Can I eat my calories burned?

helen5430

maybe a stupid question, but I’m new here. If my calorie goal is 1500, but I exercise and burn 1000 calories (I run long distances) and the total now increases to 2500cal, am I “allowed” to eat over and above the 1500cal…? Not the full 1000cal amount of course, but just somewhere in between?

Lietchi

In theory you could eat the full amount even, but some recommend only eating part of those calories (at least until you find out of the numbers are correct for you).

I eat all of my exercise calories because experience has taught me that the numbers work for me (I actually burn more calories than expected, so even more margin to eat a bit more).

Where is the number coming from? For me: my Garmin underestimates my running calories. I compare with the calculator here: https://exrx.net/Calculators/WalkRunMETs

Set it to net calories rather than gross calories to know how many extra calories you can consume/ to compare with the number MFP estimates for runs.

If you're using a Garmin, compare with gross calories to know if your Garmin is estimating correctly.

csplatt

yes, that is how the MyFitnessPal calculations work. good idea to eat many of those back but not quite all — and see how it goes

yirara

Yeah, exactly. If you really burn 1000kcal from exercise each day and you ate 1500, then if you were not to eat them back that's the same as not exercising and only eating 500kcal. Nobody can live on that. However, 1000kcal for running does sound like a lot. Do check your numbers with this website: https://exrx.net/Calculators/WalkRunMETs and set your calculation to net calories.

AnnPT77

+1 to what they said. I ate every delicious - carefully estimated - exercise calorie all through weight loss, and for 9+ years of successful maintenance since.

A few things to know, though:

If you're adding exercise manually by typing it in to MFP, make sure you're not double-counting. Set your MFP activity level to your best estimate of your life excluding intentional exercise.

When you add exercise, remember that your body burned calories just being alive, and MFP assumed you burned some calories in that time-slot doing everyday humdrum stuff. Some fitness trackers only give you the gross calories for the exercise session, and the gross calories include the "just being alive" calories. (The terms basal metabolic rate (BMR) or resting metabolic rate (RMR) are the "just being alive" calories.) MFP's exercise database calorie estimates IMU double-count some of these things, too.

For short-ish exercise sessions of relatively intense exercise, the BMR/RMR calories are a relatively small concern, and even those plus the already-assumed daily life movement calories aren't major for most of us. For long exercise sessions (like multi-hour) at low intensity (like casual walking), either or both can be a bigger deal arithmetically. If you're using a tracker, consider backing out the BMR/RMR calories for a really long exercise session before logging it, or look for net calories in your tracker. With the tracker's net calories, you're still potentially double-counting the assumed daily-life-stuff calories, and that's a thing you can estimate and back out, too, though I've never bothered.

If your tracker is synced to MFP for 24x7 calorie adjustment, and you have negative adjustments turned on in MFP, the sync should take care of that arithmetic stuff to avoid the double-count.

There's still some variability in tracker estimates, with heart rate differences between people the most relevant aspect for running calories. Unless we tell them otherwise, most trackers assume one of the age formulas for HRmax, like 220-age. Around 20% or so of people differ meaningfully from the age estimates, and that can matter in a few case.

If you have a tested max heart rate, and can tell the tracker what it is, do so. There are self-tests for estimating personal HRmax, but no one should attempt those until they have pretty good base aerobic fitness/endurance, and maybe even medical clearance to do high intensity work. If a person's a serious runner, they're probably going to want to get a personalized HRmax estimate eventually, to better guide training intensities.

One of the pluses of the calculator @yirara linked is that you can set the energy box to "net" and it will exclude your estimated BMR/RMR calories. That makes it an especially good reality check, IMO.

People will probably come along to the thread and tell you never to count exercise calories. Honestly, they're just bad at math 😉, and I mean that in the kindest possible way, sincerely. Everything in this process is an estimate, including food logging, so "estimating exercise calories is too inaccurate" is an unhelpful rationalization.

There are two rational ways to consider exercise calories during weight loss: We can estimate them separately and add the exercise calories when we exercise, or we can average in our exercise calories via things like the activity level setting, then eat the same number of calories every day whether we exercise or not. MFP is designed to support the "estimate separately" method, but can work with the "average in" method.

The difference between those two is just the accounting method. Either one can work. Both have pros and cons, including potential pitfalls. One method or the other may suit an individual better, and that's fine.

Doing a very large amount of exercise, or even moderate amounts of regular but quite intense exercise, and letting that increase an already aggressive weight loss rate target? Not a good plan. High health risk. High risk of failure because the combination is just too hard to stick with. That's the only bad approach.

Apologies for the essay.

Retroguy2000

According to MFP, yes you can eat back the full 1,000. That isn't how the body works though. And you shouldn't assume that 1,000 estimate is accurate. It also doesn't take into account potential reduction in NEAT later in the day during recovery.

The safer play is eat back about 50-75% and see how you get on. Track your weight and input calories over time. If your exercise is consistent, that will inform you what your actual calorie deficit and TDEE is, and you can then adjust your input calories accordingly.

Don't count the first week of weight change when doing this though, as that can be more water loss from new diet and/or more water gain from new exercise. But after that, if you're losing 1 pound per week say, then you can conclude your TDEE is +500 above your input calories.