Fitbit WAY over estimating calories i think

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jackslovely
jackslovely Posts: 45 Member
in Health and Weight Loss
I have looked around both on here as well as on Fitbit's community forums and I am having a hard time trusting my Fitbit calories adjustment to MFP. I know Fitbit includes total calories and not just active calories but what it is computing seems overly way too high.

For example today as of right now I have taken 13,385 steps ( including 1 hour on the treadmill where I alternated walk/run for 20 minutes and then the remaining 40 was walking at a 3.8 pace).

The extra exercise calories MFP is giving me is 991.

My stats are: Female/29/201lbs with a desk job where I sit apx 10 hours a day with a few "walks" here and there. I do go to the gym 5 days a week for 1 hour and alternate strength training and the cardio description above.

Does that extra calories seem correct or where should I be looking at to adjusting the output.

Replies

  • nicholem8710
    nicholem8710 Posts: 3 Member
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    What do you have your activity level set to? If it’s set to sedentary, I wouldn’t be surprised if that added exercise was correct. I have mine set to active, take anywhere from 12000 to 18000 steps a day at work and hit the gym a few times a week. Always have at least 600 exercise cals added. Been eating to that goal (so eating back all exercise cals in addition to my base cals) and have been losing weight as expected. I have a Charge 3 for what it’s worth.
  • Duck_Puddle
    Duck_Puddle Posts: 3,237 Member
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    If you’ve set yourself to sedentary, that doesn’t seem far fetched. Best guess is that you’ve taken about 5K steps (not including your workout) already-which is a little more than sedentary for an entire day-and depending on your time zone, you might still have a good portion of the day left to go. So I don’t think the adjustment seems unreasonable.

    You can always choose to follow it or eat 1/2 of it or some other amount. After doing that for 4-6 weeks, if you’re losing faster than expected-eat more.
  • cwolfman13
    cwolfman13 Posts: 41,867 Member
    edited January 2019
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    I don't have mine synced, but from what I understand, when Fitbit syncs with MFP, it's taking a snapshot in time and extrapolating that out to the rest of your day. So, for example, it's not necessarily giving you 991 calories for that specific activity...it's also extrapolating that out and estimating your activity for the rest of the day based on what you've done so far. It is my understanding that the next time it syncs it will likely downgrade that estimation if you've just been sitting around at work. Perhaps someone else can clarify that, but that's my understanding. Also, if you've set yourself to sedentary that doesn't seem too crazy...it's not just giving you your workout calories or step calories, it's saying, "you're not remotely sedentary."

    How long have you been using it...your Fitbit will also "learn" you.

    I just use my Fitbit and look at my calories total day to day...they are fairly regular in that I typically burn anywhere from 2800-3200 per day total which jives fairly close with my real world data as I typically drop about 1 Lb per week eating 2300-2500 calories per day.
  • debtay123
    debtay123 Posts: 1,327 Member
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    I usually only eat back a portion of my calories- not the whole amount. But like they said you will have to see how it works for you.
  • PAV8888
    PAV8888 Posts: 13,939 Member
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    How many calories is MFP active or very active for you?

    What would be the Fitbit adjustment from those instead of from sedentary?

    Depending on how your movement is spread throughout the day your steps could easily represent enough activity such that it could correspond to the calories near the top end of active / bottom of very active....
  • callsitlikeiseeit
    callsitlikeiseeit Posts: 8,627 Member
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    mine rarely gives me more than 400 calories even on a workout day. for ME - thats pretty accurate.

    the fitbit does seem to be really accurate for some people, and not so much for others. why that is, i dont know.
  • manderson27
    manderson27 Posts: 3,510 Member
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    This is my experience with Fitbit Charge 3 It was kind of accidental but has been quite interesting,

    I got my Fitbit Charge 3 at the end of October and have worn it every day. During Nov and Dec I was eating back most if not a bit more of the calories it gave me. I too thought the burn was very high but thought I would try this as an experiment and because I knew I would be eating more anyway during christmas holiday.

    I was averaging around 1800-2000 cals burned a day depending how active I was, which was not very apart from some walking. During that time my weight stayed fairly stable and just went up and down the same couple of pounds. So basically I maintained for two months.

    Then after Christmas my fitbit stopped syncing with the Fitbit APP so didnt have any info to send to MFP. I just ate to the calorie goal MFP gave me or slightly over and ignored the burn on the Fitbit. I started losing weight again almost 4lb this month so on target for a pound a week.

    So yes I think it is on the high side. But knowing I can maintain by eating Fitbit calories will be very useful when I get to goal.

    It is a matter of trial and error until you find your own balance.
  • mikea2g
    mikea2g Posts: 384 Member
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    I just did a breakdown of my calories consumed vs what Fitbit said I burned for my completed days in January.

    I’m trying to lose 2 pounds per week and based off all the numbers as well as my current weight this morning vs weight on 1/1 Fitbit is overestimating my total calories burned by 26%

    This could be off for several reasons. Maybe I’m having a water retention day. Maybe I’ve put on a little muscle. My logging is very accurate and I’ve been steadily losing weight for 6 months.

    I received my Fitbit on Christmas so don’t have any data before that.

    Assuming my calories in and weight loss numbers (which I know) for the last 6 months, and assuming my average burn in January according to Fitbit is representative of my average burn for the previous months, Fitbit is overestimating my calories burned by 22%.

    I think you just have to run some numbers after you’ve had it for awhile and see what the margin of error is for you. I’ll run the numbers again the end of February to see if Anything changes. For now I just adjust my calories based on an overage of 22%.

    Today, I just synced my Fitbit with MFP and I received an extra 2000 calories to reach my 1000 calorie deficit. Basically Fitbit is saying I’m projected to burn 5000 calories today. Which really means I’m likely to burn 3900 calories. Which means I really get an extra 910 calories above my 1990 MFP gives me. It’s an extra step but seems pretty reliable for me.

    In case it matters I’m 6’4”, 239, male, 39 years old and have my MFP setting set to light active. Today I did a ton of exercise in and out of the gym. Racked up around 25.000 steps.
  • AnnPT77
    AnnPT77 Posts: 32,863 Member
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    callsitlikeiseeit wrote: »
    mine rarely gives me more than 400 calories even on a workout day. for ME - thats pretty accurate.

    the fitbit does seem to be really accurate for some people, and not so much for others. why that is, i dont know.

    That's the very nature of statistical estimates.

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