day? Are you sure that's not what it thinks you need to eat to lose weight? I put your stats in and got 2,590 calories a day for how many it thinks you burn.
  • msf74
    msf74 Posts: 3,498 Member
    Options
    michaeljosephmoreau wrote: »
    I just wore a heartrate monitor for the last 24 hours to check that calculation and with only about 30-40 minutes of moderate exercise yesterday I am right at the 5000 calorie mark for the 24 hour period.

    Did you use a HRM or an activity tracker (which may or may not have a HRM function as well) to get to the 5,000 calorie mark?


  • LKArgh
    LKArgh Posts: 5,179 Member
    Options
    Unless you are spending several hours doing high intensity exercise, you are not burning 5000 calories per day
    You need to find out how to properly use your heart rate monitor (which btw is supposed to monitor heart rate and does not provide accurate calorie burns - but in any case it is not that inaccurate).
    Maybe you have entered your weight in kgr?
  • diannethegeek
    diannethegeek Posts: 14,776 Member
    Options
    Did you use a heart rate monitor that's designed for something other than steady-state cardio? Most of them won't give an accurate calorie estimation being worn all day like that.
  • chivalryder
    chivalryder Posts: 4,391 Member
    Options
    Heart rate monitors are only accurate when doing aerobic activity. They calculate your calorie burn based on a series of mathematical formulas, using data pulled from statistical information from various studies done on various people in various forms of exercise.

    They are designed to get an accurate(ish) burn between 70-80% of your max heart rate. Outside of this range, they get inaccurate. The further away from this range, the less accurate.

    Sitting on your butt and sleeping is not exercise, therefore, the heart rate monitor is going to be wildly inaccurate.

    But hey, go ahead and stat eating 5000 calories a day. Let us know how that works for you.
  • senecarr
    senecarr Posts: 5,377 Member
    Options
    If your resting heart rate is 80 to 85, there's a chance that the HRM's calculations are assuming you're in a fat burning zone when you're just resting.
  • Ilikechips2
    Ilikechips2 Posts: 7 Member
    edited September 2015
    Options
    .
  • michaeljosephmoreau
    michaeljosephmoreau Posts: 9 Member
    Options
    thank you. "stick in the mud" isn't how I'd describe that asinine comment. this is not the place to be so negative, go somewhere else dude.

    it's a Polar FT4. as for my BMR I calculated it both here and on some other sites online and always get around 2000 to 2100 calories per day, which seems insanely low to me. I've always been one to lose weight extremely fast when I restrict my calorie intake so I deduce the actuality of it to be somewhere in the middle of what MFP says and what the tracker says.

    going off of past weight loss when using MFP to track calories and what I've just learned I'd estimate that my actual resting metabolic rate must be somewhere around 2750-3250 calories per day, depending on level of physical activity. I do have rather dense musculature for someone who does practically no strength training at all, that's the only explanation I can find for the variation. doing the "2 pounds a week" on MFP usually results in more like 3 pounds a week for me.
  • DemoraFairy
    DemoraFairy Posts: 1,806 Member
    edited September 2015
    Options
    But you don't use BMR to work out how many calories you should eat to lose weight - you use TDEE. BMR are the calories you'd burn if you were in a coma. Your TDEE will be a lot higher (as you say, closer to 2750, as I said earlier, MFP gives 2590 for your stats), and that's what you need to eat a deficit from to lose weight.
  • LKArgh
    LKArgh Posts: 5,179 Member
    Options
    michaeljosephmoreau wrote: »
    thank you. "stick in the mud" isn't how I'd describe that asinine comment. this is not the place to be so negative, go somewhere else dude.

    it's a Polar FT4. as for my BMR I calculated it both here and on some other sites online and always get around 2000 to 2100 calories per day, which seems insanely low to me. I've always been one to lose weight extremely fast when I restrict my calorie intake so I deduce the actuality of it to be somewhere in the middle of what MFP says and what the tracker says.

    going off of past weight loss when using MFP to track calories and what I've just learned I'd estimate that my actual resting metabolic rate must be somewhere around 2750-3250 calories per day, depending on level of physical activity. I do have rather dense musculature for someone who does practically no strength training at all, that's the only explanation I can find for the variation. doing the "2 pounds a week" on MFP usually results in more like 3 pounds a week for me.

