Help understanding Fitbit “adjustment”!

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Hi,

I have read all the threads I can find and I still don’t quite understand this...

My husband and I both have MFP, he has a Fitbit and I use Apple Watch. We both have daily steps set to 7000, and we both are trying to lose 500 cals per day, so I’m allowed 1200 and he’s allowed 1800 calories, and we both have MFP tracking our steps. Yesterday we went to gym, did the same workout, with slight differences in speed on treadmill, for around an hour, doing weights also. My Apple Watch said 250 cals burned and his Fitbit had 390, which is probably not unreasonable, given his weight.

So in MFP, I have 1200 goal, plus 250 exercise, so allowed 1450 calories to eat. I did also do around 13000 steps, so around 6000 more than goal, but with 30 mins on treadmill that seems reasonable. My iPhone adjustment was 0, which I didn’t quite understand as it was based on 13 calories burned (?) so just the gym calories, but it felt nice and simple to me.

In my husband’s MFP, he was given 800 odd calories for exercise, so his 390 from the gym, and the rest an adjustment. He walked around 10,000 steps. I don’t understand how he has burned 800 calories thru exercise. That would allow him to eat 2600 calories yesterday and our worry is that something is very wrong compared to my readings, and if he did eat that much he would not be losing weight.

Overall my watch says I burned around 2000 cals and the Fitbit said my husband burned 3000 for the day.

We are both set to sedentary in MFP because I think that is true for us and having read various other threads the advice seemed to be set to sedentary and add in your exercise. By exercise I understand that to mean anything over and above your normal daily activity, eg, going to the gym, or going a walk at lunchtime, so I feel that what my Apple Watch is giving me is fair and accurate.

We have now today both stopped MFP tracking steps to see what difference that makes.

I have read anything I can about the adjustments and predicting forward etc and to be honest don’t understand it and still don’t think that 800 extra calories seems right.

I am so sorry for such a long post, but would be grateful for any (hopefully) simple explantation anyone could give.

Thanks so much.

Jill

Replies

  • cmriverside
    cmriverside Posts: 34,129 Member
    edited March 2019
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    If you want simple, take the Fitbit (or Apple) off. :lol:

    I lost all my weight and have kept it off with only this website, a food scale, and a body weight scale. :drinker:
  • emilysusana
    emilysusana Posts: 416 Member
    edited March 2019
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    I have a Fitbit. The different models may yield different results (I have a Flex 2), but I have 10 weeks of data (wearing Fitbit all the time, tracking food meticulously) which says that my Fitbit tracking is dead on. I have not eaten back all my calories the Fitbit adds on, but I’ve also lost more quickly than my goal, and I’ve done the math to realize that I could have eaten back all those calories and still had a 500 calorie deficit /lost a pound a week.

    I don’t have direct experience with the Apple Watch, but I’ve considered getting one and posted a thread about it, and someone said it didn’t interact well with MFP. I think it was not adding those exercise calories to the daily allotment accurately. The person said they started tracking calories on a different site for this reason. I know that doesn’t give you an answer as to what to do, but it might help you see you’re not the first one to see this discrepancy.
  • shadow2soul
    shadow2soul Posts: 7,692 Member
    edited March 2019
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    Hi,

    I have read all the threads I can find and I still don’t quite understand this...

    My husband and I both have MFP, he has a Fitbit and I use Apple Watch. We both have daily steps set to 7000, and we both are trying to lose 500 cals per day, so I’m allowed 1200 and he’s allowed 1800 calories, and we both have MFP tracking our steps. Yesterday we went to gym, did the same workout, with slight differences in speed on treadmill, for around an hour, doing weights also. My Apple Watch said 250 cals burned and his Fitbit had 390, which is probably not unreasonable, given his weight.

    So in MFP, I have 1200 goal, plus 250 exercise, so allowed 1450 calories to eat. I did also do around 13000 steps, so around 6000 more than goal, but with 30 mins on treadmill that seems reasonable. My iPhone adjustment was 0, which I didn’t quite understand as it was based on 13 calories burned (?) so just the gym calories, but it felt nice and simple to me.

