Why is Fitbit cancelling out my exercise?

nickchristian3910
nickchristian3910 Posts: 34 Member
edited November 17 in Fitness and Exercise
Have a question about Fitbit and MFP. I have a Fitbit flex and use it for walking exercise and daily activities. I also do some cycling and log that as a manual exercise in MFP. However when I review my food table for the day they cancel each other out. Example at the moment I have 274 extra calories earned today via Fitbit. Took my flex off and went for a 40 minute cycle ride at a mild pace which if I enter into my MFP gives me 299 calories. My daily total for exercise calories burned then reads Cycling 299, Fitbit calorie adjustment -25. Surely they should combine? Daily total reads 273 which is carried over to the bottom of the food table?

Replies

  • asantoroski
    asantoroski Posts: 11 Member
    You have to put the time you cycled, otherwise it will pick whatever time and it could coordinate to when you were actually using your fitbit. I was making that mistake for a while until I figured it out. So if you cycled from 7pm to 8pm.. with no fitbit, it should calculate normal, if the cycling was entered for 6pm by mistake but you were out for a walk, the cycling will cancel out the steps because it assumes those steps are from cycling so you don't double dip. Hopefully this makes sense.
  • nortonpc
    nortonpc Posts: 7 Member
    So the fitbit tracks your overall activity. The manually logged exercise you put in, would put you over the top of its calculation, so it is making an adjustment for you, so you don't over eat.

    If you click the little tiny "i" next to the calorie adjustment it will show you what MFP and what Fitbit are calculating your total caloric expenditure to be.

    Take me for example, I have a garmin that i use for cycling. If I ride for 40 minutes that is about 500 calories. When that gets put into MFP, my fitbit will often go negative somewhere in the -250 range because it doesn't want to double count that exercise.

    I hope that makes sense. It is a good thing that it is doing for sure, don't worry about it too much.
  • Wheelhouse15
    Wheelhouse15 Posts: 5,575 Member
    Fitbit is suposed to remove the steps from any manually recorded exercise so that's probably why. The steps are still kept for recording purposes but not for calculation of your daily caloric expenditures or else it would double count.
  • nickchristian3910
    nickchristian3910 Posts: 34 Member
    Sorry still confused. To me 1+1 =2 not 0. If fitbit tells my MFP that by 2.00 pm I have earned 300 extra calories. I then go for a cycle ride which burns another 300 calories. 300+300 = 600 burned by 3.00pm not 0? If I wore the fitbit and it added 300 due to leg movement during my cycle ride fine. 600+300 -(300 adjustment) = 600.
  • MattBoySlim
    MattBoySlim Posts: 62 Member
    asantoroski wrote: »
    You have to put the time you cycled, otherwise it will pick whatever time and it could coordinate to when you were actually using your fitbit. I was making that mistake for a while until I figured it out. So if you cycled from 7pm to 8pm.. with no fitbit, it should calculate normal, if the cycling was entered for 6pm by mistake but you were out for a walk, the cycling will cancel out the steps because it assumes those steps are from cycling so you don't double dip. Hopefully this makes sense.

    Do you have to enter it on fitbit website of myfitnesspal website? I imagine the fitbit website as I don't think you enter time into myfitnesspal?
  • decblessings
    decblessings Posts: 113 Member
    I've always been told to only log my exercise on MFP if the two are linked. And make sure you're choosing the correct starting time. I've personally never had any problems with it eliminating my exercise calories.
  • Wheelhouse15
    Wheelhouse15 Posts: 5,575 Member
    nickchristian3910 wrote: »
    Sorry still confused. To me 1+1 =2 not 0. If fitbit tells my MFP that by 2.00 pm I have earned 300 extra calories. I then go for a cycle ride which burns another 300 calories. 300+300 = 600 burned by 3.00pm not 0? If I wore the fitbit and it added 300 due to leg movement during my cycle ride fine. 600+300 -(300 adjustment) = 600.

    MFP assumes that the Fitbit captured those 300 calories, or that's what it seems like. I've noticed that when I work out it subtracts the exact amount of my workout from my fitbit. I think Fitbit adds this back in on their end and ignores the steps and then pushes this back to MFP.

