Fitbit Calories seem like they are way too high

shaneozouf
shaneozouf Posts: 59 Member
edited February 2019 in Fitness and Exercise
I know this gets posted on a probably weekly basis somewhere here in the MFP forums, but most of the questions are usually asking why the numbers don't match - this is not what this post is about (I understand how the syncing between MFP and Fitbit generally works). What I am looking for is a bit of feedback, I have been using MFP for the last few months and was losing weight at the expected rate (between 1 and 1.5 lbs per week) from november beginning until around end of december. I started using my Fitbit in January to help me be more active and walk 10,000 steps per day, which I have been sticking to. But the Fitbit will give me between 1200 and 1800 calories back per day, that sounds like a lot for 10,000 steps (1 calorie every 5 - 8 steps?); I do know that this has more to do with your age, weight, height, sex, etc than just calories per step, and also has more to do with the intensity of the steps.

Daily:
- Walk at a brisk pace (20 - 15 minutes/mile) for 30 minutes at one time, daily
- Get at least 10,000 steps combined by moving around, going up/down stairs, pacing around the house, etc
- Drink 150 Oz of water per day

Here are my body stats:
- Male
- 215 lb current, goal 170 lb
- 5' 8" tall
- 30 years old
- Body Fat ~30%

Here are my app/website settings:
- MFP set to sedentary, gives base calorie allowance of 1620 calories (TDEE 2370 as per MFP)
- MFP has 750 calorie deficit (1.5 lb per week)
- Fitbit tracker is Fitbit Blaze, set also to 750 calorie deficit, Heart Rate Monitor set to "AUTO"
- TDEE calculator (tdeecalculator.net) shows a TDEE of 2213 calories (https://tdeecalculator.net/result.php?s=imperial&g=male&age=30&lbs=215&in=68&act=1.2&bf=30&f=1)

If I set the TDEE Calculator from "Sedentary" (what I assume is 3000 - 5000 steps) to "Moderate" (I think this should be around 10000 steps? Maybe help me out here?), it gives me around 650 calories. This is what I should expect from the Fitbit, not 1200 - 1800.

Since I started using the Fitbit again, I have not lost weight like I expected over the last month (January), I lost about 0.5 lb instead of 4-6 lb I should lose at 1 - 1.5 lb/week (I am looking at the trend and ignoring the fluctuations).

I think it might have something to do with the Heart Rate sensor on my Fitbit, since my heart rate seems like it's always in the "Fat Burn" zone, and so all my activity is logged with a high calorie burn, for today I turned my HR sensor off just to see what the difference is, tonight, with the return calories.

I have opened my diary, does anyone have any input to offer? It would be greatly appreciated!

EDIT: I forgot to say, I use a scale to measure literally everything by weight (except liquids, which I measure by volume), and I am careful to inspect serving sizes. I have had success losing weight with MFP, in the past, but I am now struggling mostly with the fitbit

Replies

  • jtechmart
    jtechmart Posts: 67 Member
    Ok, I'm not positive on what the question is. Are you asking why is the fitbit calories burned are so high per the exercises you are doing? So, for a 30 min walk the calories burned seems too high?

    The fitbit is my constant companion and here is how I use the numbers. I don't pay much attention to if calories are too high, low, or whatever. But, if I'm consistent in my workouts over a few weeks and get results, I can then say, when the fitbit calories are x then I will get y results. It's sort of like calibrating the fitbit to my body. I find this the most effective way to use a fitness tracker.

    So, if I do a 40 min elliptical workout and fitbit says I burned 570 cals, who knows if that is accurate. But, if between MFP and fitbit I have around a 1000 cal deficit on most days, I've tested that in 4 weeks I'll drop 8-10 pounds. So, I can now work with those numbers.

    Not sure that helps, but it has worked for me.
  • lin_be
    lin_be Posts: 393 Member
    Yea it seems high and your data supports that your rate of loss isn’t what you’re especting. I don’t use a Fitbit but I generally will calculate my calories burned by walking (using sedentary because I work from home and it’s just easier for me to calculate all of my steps as exercise) using the following: .33 x my weight in lbs x my distance in miles. It’s been pretty accurate. I honestly don’t think there’s a direct correlation between Fitbit HR and calorie burn either.
  • Silent_Soliloquy
    Silent_Soliloquy Posts: 237 Member
    edited February 2019
    I have found setting your initial allotment to BMR; and eating back the activity the tracker gives you (up to your planned deficit) will be almost spot on to mfp TDEE withiut a tracker.

