Accuracy of Fitbit calories burned

carrieraeg
carrieraeg Posts: 7 Member
in Health and Weight Loss
What's everyone's knowledge/opinion on how accurate Fitbit HR is with calories burned? I've read before that it underestimates calories burns (when would be okay for me) and just want to know everyone's thoughts.

I aim for a 1,000 calorie deficiency per day and usually eat anything from 1,200-1,500 calories depending on what I do that day. I'm 23 5'3" and about 180lbs and work retail so I'm always standing/walking around. On a day where I work but do no other exercise (I pace around and do stairs a lot at work) it says I burn about 2,500-2,800 calories how correct does this sound?
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Replies

  • malibu927
    malibu927 Posts: 17,562 Member
    Follow your logging and results for 4-6 weeks then adjust as needed. Though a 1000-calorie deficit at your size is pretty aggressive. I'd probably drop it to 500-750.
  • Bxqtie116
    Bxqtie116 Posts: 552 Member
    The calories you burn account for the energy it takes for your body to function. When you walk or exercise, it adds to it. Our numbers are about the same (height & weight) and I have mine set at a 750 calorie deficit for the day. When I workout, my deficit ends up being at least 1000.
  • ForecasterJason
    ForecasterJason Posts: 2,577 Member
    I'm not sure if it's different for the HR model, but I have the One and I think it overestimates my calories burned.
  • DaddieCat
    DaddieCat Posts: 3,643 Member
    I have the surge, and it drastically over estimates my calories... but that's with the hr most likely going crazy during lifting which it's not designed for.
  • AverageJoeFit
    AverageJoeFit Posts: 251 Member
    I agree that fitbit calories are over estimated I have been maintaining my weight for about 4 months and have never eaten all the calories that my fitbit says I should.

    I just go with what MFP says and leave it at that.
  • StaciMarie1974
    StaciMarie1974 Posts: 4,138 Member
    My One seems fairly accurate. (No experience w/ the wrist models.) When I hit maintenance weight, I learned that if I ate below my TDEE according to Fitbit that I continued to lose weight.
  • mommazach
    mommazach Posts: 384 Member
    102 Calories burned in a mile for walking 4mph. You'd have to walk about 19.6 miles to get the 2,000 calories burned. I'd start checking the app settings for walking, or use another app like Map my walk, to get a better idea of the actual calories also. Don't give up on your Fitbit, but don't think of it as the most accurate measurement you can.
  • StaciMarie1974
    StaciMarie1974 Posts: 4,138 Member
    edited February 2016
    Fitbit cals burned are all day/TDEE including BMR. Not just for exercise/miles walked. Example I'm at 1299 right now, 6:50 pm. Its not 1299 'exercise' but 1299 total from all sources.

    PS cals burned for any activity will depend on the person's stats. And for walking, also incline or not. A mile at 4mph for me is only about 75.
    mommazach wrote: »
    102 Calories burned in a mile for walking 4mph. You'd have to walk about 19.6 miles to get the 2,000 calories burned. I'd start checking the app settings for walking, or use another app like Map my walk, to get a better idea of the actual calories also. Don't give up on your Fitbit, but don't think of it as the most accurate measurement you can.

  • Pawsforme
    Pawsforme Posts: 645 Member
    I believe if anything my Charge HR slightly under estimates my TDEE.
  • Christine_72
    Christine_72 Posts: 16,049 Member
    I have the fitbit zip, as the only exercise i do is walking, so a HRM would be a waste for me.

    Yesterday I did 21,621 steps (10.6m) and fitbit estimated my TDEE at 2,706... So yeah... Can't say I 100% trust it.
  • StaciMarie1974
    StaciMarie1974 Posts: 4,138 Member
    That is VERY active. What is your BMR?
    Christine_72 wrote: »
    I have the fitbit zip, as the only exercise i do is walking, so a HRM would be a waste for me.

    Yesterday I did 21,621 steps (10.6m) and fitbit estimated my TDEE at 2,706... So yeah... Can't say I 100% trust it.

  • Christine_72
    Christine_72 Posts: 16,049 Member
    edited February 2016
    StaciMarie1974 wrote: »
    That is VERY active. What is your BMR?
    Christine_72 wrote: »
    I have the fitbit zip, as the only exercise i do is walking, so a HRM would be a waste for me.

    Yesterday I did 21,621 steps (10.6m) and fitbit estimated my TDEE at 2,706... So yeah... Can't say I 100% trust it.

