Does MFP include calories you'd have burned off anyway?

danhuckle

Apologies if this question has been asked many times before but I can't find an answer. If I swim for an hour and have burned off 600 calories is that on top of the calories I'd have burned anyway (e.g. 700 calories in total?)

MargaretYakoda

MFP calculates your base calories using the information you provided. If you’re sedentary that assumes I believe 3000 steps per day and nothing else.
Think desk job and then home to maybe putter around the house and then watch tv.

Beyond that MFP adds calories when you (or a fitness tracker that you have linked) add an exercise.
You can manually enter an exercise at the bottom of your daily food log.

This article may help you

https://support.myfitnesspal.com/hc/en-us/articles/360032623871-What-is-the-Calorie-Adjustment-in-my-Exercise-Diary

AnnPT77

I'm not sure I understand where you got that 100 calories. You burned more than 100 calories that day outside of the swim.

We burn calories:

1. Just being alive daily, breathing, heart beating, not even moving. This is "basal metabolic rate" (BMR)
2. Moving around in daily life on an average day, such as tasks at our job, chores at home, grocery shopping, cleaning, dressing, all that kind of routine stuff
3. Doing intentional exercise

You seem to be asking if MFP knows about more than the intentional exercise? Am I misunderstanding you?

When we join MFP, it asks us about things like our age, height, weight. It uses that to estimate item #1 above, our BMR.

It also asks us about our activity level, using examples that (they hope) let us know they want to know about activities on the job, doing home chores, and the other things that might be included in #2 above. It uses this information, plus the BMR it estimated, to estimate our "non-exercise activity thermogenesis (NEAT)", which is a combination of #1 and #2 above.

It also asks us about our weight goals, i.e., do we want to lose, maintain or gain weight, and if it's lose or gain, how fast we want to shoot for, like a pound/kilogram per week or whatever. It uses that to calculate our calorie deficit our surplus. Let's focus on deficit, i.e., weight loss. Our calorie deficit is how many fewer calories our goal should be than the sum of #1 & #2 above, in order to trigger weight loss at the requested rate.

So, just using round numbers for an example, let's say that for me #1 (BMR) is estimated at 1000 calories, and #2 (my daily life stuff) is estimated at 800 calories. That would mean MFP thinks if I did no exercise, and ate 1800 calories per day, I would stay at my current weight.

If I told MFP I wanted to lose a pound a week, it would subtract 500 calories from that 1800 calories to trigger weight loss, with 1300 calories as the result. That means MFP thinks if I eat 1300 calories each day, I'd lose a pound a week.

Good so far?

Then, one day I go for a swim (or some such) and burn 200 calories. That means that on that particular day, #1 is still 1000, and #2 is still 800, but we need to add the 200 to the calories I'm burning that day. In total, MFP now thinks I burned a total of 2000 calories that day rather than 1800. Since I told it I wanted to lose a pound a week, 500 is still the right calorie deficit to subtract, in order to calculate my calorie goal. That means that day's calorie goal needs to be 2000 minus 500, which is 1500.

It handles this in practice by saying "hmm, I told Ann to eat 1300 calories a day in order to lose a pound a week, but today she burned an extra 200 calories. I'm going to tell her to eat 1500 calories today, so that she can still expect to lose a pound a week."

Does that make sense? Does that answer your question?

Bottom line: If all the estimates are accurate, we can eat back our exercise calories, and lose weight at the rate we told MFP we wanted. Some days we eat more because we moved more (exercise). Some days we eat less because we moved less (no exercise).

cmriverside

I think they probably were talking about the calories they use every hour, regardless of exercise. So, is the exercise actually burning (say) 300 calories, or is 100 calories of that what they would be burning as part of their baseline RMR.


...and I don't have the energy to try to explain it.

So I'll just say, no. :flowerforyou: or maybe yes.

Please elaborate on the question, @danhuckle.

AnnPT77

Ah, thanks, @cmriverside, that makes sense as an interpretation.

If that's it, @danhuckle, you'd ideally log net exercise calories when manually logging exercise. That ideally would be gross exercise calories minus BMR calories minus MFP's assumed basic life activity calories (NEAT).

In practice, that's probably not the worst issue with the MFP exercise database calories, and it is more of a problem in some cases than others.

Also in practice, I wouldn't personally worry about it, unless a person has either a very, very high total number of exercise calories, many more than average; or does a lot of very long but low-calorie-burning activity they want to log, like very long periods of slow walking.

In the overall context, the gross to net difference for typical exercise (half an hour 5 days a week or whatever) isn't super meaningful arithmetically in the big picture, IMO. (Opinion based on around 9 years of logging experience as a more exercise-active than average woman.)

In your specific case, without more details, I'd be more inclined to question the 600 calories than worry about the 100 calories. I'm not saying it's wrong, because some strokes at some paces at some body sizes for some duration will get you there. I don't know how long you swam, how fast, using what stroke, at what body size. But 600 calories for an hour of (anything) is a fairly high burn, and many people are swimming no longer than that at a time.

There exist some online calculators that use METS (same research-based methodology MFP uses), but let you specify some of those variables more precisely. You could consider using one of those for comparison. If you're getting the gross calories from a tracker, there's some evidence that they estimate swimming calories less well than they estimate some other activities. (Many of them now will back out BMR and give you a calorie estimate net of BMR. They don't back out the MFP activity level calories. Syncing a good tracker will effectively back out both.)