Logging calories burned with HIIT

[Kiraa]

Hi! I'm having difficulty figuring out how I should log calories burned doing HIIT. I do orangetheory fitness which requires a heart rate monitor, at the end of the class you get your stats including how many calories you've burned. About half of the class is on a treadmill plus various body weight exercises, rowing etc. I wear my fitbit to class to log the steps, but it doesn't pick up the full calories burned due to the nature of the work out. Should I note how many calories burned I have logged prior to class, subtract those from what I log after class and take that fitbit total from the orangetheory fitness report to figure out the difference? I.e. Prior to class I've burned 600 calories according to fitbit, after class fitbit reports a total of 800 burned, OTF reports I burned 600 during my workout leaving a total of 400 calories I need to manually log. Sorry if this is confusing, I'm starting to confuse myself 😅

[Dominique]

How long are your HIIT sessions and what Fitbit are you using? 800 calories sound quite high for a female in anything less than an hour long, and a one-hour HIIT session sounds very long (by definition, HIIT is something so intense you can’t sustain it for very long). I would just keep whatever calories Fitbit said I burned, and if it’s more than that in reality, I would view the extra calories as a bonus. There are 24 hours in a day, and what you do in 30 minutes (no matter how intense it is) can’t make that much of a difference anyway.

[Kiraa]

I just pulled those numbers for an easy example, I usually burn around 620 for a hour work out, fitbit logs around 300 or so. Thanks for your input!

[iMike]

I had the same problems with my Fitbit when I did Orangetheory.  I absolutely loved OTF, the blend of high-intensity interval cardio and then the second half consisting of strength training.  The heart-rate monitor they strap around your chest usually recorded (depending on how hard I pushed myself during the cardio portion) between 600-800 calories burned after the full hour was complete.  My Fitbit never tracked with the chest strapped heartrate monitor.  Since my hour was tracked with a heart-rate monitor I just started removing my Fitbit for that hour and then adding my recorded calories burned manually.  Personally I think the discrepancy comes from the second half of the class that focuses on strength training.  Some of the movements for those exercise don't seem to track particularly well with Fitbit.

It's too bad OTF is expensive; it's one of the few exercise programs I enjoyed enough to stick with.  I should find a way to get back to it.