Figuring FitBit accuracy with the following data?

CoachJen71

I posted a similar question to the Maintenance forum, but would like a Fitbit specific answer as well if possible. I'm still trying to trust my new higher goal numbers, and knowing my Fitbit's accuracy would help with the anxiety. Thanks for your help!

I'm a 5'2.5" 44yo woman. Still not sure on goal weight. Maybe 135? (After 18 months of dieting down from 262lbs, I am still trying to wrap my head around the idea of picking a weight/range.)

TrendWeight trend: 12/5: 141.3lbs, 1/5: 138.8 (2.7lb loss)

FitBit Burn total: 68,594 (Avg 2287/day)

MFP Goal: 62,873

Gross calorie intake: 64,144 (Avg 2138/day)

MFP Net calorie intake: 41,685 (I was set for - 250, but reset it for maintenance a week or so ago.)

The following Fitbit data was gathered with my old Flex. I have switched to a ChargeHR, so am gathering more data for that.)

Steps: 513,094 (Avg 17,103/day)
Active Minutes: 2888 (Avg 96/day)

NancyN795

Doing it by averages:
Daily deficit: 2287-2138 = 149 calories
Monthly deficit: 149*31 = 4619
Expected loss: 4619/3500 = 1.32 pounds.

Doing it by totals:
Deficit: 68594-64144 = 4450
Expected loss: 4450/3500 = 1.27 pounds.

Actual loss - more than twice expected. I would say your old Flex was significantly underestimating your burn. (Or, you're overestimating your food.)

CoachJen71

Thanks so much! I will try to tighten up my logging for this month's data collection. I do think the holidays really threw off the data a bit. A lot of guesswork about what I was eating at parties and such.

NancyN795

CoachJen71 wrote: »

Thanks so much! I will try to tighten up my logging for this month's data collection. I do think the holidays really threw off the data a bit. A lot of guesswork about what I was eating at parties and such.

That'll do it! I have to admit that for holiday dinners I just threw in a big "quick add calorie" entry and hoped it was reasonable. Plus I accepted that I was going to plateau for a while. It sounds like you over-estimated. Good for you.