Fitbit, iphone steps, NEAT and calorie adjustments... ahhh

emmylootwo

I don't know what I'm doing!! Lol!

I just bought a new Fitbit Charge 3 and I just don't understand how the calorie adjustment works. I have walked around 5700 steps so far today -- tracked on both my Fitbit and my iPhone.

When I have the Fitbit synced with my MFP account, my calorie adjustment is around +1000 to my goal of 1900 (chosen for a 1000 calorie deficit and sedentary lifestyle). What the heck? No way I'm burning 2900 (BMR) + 1000 (NEAT?) = 3900 calories a day!! I know I weigh 350lbs but come on! Plus I have the Fitbit set up as sedentary too so that, reportedly, it doesn't estimate how many calories I will burn later in the day -- only real time cals.

When I unsync Fitbit and sync my iPhone to MFP instead, my calorie adjustment is +200 calories. This sounds pretty reasonable to me!

I thought I might just ignore the whole calorie adjustment thing altogether, but then again the whole reason I bought the Fitbit was to help increase my daily NEAT and track my deficit.

Haha oh gosh. I'm in way over my head, aren't I? Can someone explain this to me? I want to figure it out so I can stick to it long enough to lose weight and re-evaluate in 4-6 weeks.

witchaywoman81

If you've walked 5700 steps already today, you aren't sedentary. I would say that's at least lightly active. For perspective, I try to get at least 10,000 steps/day, have my account set to "very active" and still often get a couple hundred added calories to the baseline that MFP gives me.

Also, make sure you have your account set to enable negative calorie adjustments if you don't already, especially if you're planning to have your Fitbit synced throughout the day.

Duck_Puddle

So how it’s supposed to work...

Mfp assumes you’re going burn a certain amount without exercise based on your settings, activity level. This is your NEAT.

Mfp then takes that number and creates a calorie goal based on your weight loss/gain/maintain settings.

So your neat is 2900. Mfp assumes you (as sedentary) will burn this much without any exercise.

Mfp gave you a calorie goal of 1900 (1000 less than your NEAT).

Whenever you do exercise (or activity above the sedentary level-which is under about 4000 steps a day), you should log that activity and eat the additional calories - because you’ll still maintain the 1000 calorie deficit. Your TDEE would be your NEAT +
the extra activity.

When you add a Fitbit to the mix, rather than logging activity on mfp, you allow your Fitbit to estimate your overall activity for the day.

Fitbit sends over your total calories burned for the day (TDEE). Mfp subtracts that number from what it assumes you’ll burn all day (your NEAT). The difference is your Fitbit adjustment-which should theoretically be the same as the amount you would log manually in MFP if you didn’t have a Fitbit. The Fitbit just takes the guesswork out.

Fitbit is only sending over your TDEE (actual thus far in the day and a projected amount for the entire day-regardless of sedentary or otherwise). That’s it.

If you’re set as sedentary on mfp and you walk more than 4K steps a day, your adjustments will likely be larger than you’d think they should be (since some of what you’re getting as an adjustment is what should be included in a higher activity level). It really doesn’t matter since the numbers will be the same.

Some things that can complicate this:
1 it can take Fitbit some time to adjust to your normal activity levels so sometimes the overall daily projected total is a bit off during the day
2 I don’t know your age or your height, but your total TDEE could easily be well over 3,000 (if your sedentary NEAT is 2900 and you’ve already walked more than sedentary number of steps).
3.i don’t know your height, but some trackers (as is also the case with many generic calculators too) are not as accurate for people over class 2 obese (by BMI).
4. Fitbits only estimate. They are going to be reasonably close for a lot of the people - but it might be high or low for you.

As with everything-all of this is a giant estimation game. Give things a reasonable try for 4-6 weeks; be as consistent as is reasonable for you. Adjust as necessary.

shadow2soul

shadow2soul wrote: »

Here is an example of how the math works:

Lightly Active MFP estimated burn (based on my stats): 1914

That breaks down to:
79.75 calories per hour
Or
1.329 calories per minute

Now as of 12:30 pm my Fitbit calorie burn is 910.

So there is 11 hrs 30 mins MFP has to estimate calories for.

11 * 79.75 = 877.25
30 * 1.329 = 39.87

910 (Fitbit) + 917.12 (MFP Lightly active estimation for remainder of day) =1827.12

So MFP is estimating that based on my current Fitbit burn and my lightly active setting on MFP that Fitbit say I burned 1827 by midnight. It uses this estimation to form an adjustment.