    Your bmr is right at 2k. So aim for 1250 plus what fitbit gives you is a good place to begin fine tuning. (You said you wanted 750 deficit)

    For the record: google says 9999 steps is lightly active and 10,000 is active.
    Sedentary is sub 5k.

    I am unsure if your device has adjustable heart rate zones. My 735xt does and it made a huge difference in accuracy.

    Also i know 2 wrongs don't make a right in calculating; but this will get you close.
  • shaneozouf
    shaneozouf Posts: 59 Member
    lin_be wrote: »
    ... I honestly don’t think there’s a direct correlation between Fitbit HR and calorie burn either.

    Yeah there is, when you look at the Heart Rate trend in the Fitbit dashboard it will tell you your "Calorie Burn per Minute" based on different heart rate ranges. For example:
    Yesterday from 2:20 to 2:25 PM, my avg HR was 78 BPM, the burn, as recorded by Fitbit was 2.7 Calories/Minute.
    Yesterday from 3:10 to 3:15 PM, my avg HR was 108 BPM, the burn, as recorded by Fitbit was 8.3 Calories/Minute.

    It seems obvious that the higher the heart rate, the higher the calorie burn, but still 1800 calories / day seems like way too much for walking around a bit.

  • shaneozouf
    shaneozouf Posts: 59 Member
    Silent_Soliloquy wrote: »
    I have found setting your initial allotment to BMR; and eating back the activity the tracker gives you (up to your planned deficit) will be almost spot on to mfp TDEE withiut a tracker.

    Your bmr is right at 2k. So aim for 1250 plus what fitbit gives you is a good place to begin fine tuning. (You said you wanted 750 deficit)

    For the record: google says 9999 steps is lightly active and 10,000 is active.
    Sedentary is sub 5k.

    I am unsure if your device has adjustable heart rate zones. My 735xt does and it made a huge difference in accuracy.

    Also i know 2 wrongs don't make a right in calculating; but this will get you close.

    I was taking a look at the heart rate settings, seems like I can set a max heart rate or one custom zone (the custom zone likely has no effect on calorie/minute calculations). In order to get custom zones closer to what other heart rate zone calculators have told me, I'd have to crank my max heart rate up, but Fitbit only allows it to go to 220.
  • lin_be
    lin_be Posts: 393 Member
    shaneozouf wrote: »
    lin_be wrote: »
    ... I honestly don’t think there’s a direct correlation between Fitbit HR and calorie burn either.

    Yeah there is, when you look at the Heart Rate trend in the Fitbit dashboard it will tell you your "Calorie Burn per Minute" based on different heart rate ranges. For example:
    Yesterday from 2:20 to 2:25 PM, my avg HR was 78 BPM, the burn, as recorded by Fitbit was 2.7 Calories/Minute.
    Yesterday from 3:10 to 3:15 PM, my avg HR was 108 BPM, the burn, as recorded by Fitbit was 8.3 Calories/Minute.

    It seems obvious that the higher the heart rate, the higher the calorie burn, but still 1800 calories / day seems like way too much for walking around a bit.

    I’ve read that the actual HR is pretty reliable, just not the energy expenditure.

    https://med.stanford.edu/news/all-news/2017/05/fitness-trackers-accurately-measure-heart-rate-but-not-calories-burned.html
  • Duck_Puddle
    Duck_Puddle Posts: 3,237 Member
    Couple of notes for you-mfp settings are for NEAT (meaning everything except exercise). So mfp assumes you’re going to burn 2370 as a sedentary person (under 4-5k steps a day). You would add all activity over that level to your mfp log (which is theoretically what your Fitbit is doing).

    10k steps a day is active. “Moderate” is probably 6-8k steps a day.

    So when using a TDEE calculator, use active as your metric. And for MFP, make sure you also use active and then add any exercise on top of the numbers it gives you.

    Now-all of these things are estimates. Mfp is an estimate, Fitbit is an estimate, TDEE calculators are estimates. I’m going to guess that once you are using the correct inputs for everything-you’re going to end up with fairly consistent estimates across the board. So your Fitbit, mfp, TDEE calculators are really all going to be giving you roughly the same number.

    If you’re not losing as expected with those estimates and you’re 1000000% sure you’re weighing your food, and logging everything exactly right-then it’s possible that you’re one of the people for whom these estimates aren’t correct.

    Real world trumps any calculator-so adjust accordingly.

  • shadow2soul
    shadow2soul Posts: 7,692 Member
    edited February 2019
    Sounds like the problem lies in that your HR is often elevated throughout the day. That will definitely cause an inflated calorie burn from Fitbit and you should see a difference if you turn it off.

