Calories - Fitbit vs equipment

[Gryzor]

Hello everyone!

I was wondering, which one should I believe regarding my burned calories - my Ionic or my elliptical? For instance, my last (quite short) workout bagged me some 350kCal according to my elliptical, but only 260kCal according to my Ionic. The same was true with my previous elliptical, and with the combo of previous elliptical/Charge 2.

On one hand, I guess the elliptical knows how much power it takes to move; on the other hand, the Ionic reads what I'm doing, so...?

Thanks for listening!

[WavyDavey]

Hi @Gryzor,

In that case, I would tend to favor the Fitbit numbers, which are based on your profile info such as height and weight, that the elliptical wouldn't know offhand.  Fitbit is also using your actual heart rate to determine exertion levels.

Also, it makes sense to use the Fitbit calories for consistency's sake, since the tracker is going to provide calories burned 24/7.

[Gryzor]

Well, even though I tend to agree (and thanks for the reply 🙂 ), I'm still a bit hesitant. I think it boils down to pure physics as well? I mean, my elliptical even measures watts and it makes it more apparent - it *knows* how much energy it takes to move those pads! So to some degree the output (my body's energy) and input (the pressure on the machine) should probably match.

Regarding HR -another issue here- what is the actual correlation between HR and calories burned? I mean, if I get fitter and my workout HR  goes down, ceteris paribus, would it mean I burn less calories? Or (here's something interesting), how about this: my new elliptical, much more expensive and better designed and built, makes it easier to achieve higher speeds and HR. However the perceived exertion is the same as before, so....?

It's all a bit baffling if you ask me, and arguments in favor of any which point are equally logical, I think...

[WavyDavey]

Well ultimately it probably doesn't matter. A difference of 100 calories in a workout isn't significant enough to have a big effect on your weight management plan. So really, there's no way to know.

I find where elliptical and treadmill machines have an advantage is in measuring distance. Since you're not actually moving through space, the Fitbit has to do guesswork to determine distance on those.

I still think HR is a better measure than the machine. Just because it takes X amount of power, doesn't mean much. If I'm very strong or in good condition, I don't exert myself as much as someone just starting out. Same power output on the machine can require different amounts of exertion to achieve it.

Which is the excellent point you made, that we all have to deal with. When first starting out in fitness, there's a high heart rate and slow heart rate recover, so it's easy to burn an excess of calories. Once we get fit, it becomes easier work and fewer calories burned. Then we have to look at things like going longer or going more intense with the exercise. I've had to go from walking to biking to interval sprints to keep the ball rolling. The law of diminishing returns is real, and depressing. 🙂