Why Calories burned were reduced after logging activity?

[EverOptimistic]

I spent a couple of hours cleaning windows on Saturday. The outdoors part of that work involves climbing ladders and using devices on a long pole, quite hard on arms, shoulders and back. Chores done, I happily synced my Fitbit Alta and logged my work as "cleaning". And what happens? The calories used count of the day went DOWN! Disappointed! I never actually noticed that before, but decided to check it this morning after a short workout with weights. Yup, same happened, lower calories count after registering activity.

How come? Does the app always register the exact same amount of energy spent when I register an activity manually, no matter the intensity? Will an hour of cleaning be counted the same for light dusting as for my rather workout-ish window cleaning?

Moderator Edit: Updated Subject For Clarity.

[MakMak]

Hi, @EverOptimistic! If you're creating an activity for that timeframe, Fitbit uses an estimate of calories burned for it. If you just use the information from your tracker, it's factoring in your movement and (I assume, since I don't know which tracker you have) your heart rate. If you want to have the more accurate calorie count from your tracker and still register an activity, track the activity from your tracker (use something like "workout" and you can rename it after).

[JohnnyRow]

If you manually logged your activity, that overwrites the data that was already there for that time period.  It sounds like you might have logged it as less strenuous than fitbit had already measured it.  The only reason to manually log an activity is if you did not wear the tracker.

[RobertoME · Accepted solution]

Hi there @EverOptimistic welcome aboard to the Fitbit Community and thanks for your insight @MakMak and @JohnnyRow!

@EverOptimistic, note that previous suggestions are accurate and it might be the explanation why your calories went down the day you were doing your house chores. The best in this situations is to let your tracker read  your activity normally. Also depending of the tracker you are using, perhaps starting an activity before you do your chores (Workout) in order to categorized that period of time, under the exercise history of your Dashboard.

For more information, please refer to this help article: How do I use exercise apps and modes on my Fitbit device?

See you later and stay tuned if you have other questions.