Can we talk Fitbit cal adjustments?

tyh428

So, I'm confused I use my Fitbit during the day and it's adding more calories.. but my activity so far today has just been normal walking around for my job..which would be calculated as being lightly active..so I wouldn't want to dip into those calories right?

janejellyroll

If your Fitbit is synced and you have set MFP to "lightly active," it will only begin adding activity adjustments when you go *over* the amount of activity estimated for the "lightly active" activity level. If you are getting adjustments, it means that you have moved more than MFP would have estimated for your activity level. Using them wouldn't be "double dipping."

amyepdx

Be sure to enable negative calorie adjustments so you start out in the red until you get in your basic activity as it's set to your level.

inertiastrength

I have myself set as sedentary but I adjusted the calories UP from what MFP gave me so I don't double dip but I'm still synched. If you are using the mfp recommended cals, you can safely eat back at least 1/2 imo

PAV8888

janejellyroll wrote: »

If your Fitbit is synced and you have set MFP to "lightly active," it will only begin adding activity adjustments when you go *over* the amount of activity estimated for the "lightly active" activity level. If you are getting adjustments, it means that you have moved more than MFP would have estimated for your activity level. Using them wouldn't be "double dipping."

**QFT**

amyepdx wrote: »

Be sure to enable negative calorie adjustments so you start out in the red until you get in your basic activity as it's set to your level.

It is a good idea to do this for the days when you might never get to up to the level of activity you told MFP you always do. For example if you regularly get "0" Cal fitbit exercise adjustments, chances are good you would actually get a negative adjustment if you had negative adjustments enabled.

**However you would still not get positive adjustments till you exceeded MFP's prediction**, i.e. no double dipping with integration working properly.

About the only thing that can trip you up here is if you regularly go to bed/become couch potato level sedentary long before midnight.

Fitbit assigns you 1.0x BMR calories per minute of inactivity when you're not registering any movement/activity.

However during the "exercise adjustment" calculation, MFP assumes that you will continue to burn calories at your selected basic MFP rate all the way to midnight.

The MFP base rates are calculated as 1.25x, 1.4x, 1.6x, and 1.8x BMR calories per minute depending on whether you have told MFP you are sedentary, lightly active, active, or very active.

So, if you go to bed long before midnight Fitbit will only log 1.0x BMR calories, while MFP is expecting you to log at least 1.25x BMR calories.

So your "exercise adjustment" will basically reduce (you will lose "exercise" calories) at a rate of 0.25, 0.4, 0.6 or 0.8x BMR calories per minute of inactivity.

Note that I use the term "exercise" because the adjustment, in truth, is not an exercise adjustment. It is a daily TDEE adjustment to equalise your selected/stated MFP activity to what your Fitbit has detected your activity to be for the day.

As such the % of real error of the estimate is not at all related to the accuracy of exercise estimates.
But it is related to the quality of both your food and exercise logging and to whether you are "average" or a statistical outlier when it comes to the rate you normally burn calories.

My opinion is that you should trust your tools to more or less work and adjust in 3-4 weeks based on your actual results which you should evaluate using a trending weight app or website.

This is coming from someone who has calculated that my Fitbit over-estimates me by about 5.5%, which in my case ends up being between 150 and 200 Cal a day.

Maxematics

Your screenshot says that your negative calorie adjustments are disabled. You're going to want to enable those ASAP.

ent3rsandman

janejellyroll wrote: »

If your Fitbit is synced and you have set MFP to "lightly active," it will only begin adding activity adjustments when you go *over* the amount of activity estimated for the "lightly active" activity level. If you are getting adjustments, it means that you have moved more than MFP would have estimated for your activity level. Using them wouldn't be "double dipping."

Out of curiosity, what is considered lightly active? My fitbit does this too, but I have MFP set to sedentary because I don't like to eat back my exercise calories. I do LISS cardio 3 days a week and alternate it with bodyweight/dumbbell resistance training, so six days a week I always do something that takes at least 45 minutes to complete. There are some days where I'll laze around the house until it's time to work out though, and there's always a day on the weekend where I do nothing but sit on my butt.

SusanMFindlay

ent3rsandman wrote: »

janejellyroll wrote: »

If your Fitbit is synced and you have set MFP to "lightly active," it will only begin adding activity adjustments when you go *over* the amount of activity estimated for the "lightly active" activity level. If you are getting adjustments, it means that you have moved more than MFP would have estimated for your activity level. Using them wouldn't be "double dipping."

Out of curiosity, what is considered lightly active? My fitbit does this too, but I have MFP set to sedentary because I don't like to eat back my exercise calories. I do LISS cardio 3 days a week and alternate it with bodyweight/dumbbell resistance training, so six days a week I always do something that takes at least 45 minutes to complete. There are some days where I'll laze around the house until it's time to work out though, and there's always a day on the weekend where I do nothing but sit on my butt.

Lightly Active is about 5,000-8,000 steps/day. I believe people who set their activity level to Lightly Active typically start to see positive adjustments at about 5,000-6,000 steps. (I'm set to Active and start to see positive adjustments at around 8,000-10,000 steps.) The exact point at which you start to get positive adjustments will depend on what kind of steps you're taking (leisurely saunter vs. hill walking or stair climbing) and how late in the day you hit that step count.

To the OP: If you have a job that involves a fair amount of time on your feet (or are on your feet a lot outside of work), MFP may dramatically underestimate your calorie burn. As someone who teaches for a living, I'm supposedly "lightly active". In actual fact, I'm more than "very active". FitBit has been a godsend for letting me estimate my real calorie burns.