Correct calorie burn

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Leonie_M234
Leonie_M234 Posts: 57 Member
in Health and Weight Loss
I have just got a fitbit and it says ive burned 900 calories on a 160min walk.
I am a 5,9 female and weigh 166lbs.
Does this sound correct?
I am slightly in shock as my samsung health which I know is less accurate says around 500.
Do other people on here get good results from going by their fitbit data?

Replies

  • Lietchi
    Lietchi Posts: 6,175 Member
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    A formula I often see here is, for calorie burn for walks:
    Weight in lbs x distance in miles x 0.3

    That number is a net number, not including the calories you burn just by being alive.
  • brianpperkins131
    brianpperkins131 Posts: 90 Member
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    Lietchi wrote: »
    A formula I often see here is, for calorie burn for walks:
    Weight in lbs x distance in miles x 0.3

    That number is a net number, not including the calories you burn just by being alive.


    That formula was in an article from Runner's World (they've since updated the online link and removed the formulas) based on studies at Syracuse University.

    The fitbit might be reporting gross, not net, calories ... so calories just for living that nearly three hours plus calories from the walk itself.
  • Leonie_M234
    Leonie_M234 Posts: 57 Member
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    The total for the day is 1800 and the walk was 900, so not sure?
  • sijomial
    sijomial Posts: 19,811 Member
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    Are you sure that number is just for your walk or is it an adjustment for your entire day up to that point?
    Is your Fitbit synched to MyFitnessPal or not?

    If it really is just a walking estimate and not an adjustment then it's horribly inflated to a degree I suspect something isn't set up correctly. Your Samsung estimate also sounds a high estimate and probably a gross calorie estimate too (including the calories you would have burned in that time period anyway) as most apps work that way.
  • Leonie_M234
    Leonie_M234 Posts: 57 Member
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    I totally agree, although a bit of googling seems to show quite high stats too? how confusing

    https://www.health.harvard.edu/diet-and-weight-loss/calories-burned-in-30-minutes-of-leisure-and-routine-activities
  • Lietchi
    Lietchi Posts: 6,175 Member
    edited November 2020
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    When I referred to "calories burned by being alive", I wasn't referring tototal calories for the day, I was referring to BMR: you'll burn those calories no matter what you're doing.

    To give a simple (fictional) example:
    - if your BMR is 1200 per day, that's 50kcal per hour
    - so for a 3-hour walk, you'll burn 150kcal just by being alive and then a certain number of calories specifically for the walk
    - some fitness watches, apps, etc. will give a gross calorie burn (walk and 150 BMR calories), while others will give net calories (only the walking itself). That link you posted doesn't specify whether it's gross or net calorie burn.

    The formula I gave is a formula for net calorie burn. You didn't state how long your walk was. But using the formula, 900kcal would be an 18 mile walk, unlikely in 160 minutes :smiley: 500kcal would be a 10 mile walk, which also sounds on the high side for a 160 minute walk. (This is presuming the formula I quoted is correct, of course)
  • sijomial
    sijomial Posts: 19,811 Member
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    Leonie_M234 wrote: »
    I totally agree, although a bit of googling seems to show quite high stats too? how confusing

    https://www.health.harvard.edu/diet-and-weight-loss/calories-burned-in-30-minutes-of-leisure-and-routine-activities

    That is a example of of gross calorie estimates - not just for the extra energy used because people were exercising in that time period. What you would have burned in your 160 mins anyway shouldn't be double counted.

    But you haven't confirmed if your number is purely an estimate for that 160mins or if you are using your Fitbit as an all day activty tracker whick you have linked to MyFitnessPal.
  • Leonie_M234
    Leonie_M234 Posts: 57 Member
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    Thanks for replies guys! @sijomial The number is from wearing my fitbit and it's not attached to myfitnesspal.
    The data says the walk burned 900 cals and my total calorie burn so far today is 1843
  • yirara
    yirara Posts: 9,443 Member
    edited November 2020
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    Leonie_M234 wrote: »
    I have just got a fitbit and it says ive burned 900 calories on a 160min walk.
    I am a 5,9 female and weigh 166lbs.
    Does this sound correct?
    I am slightly in shock as my samsung health which I know is less accurate says around 500.
    Do other people on here get good results from going by their fitbit data?

    Fitbit also gives me crazy burns when I walk. I'd not believe it but use the university of Syracuse equation quoted above instead. What fitbit is telling you is indeed gross calories. But next to that heartrate gets mixed into the calorie calculation, and if you're unfit or just happen to have a higher than average maxHR then you get those crazy numbers. Yes, you can set a custom maxHR in Fitbit but a) this function is broken since June and Fitbit doesn't feel like fixing it and b) you still get crazy burns, if a tiny bit less crazy. So honestly, I would not believe it.

    So if you walked for 160 minutes. Lets assume at a speed of 9min/km (sorry, I'm metric), then this would be about 4 mph = 10.7 miles * 166lbs * 0.3 = 530 net calories. Still a very good burn. Provided you walked that far.
  • Leonie_M234
    Leonie_M234 Posts: 57 Member
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    @yirara Thanks! I mean I was walking quite fast? but yes makes sense, disappointing though as that equation gives around 300. This means the MFP database is totally off too?
  • yirara
    yirara Posts: 9,443 Member
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    So you walked about 6 miles? Sounds about right. But you know, walking still burns calories and is great for cardiovascular health and can make you fit*. The calories in the MFP database are generally rather high. I think (but might be wrong) that those a gross calories, converted from METs (metabolic equivalent, a measure to quantify energy expenditure in exercise). I wish MFP would be using better database entries. Oh well...

    People often overestimate calories burned from walking by a lot unfortunately. Walking on two legs is what defines us. From an evolutionary standpoint we'd not be so good at it if it burned tons of calories. Now running on the other hand.. if walking uses a multiplier of 0.3, then running uses 0.64 (0.67? around that range).

    But still, walking can make you fit and do good things for your heart. I've not been running since March for reason, but mainly walked and cycled. I'm the most rubbish runner in the world. And I still manage to run, now that I've started again. And hey, even 300 calories extra is great. If your base metabolic rate is around 1500 calories, then you've just earned an additional 1/5 of that (plus all the extras you get from all your activity). That's brilliant!
  • Leonie_M234
    Leonie_M234 Posts: 57 Member
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    Thanks I am just super shocked as I can see the net cals are so different to gross,
  • Dogmom1978
    Dogmom1978 Posts: 1,580 Member
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    Net cals are from being alive plus exercise (if you do it). So, you don’t want to count net calories when adding exercise into MFP. And yes, the database over inflates exercise also imo. I deduct 20% from what it gives me and manually put that in. I lose my expected 1 lb per week (unless I have a bad week and eat at or above maintenance).

    It will take some trial and error to figure out your average calorie burn with different exercises. In the beginning, it can be a bit frustrating but after you figure it out, it’s very useful if you want the exercise to help you stay in a deficit (and allow for some tasty desserts).

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