    It still might overestimate slightly. It is just estimating based on the data it is collecting. For some people it will overestimate and for others it will underestimate. Then there are people who will lose/maintain/gain as expected using the estimate it gives.
  • eleanorhawkins
    eleanorhawkins Posts: 1,659 Member
    Have you set the negative calories adjustment? Can't explain exactly why that's important, but it solved a similar problem when I linked my Fitbit to MFP. It's been working spot on for me since May last year, with highly varied activity levels ranging from training for and completing a half marathon to a month's recovery after an injury. However, I do keep MFP set to 'sedentary' even though I'm far from sedentary. Everyone's different, but that is what works for me.
  • shaneozouf
    shaneozouf Posts: 59 Member
    Since I can't edit the original post anymore, I'll post an update here:

    After about half my day, I had taken around 6000 steps and my returned calories were 380, this is much more in line with what I would expect. This is after having turned off the Heart Rate feature. At this rate I expect to burn around 633 calories for 10,000 steps by the end of the day. I'll probably end up playing around with a few other settings, since the HR function is important for other things like sleep tracking.
  • sijomial
    sijomial Posts: 19,809 Member
    Don't confuse a higher heart rate with energy expenditure, they have a relationship in that when you elevate your heart rate you are working harder but the relationship of HR to accurate calorie estimates is very, very loose.

    e.g.
    My RHR dropped by over 20% from low sixties to high forties with improvements in fitness. My daily calorie burns didn't reduce just because my "pump" is working better. Ditto for HR during exercise - I can produce far more power (a true measure of energy) at the same HR as I could before.

    My suggestion though would be to stop using spoons and cups to estimate your food intake - they are notoriously inaccurate. No point focussing all your attention on trying to improve your output estimates if your input estimates are poor.
  • shaneozouf
    shaneozouf Posts: 59 Member
    sijomial wrote: »
    My suggestion though would be to stop using spoons and cups to estimate your food intake - they are notoriously inaccurate. No point focussing all your attention on trying to improve your output estimates if your input estimates are poor.

    How should I measure liquids? I already measure all solids in grams, I can't recall the last time I used volumetric measurement for anything that wasn't a liquid.
  • Silent_Soliloquy
    Silent_Soliloquy Posts: 237 Member
    sijomial wrote: »
    My RHR dropped by over 20% from low sixties to high forties with improvements in fitness. My daily calorie burns didn't reduce just because my "pump" is working better. Ditto for HR during exercise - I can produce far more power (a true measure of energy) at the same HR as I could before.

    Just for my own learning... when your resting heart rate drops it is because the heart is actually stronger ... so a pump pumps a larger volume in each pump ... yes? Not like you have less overall bloodflow.

    So it's less beats per minute, with a stronger pump. But the same energy expenditure overall, yeah?

    It is my understanding that this is why the calculators need resting and max heart rate to estimate caloric expenditure. Someone more exoert may chime in on this and correct me though .
  • kalyandc
    kalyandc Posts: 12 Member
    In my case the culprit turned out to be the wrong max heart rate value. It predicted very low max heart rate and as a result the HR zones were too low and thus the higher calorie estimates.
  • heybales
    heybales Posts: 18,842 Member
    kalyandc wrote: »
    In my case the culprit turned out to be the wrong max heart rate value. It predicted very low max heart rate and as a result the HR zones were too low and thus the higher calorie estimates.

    Yes, the HRmax is used in the calculation, along with restingHR (at least that is a measurable figure), and some other things.

    But that is only during exercise.
    But if daily activity is really sedentary and exercise is lengthy and daily and high HR - could be a bad effect.

    But if avg exercise and daily activity is busy - the % of daily calories isn't that great.
    Usually it's not like 100% inflated calorie burn.

    Fitbit and others also now include workout frequency in the formula, so it can take a couple weeks to attempt to get a better value, which also means HRmax isn't holding as much weight in the formula.
  • yirara
    yirara Posts: 9,944 Member
    shaneozouf wrote: »
    sijomial wrote: »
    My suggestion though would be to stop using spoons and cups to estimate your food intake - they are notoriously inaccurate. No point focussing all your attention on trying to improve your output estimates if your input estimates are poor.

    How should I measure liquids? I already measure all solids in grams, I can't recall the last time I used volumetric measurement for anything that wasn't a liquid.

    Where? I don't know if MFP is acting up, but your diary is empty. Yes, you can measure liquids by volume (though I use the scale for oils). Everything else on the scale in grams.

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