Fitbit accuracy for your daily exercise?

Christismylife

I just got a Fitbit. I have been on MyFitnessPal for years, and I have usually always guessed at my activity level when putting in my goals. Then I just add in exercise and eat my exercise calories. Currently I think I have it set for the lowest level/sedentary.

So yesterday I did 16,000+ steps and at the end of the day MyFitnessPal gave me over 1,000 calories extra for the day. Can I treat these like I used to treat exercise calories? Does MyFitnessPal take into account my goals I have inputted if losing weight when it imports my calorie adjustments from Fitbit or is the adjustment supposed to be for maintenance eating? Hope this question makes sense.

neldabg

You must set both FitBit and MFP goal settings to weight loss to receive the proper adjustment.
Personally, I would trust my numbers that I calculated from years of data over what FitBit calculates. One reason some people gain weight while using trackers is that they fail to account for potential errors and eat more than they should for their activity. If FitBit's added calories match what you would've calculated, then great. If not, you can always tweak your stats on FitBit until the numbers match or just disconnect FitBit from your MFP account and calculate what you know is right.
I am female, 5'2", in my 20's, and maintain a range of 108-114 lbs. In my experience, FitBit is fairly accurate at predicting my TDEE up to, I want to say, 10-15k steps. Past a certain threshold, it calculates about 200 calories too much. This information is what I've gathered after several months of my own weight and intake calculations. I love hitting step goals and I still use FitBit to help me estimate my TDEE and for the challenges, but I do pay attention to real world results.
Beware: MFP will usually add more calories than FitBit calculates based on its prediction of how active you'll be for the rest of the day. You should go by however many calories *FitBit* shows you have left on the app or Dashboard.
Also, be mindful of false steps. Some people take bumpy commutes or move their arms a lot (i.e cashiers) which leads to people thinking that the extra steps and thus the extra calories are correct.

janejellyroll

Some people find that their Fitbit takes a week or so to adjust properly, so it's possible that that you'll see lower adjustments going forward.

If everything is working correctly, you can treat those exercise calories (it's what they are). Some people find that their Fitbit activity adjustments are very accurate (I'm in this group), while others find that it over-estimates (or even under-estimates) their needs.

MFP is considering your goals when making the adjustment -- it's giving you an adjustment to put you back to net your original calorie goal (so if you have it set to a deficit, the adjustment will leave you at a deficit). I personally don't pay any attention to how many calories Fitbit tells me I have left or burned -- I let MFP do all the adjustments (sometimes they'll give me different numbers for how many I have left and that's okay -- it's the MFP number that really counts here).

That said, if you've been using MFP for years, you already have a good database of information on how much your body needs. Is 1,000 a lot more than you would usually eat back for a day with as much activity as you had yesterday?

PAV8888

16000 steps would bump you just above mfp's very active setting. So, if hesitant, just use mfp's very active setting for that day.

The goals sections are irrelevant for integration to work properly at end of day, midnight.

MFP and Fitbit integration compares values and adjusts based on TDEE values at midnight.

Yes. Tdee.

MFP compares the expected end of day value including logged exercise to the Fitbit tdee value and spits out an adjustment.

This adjustment is off of the expected mfp value, therefore it already takes your desired deficit into account.

This does not make it right or wrong. only observation over time can determine the relative accuracy of your tracker given your type of activity and way of logging.

Nony_Mouse

I'm another who goes by what my Fitbit gives me, though that is based on experience, and in fact recent experience says it may be underestimating a little.

Unlike Jane though, I pretty much ignore MFP and go by my Fitbit exclusively. Easier to work out how many more cals I'll burn for the day an hour or so before bed than to work out how many MFP may claim back. MFP is a handy quick indicator of if I'm in the red and should maybe think about moving though.

janejellyroll

Nony_Mouse wrote: »

I'm another who goes by what my Fitbit gives me, though that is based on experience, and in fact recent experience says it may be underestimating a little.

Unlike Jane though, I pretty much ignore MFP and go by my Fitbit exclusively. Easier to work out how many more cals I'll burn for the day an hour or so before bed than to work out how many MFP may claim back. MFP is a handy quick indicator of if I'm in the red and should maybe think about moving though.

Whether you choose to go by Fitbit or MFP, I think there is a lot to be said for picking *one* to pay attention to and not flipping back and forth between the two. Trying to make both "happy" would be overwhelming for me.