1827* - 1914 = -86

So currently I’m losing 86 calories. However after each Fitbit Sync, MFP will redo it’s math estimation for the day. It could increase or even decrease. MFP won’t stop this estimation calculation until around midnight when the Final calories burned # is sent over to MFP from Fitbit.

The higher your activity level setting is on MFP the higher it will estimate your remaining calorie burn and the more likely you will see a huge adjustment early in the day that decreases later. On the opposite side if you are set to Sedentary, but are actually really active you will see a large adjustment by the end of the day.

Now as a side note you might be seeing a slightly inflated calorie burn on Fitbit’s side if you’re RHR is higher than normal. You can look on the Fitbit app and see how often it’s in each “zone”. You might need to turn the HRM off.

emmylootwo

witchaywoman81 wrote: »

If you've walked 5700 steps already today, you aren't sedentary. I would say that's at least lightly active. For perspective, I try to get at least 10,000 steps/day, have my account set to "very active" and still often get a couple hundred added calories to the baseline that MFP gives me.

Also, make sure you have your account set to enable negative calorie adjustments if you don't already, especially if you're planning to have your Fitbit synced throughout the day.

Thanks! I do have negative adjustments turned on. Have you had success eating back you calorie adjustment each day?

emmylootwo

@Duck_Puddle Thanks! I'm 5'8' 350lbs and 24 years old, so I guess it is possible I burn that much... I guess I keep thinking I am my smaller self -- I used to weigh 140. I'll give it a try for a few weeks!

@shadow2soul My RHR looks good. The HRM is pretty darn accurate on me. I've been keeping tabs all day just to see.

witchaywoman81

emmylootwo wrote: »

witchaywoman81 wrote: »

If you've walked 5700 steps already today, you aren't sedentary. I would say that's at least lightly active. For perspective, I try to get at least 10,000 steps/day, have my account set to "very active" and still often get a couple hundred added calories to the baseline that MFP gives me.

Also, make sure you have your account set to enable negative calorie adjustments if you don't already, especially if you're planning to have your Fitbit synced throughout the day.

Thanks! I do have negative adjustments turned on. Have you had success eating back you calorie adjustment each day?

I usually try to eat back a portion of them, but sometimes leave a few on the table in the event that Fitbit is overestimating. I was rocking it over the summer but in the fall I fell back into my old ways. Sigh. Back on the wagon now though and determined to stick with it!

emmylootwo

witchaywoman81 wrote: »

emmylootwo wrote: »

witchaywoman81 wrote: »

If you've walked 5700 steps already today, you aren't sedentary. I would say that's at least lightly active. For perspective, I try to get at least 10,000 steps/day, have my account set to "very active" and still often get a couple hundred added calories to the baseline that MFP gives me.

Also, make sure you have your account set to enable negative calorie adjustments if you don't already, especially if you're planning to have your Fitbit synced throughout the day.

Thanks! I do have negative adjustments turned on. Have you had success eating back you calorie adjustment each day?

I usually try to eat back a portion of them, but sometimes leave a few on the table in the event that Fitbit is overestimating. I was rocking it over the summer but in the fall I fell back into my old ways. Sigh. Back on the wagon now though and determined to stick with it!

Good luck to you! I think I will try eating half the calorie adjustment back. I'm just not yet convinced my TDEE is so high! Will re-evaluate in a few weeks.

witchaywoman81

emmylootwo wrote: »

witchaywoman81 wrote: »

emmylootwo wrote: »

witchaywoman81 wrote: »

If you've walked 5700 steps already today, you aren't sedentary. I would say that's at least lightly active. For perspective, I try to get at least 10,000 steps/day, have my account set to "very active" and still often get a couple hundred added calories to the baseline that MFP gives me.

Also, make sure you have your account set to enable negative calorie adjustments if you don't already, especially if you're planning to have your Fitbit synced throughout the day.

Thanks! I do have negative adjustments turned on. Have you had success eating back you calorie adjustment each day?

I usually try to eat back a portion of them, but sometimes leave a few on the table in the event that Fitbit is overestimating. I was rocking it over the summer but in the fall I fell back into my old ways. Sigh. Back on the wagon now though and determined to stick with it!

Good luck to you! I think I will try eating half the calorie adjustment back. I'm just not yet convinced my TDEE is so high! Will re-evaluate in a few weeks.

Thanks, you too! That’s my plan as well. I need to get a few solid weeks of accurate data to see where the numbers fall. I’ve been on and off so many times I don’t feel like I have a good sense of where I’m at; however, my gut tells me that it’s relatively close, at least!