    According to Scooby workshop, and lightly active, My BMR is 1424- TDEE 1979

  • jeepinshawn
    jeepinshawn Posts: 642 Member
    edited February 2016
    Christine_72 wrote: »
    StaciMarie1974 wrote: »
    That is VERY active. What is your BMR?
    Christine_72 wrote: »
    I have the fitbit zip, as the only exercise i do is walking, so a HRM would be a waste for me.

    Yesterday I did 21,621 steps (10.6m) and fitbit estimated my TDEE at 2,706... So yeah... Can't say I 100% trust it.

    According to Scooby workshop, and lightly active, My BMR is 1424- TDEE 1979

    If you are walking that much everyday you are more than lightly active Imo
  • Christine_72
    Christine_72 Posts: 16,049 Member
    jeepinshawn wrote: »
    Christine_72 wrote: »
    StaciMarie1974 wrote: »
    That is VERY active. What is your BMR?
    Christine_72 wrote: »
    I have the fitbit zip, as the only exercise i do is walking, so a HRM would be a waste for me.

    Yesterday I did 21,621 steps (10.6m) and fitbit estimated my TDEE at 2,706... So yeah... Can't say I 100% trust it.

    According to Scooby workshop, and lightly active, My BMR is 1424- TDEE 1979

    If you are walking that much everyday you are more than lightly active Imo

    I try to get there everyday, but there are days like today when I've only done 12,000 steps. So the low days balance out the higher days
  • scolaris
    scolaris Posts: 2,145 Member
    Today my Fitbit HR told me I burned 2864. I walked over 19k steps and lifted weights for 30+ minutes. I hoped telling it I'm 1" shorter than I really am would help but now in worried...
  • PAV8888
    PAV8888 Posts: 14,133 Member
    edited February 2016
    From December 2, 2014 to October 7, 2015, a period of 309 days that saw me moving from 224.7 lbs to 169.7 lbs and performing a total of 5 DXA scans, using the assumption that 1lb of catabolized lean mass is 1500 Cal and 1lb of fat mass 3500 Cal, ignoring <0.4lbs of bone mass changes, and making the assumption that my MFP logging is 100% accurate (which we KNOW it cannot be), that DXA scans are 100% accurate (fat % can be +/-1% from what is calculated) and assigning ALL discrepancy between expected and actual loss to Fitbit's TDEE calculation, the Fitbit started the time period by under-estimating TDEE by 0.5% and ended the time period over-estimating TDEE by 5.5%. Each scan showed a progressive increase to the over-estimation.

    These observations tend to confirm my belief that there is a degree of adaptive thermogenesis and increased adaptation to exercise that has taken place as weight loss and deficits have persisted.

    It also tends to confirm my belief that for all intents and purposes the bloody Fitbit (in conjunction with careful MFP logging) is remarkably bloody accurate if you are not an outlier.

    So, to start, and absent your own data, just assume the darn thing is accurate! You paid good money for it, give it a chance!

    Use a trending weight program that should probably be www.trendweight.com since you are using fitbit.com and can automatically connect the two accounts in less time that it took you to read this post.

    Every month or so, compare your trending weight to your expected weight loss for the time period (hint click on your fitbit.com profile pic and look at the calories in-calories out graph for the past 30 days) and adjust your expectations and/or your deficit based on the results you've observed!

    (and watch out for days where MFP-Fitbit integration isn't working and you have to manually correct wrong entries)

    And while you're at it OP: cut your deficit to 500 Cal as you are currently cutting way more than 20% of your TDEE.

    ETA: while obese I was aiming for a deficit of 25% of TDEE (and achieving slightly less than that). This was tapered to 20% when I became overweight. Since July I am aiming for a deficit that is closer to 10%. Note that my TDEE during the 10 months in question ranged from just over 3500 to just over 3100.
  • lemonychild
    lemonychild Posts: 654 Member
    I have my settings under sedentary and i find it very accurate.
  • Rimfakse
    Rimfakse Posts: 25 Member
    I had the HR for about 9 months before I upgraded to the Surge. I found the HR pretty accurate, but when I did sports that involved using my hands (skiing, horseback riding, even hiking...most sports apart from running basically), it underestimated the calories burns. I use a H7 Polar belt now for everything apart from running/walking.
  • dollydiva2
    dollydiva2 Posts: 71 Member
    I've just checked my BMR and TDEE on scoobysworkshop and they are pretty much exactly the same as I'm getting from my Charge HR. The BMR is slightly different at 1418 (scoobys) and 1358 fitbit but the TDEE is around 2100 on both.
  • pasudeep
    pasudeep Posts: 5 Member
    PAV8888 wrote: »
    a period of 309 days that saw me moving from 224.7 lbs to 169.7 lbs

    Impressive!

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