Ah! So Confused with Fitbit!

kschwab0203

I've just started using a Fitbit this week and still trying to figure a few things out.

Why has it taken calories away from me today? It says I've earned -68 calories from exercise. What?!?! Why???

My goal according to MFP is 1430 per day. Fitbit has been adding extra calories each day for activity which I have not been eating back. Yesterday as usual it gave me extra calories and since I wanted to indulge in 2 glasses of wine I used them. At the end of my day, when I completed my diary, it tells me I went over! In RED , like making me feel bad because I used the extra calories it was giving me! It says yesterday I burned 2198 calories and ate 1745. That's still almost a -500 deficit. SO why today is it telling my my goal is 1362???

Someone help! I don't understand.

tinkerbellang83

If you are syncing it throughout the day then it bases the calorie adjustment on your level of activity so far for that day and assumes that you are going to be at that level of activity for the rest of the day.

For example:

You may be very active in the morning and sync your fitbit at lunchtime, your fitbit then assumes a calorie burn for the whole day based on your active morning, if you are then super lazy in the afternoon, this will be incorrect and will be adjusted the next time you sync.


Your -68 calories means you have not reached your anticipated MFP activity level for the day at the last time that you synced your fitbit. A negative adjustment will then be put on your diary.

For example:

I have myself set to Lightly Active in My Fitness Pal, that gives me a slightly higher base calorie allowance and accounts for approximately 5000 steps per day from my Garmin watch before I start receiving a calorie adjustment. If by lunchtime I still only have around 1000 steps in I will receive a negative adjustment because it doesn't think I will reach 5000 steps based on the information it has at the time.

What activity level do you have yourself set at? Does it seem correct?

malibu927

When you sync your Fitbit, MFP reads the total calories you burned and estimates how much over (or under, if you have negative calories enabled) your maintenance calories you will burn if you remain that active the rest of the day. At the time of your last sync yesterday (I'm going to assume early evening?) you had so much of an adjustment because MFP thought you would remain that active, but you weren't. So when you first synced this morning it saw your total calorie burn didn't reach what it expected, so it took calories away and thus you ate over your goal. Also because you had done little but sleep in the first hours of this morning, you moved very little and thus it expects you won't reach your maintenance calories, therefore it gave you a negative adjustment. This is very common in the morning and nothing to worry about if you know you're going to be moving.

kschwab0203

Ok I think I understand the negative adjustment. But....

What I don't understand is why if I had 2198 calories out and 1745 in did it tell me I went over budget?

malibu927

2198-1745=453 calories you were in deficit. So 47 calories over your goal.

janejellyroll

kschwab0203 wrote: »

Ok I think I understand the negative adjustment. But....

What I don't understand is why if I had 2198 calories out and 1745 in did it tell me I went over budget?

What is your deficit supposed to be? If MFP thinks you want a certain deficit then you will be "over budget" even if you eat less than you burn.

kschwab0203

I'm supposed to be at 1430 calories per day. I think I get it now.

Thanks for the help!

tinkerbellang83

malibu927 wrote: »

2198-1745=453 calories you were in deficit. So 47 calories over your goal.

Also OP it's worth noting that if it's the calories burned figure you've quoted is from Fitbit, this might differ from the calories burned from MFP as they use different calculations to calculate your TDEE.

ghudson92

A general rule of thumb for the fitbit: ignore everything it tells you calorie wise! When I use my fitbit, I tend to just stick to my allotted calories, allowing myself a bit extra if I do a big workout, otherwise I just eat as MFP suggests

CyberTone

I am glad that I did not heed any naysayers' advice to ignore the Calorie estimates from Fitbit.

I eat back 100% of the Fitbit Calorie adjustment in maintenance. I ate back all of them when I was losing a few pounds and had no problem netting about 1600 Cals per day to lose those pounds when I had MFP set to lose 0.5 pounds per week.

For comparison, I am 55, 5'8", 153 lbs. and my maintenance net Calories are about 1870 at MFP Sedentary. I normally gross 2300 to 2600 Calories logged for food and earn on average about a 500 to 700 Fitbit Calorie adjustment above MFP Sedentary activity level setting.

I do use a food scale to weigh all solids, measuring cups and spoons to measure liquids, and verify all food items I log through outside web sources and Nutrition Facts labels. I trust that my Calorie Intake is pretty accurate using MFP, and I trust my Calorie Output is pretty accurate using the Fitbit Charge 2.

I would recommend reading through the first three posts in this thread on the MFP Fitbit Users group...

http://community.myfitnesspal.com/en/discussion/10098937/faq-syncing-logging-food-exercise-calorie-adjustments-activity-levels-accuracy

http://community.myfitnesspal.com/en/group/1290-fitbit-users​

MelanieCN77

Unless you have a really active job, I'd set activity on MFP to sedentary and remove negative calorie adjustments, and then just make sure to log actual exercise. That gets you a quite miserly calorie expenditure for any given day.