    In my husband’s MFP, he was given 800 odd calories for exercise, so his 390 from the gym, and the rest an adjustment. He walked around 10,000 steps. I don’t understand how he has burned 800 calories thru exercise. That would allow him to eat 2600 calories yesterday and our worry is that something is very wrong compared to my readings, and if he did eat that much he would not be losing weight.

    Overall my watch says I burned around 2000 cals and the Fitbit said my husband burned 3000 for the day.

    We are both set to sedentary in MFP because I think that is true for us and having read various other threads the advice seemed to be set to sedentary and add in your exercise. By exercise I understand that to mean anything over and above your normal daily activity, eg, going to the gym, or going a walk at lunchtime, so I feel that what my Apple Watch is giving me is fair and accurate.

    We have now today both stopped MFP tracking steps to see what difference that makes.

    I have read anything I can about the adjustments and predicting forward etc and to be honest don’t understand it and still don’t think that 800 extra calories seems right.

    I am so sorry for such a long post, but would be grateful for any (hopefully) simple explantation anyone could give.

    Thanks so much.

    Jill

    I actually own both an Apple Watch and a Fitbit. Both give me similar TDEE estimates and I have had the Fitbit long enough that I know it’s TDEE estimate is pretty close to my actual TDEE.

    Now here’s the thing where things get bizarre. I will get more calories with my Fitbit linked to MFP than I will with my Apple Watch. I don’t even know where MFP is getting it’s iOS calorie burned data from, because it doesn’t match anything in my iOS health app. Some days this means my adjustment is 500 calories under what it should be (so if I followed MFP + iOS adjustment I’d be undereating by a lot). MFP is the only logging app that severely cuts my calories burned from Apple Watch.

    Take Jan 24 for example:

    Apple Watch data says 956 active calories with a total calorie burn of 2536. So my TDEE estimate from Apple is 2536.

    MFP however is saying “ 133 calories burned as of 7:25 pm”.
    My activity level was set to Lightly Active which means that MFP thinks I burn 1800 before exercise.
    By only adding 133 calories back to my day my deficit is now increased by 500+ calories.

    Even yesterday I had a 2042 calorie burn from Apple Watch and only had 23 calories added on MFP (regardless of activity level....I changed it from sedentary to very active and was given 23 calories every time). The two just don’t interact well together.


  • rennies_mum
    rennies_mum Posts: 9 Member
    edited March 2019
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    I found this thread very useful... https://community.myfitnesspal.com/en/discussion/10718056/apple-watch-doesn-t-sync-like-fitb ... and have installed the Pacer app. Waiting to see what happens by end of day!

    Thanks for replies.
  • mikea2g
    mikea2g Posts: 384 Member
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    I’ve had my Fitbit for 2 months now and when I compare my intake (through MFP) with what Fitbit says I burned and my actual rate of loss, I find Fitbit is overestimating my calorie burn by about 20%.

    The Fitbit seems to be consistently reliable in its over estimate for me. I love all the data and dealing with the overestimate is not a big deal. Just a little additional math.

    So if you love the device, whatever it is, I’d do some math at the end of a week, 2 weeks and a month to see what your weight loss / gain is, what it was suppose to be based on the device info, and adjust the difference. Of course, this all hinges on wearing the device all the time an being extremely accurate with your food log.
  • PAV8888
    PAV8888 Posts: 13,943 Member
    edited March 2019
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    Calories in MFP via consistent logging

    Calories out some watch via consistent usage.

    Deficit / overage calculation over 4 to 6 weeks

    Compare to weight TREND (weight trend app; trendweight.com if using Fitbit) over same time period.

    Correction factor is now known.

    Keep an eye on it, might change slightly over time.

    Mine ranged from -0.5% of TDEE to less than 5% of TDEE over any two month period over 3.5 years of relatively careful logging.

    MFP is full of threads about incomprehensible adjustments from Apple watches.... best of luck with that :)

    A tdee of 3000 for a male who is active which is what the 10,000 steps means is far from unusual.

    MFP integration's exercise adjustment it is not related at all to exercise.

    It is a bookkeeping entry to equalize the TDEE measured by your device to the TDEE estimate that was implicit in your choice of the activity level you picked on MFP.

    If tdee for sedentary is predicted to be 2200 and your Fitbit detects 3000, you get an 800 exercise adjustment regardless of how the 800 extra calories came about and were calculated.