How Accurate Is Calories Burned?

cJOYv6881

I'm very new to MFP (2nd day), so I'm still finding my way around. I am just wondering how accurate the "calories burned" number is when I input exercises. I just did 10 minutes under "Stationary bike, vigorous effort", and it says I burned over 2500 calories. This just doesn't seem possible! I was going pretty fast, but I don't even eat that many calories in a day, it doesn't make sense to burn that all off in just 10 minutes! The read-out on the bike, by comparison, said I burned less than 50.

sijomial

You have done something wrong.

Go back and check your profile set up and your exercise entry.

punkrockgoth

sijomial wrote: »

You have done something wrong.

Go back and check your profile set up and your exercise entry.

This. But also, once you do have it set up properly, both machines and MFP tend to overestimate calories burned by anywhere from 10%-50%. If you plan on eating your exercise calories back, you may have to play with how much of them you're eating back.

cJOYv6881

I went back, deleted it, and re-entered it. This time it came up at 220 calories. That still seems high. I have never tracked calories burned before, so this is entirely new to me, but that's an entire meal worth of calories I can burn off in just 10 minutes?

cJOYv6881

punkrockgoth wrote: »

sijomial wrote: »

You have done something wrong.

Go back and check your profile set up and your exercise entry.

This. But also, once you do have it set up properly, both machines and MFP tend to overestimate calories burned by anywhere from 10%-50%. If you plan on eating your exercise calories back, you may have to play with how much of them you're eating back.

Ah ok, thanks! I'll definitely allow for a margin of error there.

daweasel

I would agree that you've done something wrong in your setup, but regardless I find calories burned is always overestimated for me. For example, I run at 10-11km/h, but if I use the activities in here compared to my heart rate monitor MFP estimates around an extra 200 cal/hour. With cycling it is even worse. I get around this by using a less "vigorous" level of activity or slower speed (I log my runs at about 8pm/h and cycling at "low" intensity or whatever it is). I would rather be underestimating than overestimating, and if I find I really need an extra snack or something I'll have a piece of fruit or a yoghurt and not worry too much about going slightly over my goal.

sijomial

cJOYv6881 wrote: »

I went back, deleted it, and re-entered it. This time it came up at 220 calories. That still seems high. I have never tracked calories burned before, so this is entirely new to me, but that's an entire meal worth of calories I can burn off in just 10 minutes?

Yep still too high - that's pro-cyclist level.
If your bike measures power output (watts typically) then go with that. You can over-write the entry that the database offers you.

By the way no-one knows anything about your fitness levels as your profile is private so what feels vigorous to you may or may not equal the vigorous setting in the database.

I can hit 800 cals in an hour but I'm also a 100+ mile cyclist.

robertw486

What he said above. Unless you are fairly fit, even the new numbers are high.

I don't rely on the MFP numbers at all. There are just too many that don't jive with the accepted calorie burns, and then sometimes the speed/effort break downs are too broad to really nail things down.

rankinsect

A lot of the error is that many machines and calorie counts are trying to estimate total calories burned over the time spent exercising (gross calorie burn), not the extra calories burned as a result of the exercise (net calories burned). So adding those to your calorie goals without adjustment can double-count your resting metabolism.