Messed up exercise calories burned

[BostonLove]

Why does my Fitbit think that I burn less calories if I run 25 minutes then if I run 24 minutes? When I put in 24 minutes it says I burnt 209 calories. When I put in 25 minutes it says I burned 198 calories. The very fundamental principle of exercise is that the longer you do it the more calories you burn. This happens all the time when I run - for example you burn more calories if you run 21 minutes then if you run 23. Can Fitbit please fix this? It drives me nuts!!

[JohnnyRow]

"The very fundamental principle of exercise is that the longer you do it the more calories you burn."

Another basic premise is that you burn more calories when you exercise more intensely.  It sounds like you are adding this workout after-the-fact rather than actually recording the run as it happens.  I don't understand the reason for that, but anyway it depends on all the parameters you entered for logging the run, not just time length.

[Heybales]

I'm curious how you are entering this too.

So manual entry it sounds like, entering time so must be entering distance too.

Same distance either case - 25 min, or faster run to get the same distance in 24 min.

https://exrx.net/Calculators/WalkRunMETs

If pace is kept the same the extra min does indeed add calories.

But if you correctly change the pace for the shorter time, then bam.

A very fundamental principle of exercise is that if you do it more intensely you burn more calories per time.

Now, it's very minimal difference - because frankly for running or walking, it's about the same calorie burn per distance no matter how long it takes.

There is difference though.

https://exrx.net/Aerobic/WalkCalExp