    You are confusing BMR with TDEE
    Your BMR might be 2000 and your TDEE 3000.
  • MarziPanda95
    MarziPanda95 Posts: 1,326 Member
    edited September 2015
    Options
    michaeljosephmoreau wrote: »
    thank you. "stick in the mud" isn't how I'd describe that asinine comment. this is not the place to be so negative, go somewhere else dude.

    it's a Polar FT4. as for my BMR I calculated it both here and on some other sites online and always get around 2000 to 2100 calories per day, which seems insanely low to me. I've always been one to lose weight extremely fast when I restrict my calorie intake so I deduce the actuality of it to be somewhere in the middle of what MFP says and what the tracker says.

    going off of past weight loss when using MFP to track calories and what I've just learned I'd estimate that my actual resting metabolic rate must be somewhere around 2750-3250 calories per day, depending on level of physical activity. I do have rather dense musculature for someone who does practically no strength training at all, that's the only explanation I can find for the variation. doing the "2 pounds a week" on MFP usually results in more like 3 pounds a week for me.

    Firstly, nobody said anything negative. Being truthful does not equal being negative. Secondly, what you said that I have bolded implies that you are confusing BMR with TDEE. They are not the same thing at all. Thirdly, if your BMR were actually 3000 then you would lose more than 3lbs a week doing the 2lbs a week on MFP - because that would mean that your TDEE would be very high. People who weigh more will always lose more to start with. I lost 3lbs a week for a few weeks when I started, and I was only 210lbs. It doesn't mean that your BMR is more than the calculators say.
  • Packerjohn
    Packerjohn Posts: 4,855 Member
    Options
    To be honest if you have a sedentary job and do no strength training you do not have a dense musculature.
  • sijomial
    sijomial Posts: 19,811 Member
    Options
    You can't use a HRM like that!!
    Completely the wrong tool.
  • MrPriolos
    MrPriolos Posts: 17 Member
    Options
    chivalryder wrote: »
    Sitting on your butt and sleeping is not exercise, therefore, the heart rate monitor is going to be wildly inaccurate.

    But hey, go ahead and stat eating 5000 calories a day. Let us know how that works for you.
    This is funny. :p
  • DeguelloTex
    DeguelloTex Posts: 6,652 Member
    edited September 2015
    Options
    michaeljosephmoreau wrote: »

    going off of past weight loss when using MFP to track calories and what I've just learned I'd estimate that my actual resting metabolic rate must be somewhere around 2750-3250 calories per day, depending on level of physical activity. I do have rather dense musculature for someone who does practically no strength training at all, that's the only explanation I can find for the variation. doing the "2 pounds a week" on MFP usually results in more like 3 pounds a week for me.
    You do not, in any way whatsoever, have a 3250 RMR.

    A pound of muscle burns few calories a day. I'd look somewhere else for the error in your numbers.
  • michaeljosephmoreau
    michaeljosephmoreau Posts: 9 Member
    Options
    ok, let me clarify. I'm not whatsoever suggesting a change to my allotted calories.

    I'm just trying to get a more accurate read on how many calories I am actually burning during the course of a day just so that I'll know for my own edification :)

    and sorry, but MFP gives me 2073 for my specs no matter how many times I plug it in, so does the other online calculators, and that seems mighty low.
  • DeguelloTex
    DeguelloTex Posts: 6,652 Member
    Options
    michaeljosephmoreau wrote: »
    ok, let me clarify. I'm not whatsoever suggesting a change to my allotted calories.

    I'm just trying to get a more accurate read on how many calories I am actually burning during the course of a day just so that I'll know for my own edification :)

    and sorry, but MFP gives me 2073 for my specs no matter how many times I plug it in, so does the other online calculators, and that seems mighty low.
    It isn't low. I'm 6'9" 220-225 and mine is about 2100.

    You aren't burning 5000 calories a day. You aren't burning 4000 calories a day. Chances are, with 30-40 minutes of exercise, you aren't burning 3000 calories a day, though you might be somewhere in that ballpark.

  • 3bambi3
    3bambi3 Posts: 1,650 Member
    Options
    michaeljosephmoreau wrote: »
    ok, let me clarify. I'm not whatsoever suggesting a change to my allotted calories.

    I'm just trying to get a more accurate read on how many calories I am actually burning during the course of a day just so that I'll know for my own edification :)

    and sorry, but MFP gives me 2073 for my specs no matter how many times I plug it in, so does the other online calculators, and that seems mighty low.

    If you want accuracy, go and get a DEXA scan. Heart rate monitors are not meant to be used in the fashion you used yours, and the results are not at all accurate.
  • Protranser
    Protranser Posts: 517 Member
    Options
    Why not just weigh and log your food and drink over a month, and check your weight each week. Then, try reducing your calories by 500 a day to see what that does to your weight over a month?

Categories