    As stated above, if you have entered data on Fitbit take it off and add it on MFP instead. The flow of data seems to be MFP to Fitbit, where Fitbit calculates this and then sends it back to MFP as an exercise adjustment. At least, that's how it seems to be working.
  • nortonpc
    nortonpc Posts: 7 Member
    a24nazg407xu.png

    I am probably doing a bad job of explaining this.

    You have your BMR which is what your body burns just sitting around. When you exercise and manually put the numbers in, your fitbit and the exercise would count that number twice.

    tdvq4ogpf45u.png

    In the above picture you can see where my garmin has essentially overstated the amount of calories burned and it is going to push me beyond what the fitbit thinks I have done for the whole day. If I run but I am super lazy the rest of the day, fitbit attempts to account for that.

    I think this is really a matter of what you feel comfortable with, I think that fitness trackers tend to over estimate the calories we really burn so I normally only eat back about 50% of my exercise calories. Does this help?

  • MattBoySlim
    MattBoySlim Posts: 62 Member
    I just checked clearly I am very lazy.

    My fitbit says my calorie adj is zero so far today, so i entered cycling and it gave me 270 calories in mfp and then fitbit adjusted of -34, so it did give extra calories for the exercise entering in the data via mfp.
    nickchristian3910 wrote: »
    Sorry still confused. To me 1+1 =2 not 0. If fitbit tells my MFP that by 2.00 pm I have earned 300 extra calories. I then go for a cycle ride which burns another 300 calories. 300+300 = 600 burned by 3.00pm not 0? If I wore the fitbit and it added 300 due to leg movement during my cycle ride fine. 600+300 -(300 adjustment) = 600.

    I noticed when I entered in the exercise it put the time as the time i entered it rather than when I started, so I hadn't earned the extra calories until I set the time to 1hr ago. Maybe check that?
  • weird_me2
    weird_me2 Posts: 716 Member
    nortonpc wrote: »
    a24nazg407xu.png

    I am probably doing a bad job of explaining this.

    You have your BMR which is what your body burns just sitting around. When you exercise and manually put the numbers in, your fitbit and the exercise would count that number twice.

    tdvq4ogpf45u.png

    In the above picture you can see where my garmin has essentially overstated the amount of calories burned and it is going to push me beyond what the fitbit thinks I have done for the whole day. If I run but I am super lazy the rest of the day, fitbit attempts to account for that.

    I think this is really a matter of what you feel comfortable with, I think that fitness trackers tend to over estimate the calories we really burn so I normally only eat back about 50% of my exercise calories. Does this help?

    I think this is a great explanation and break down of what happens. Something else to keep in mind is that the Fitbit calorie adjustment will change over the course of the day. Last night, when I went to bed, I was in the positive (by 5 calories) with my Fitbit adjustment based on the expected calorie burn for the day. This morning, when I woke up, I was in the negative (by 36 calories) for yesterday because I did not meet the Fitbit expected calorie burn.

    If your Fitbit gives you an extra 200 calories at 10 am because you went for a run this morning but then you sit and do almost nothing the rest of the day, by 10 pm you could see that your fitbit adjustment is -200 because at the end of the day you did not meet your projected activity. Fitbit also calculates the calories burned for activity differently than MFP does. MFP seems to do a straight activity calculation and does not include your BMR. Fitbit seems to downwardly adjust your BMR for the time spent doing the activity. This means if you exercised for an hour and would normally burn 100 calories by Fitbit calculations, you will see a -100 calorie adjustment from Fitbit. At the end of the day, though, MFP and Fitbit should match up for calories burned. On Friday, I forgot my Fitbit at home, but manually logged my steps by entering an activity that was approximate to the number of steps I got while I was out and about. Fitbit gave me a negative adjustment at the end of the day so that my MFP calories burned matched my Fitbit calories burned. I think Fitbit is generally more accurate because it does adjust for what you would have burned anyway.
  • nickchristian3910
    nickchristian3910 Posts: 34 Member
    Thanks everyone for the input.
This discussion has been closed.

Categories