Exercise calories? Again? WTF

SideSteel Posts: 11,069 Member
This is a pretty big debate that pops up continually on the main forums.

Should you, or should you not, eat back your exercise calories? The answer is: It depends.

Here are some background definitions before going into this:

BMR (Basal Metabolic Rate): The number of calories you burn at complete rest.
EAT (Exercise Associated Thermogenesis): Caloric requirements of training, or training expenditure.
NEAT (Non Exercise Activity Thermogenesis): Caloric requirements of activity that is not planned exercise. Vacuuming, driving, brushing your teeth, for example.
TEF/DIT (Thermic Effect of Feeding or Diet Induced Thermogenesis): Caloric expense of eating/digestion.
TDEE: (Total Daily Energy Expenditure) = Sum of the above. BMR+EAT+NEAT+TEF

Exercise calories, as they are typically used in MFP specifically, is represented by EAT in the above definition. Whether or not you should eat your EAT (giggity) depends on what system or method you are using to calculate your intake needs.

If you are using most other online calculation tools to determine an intake estimate, that estimate is going to already include EAT as part of the suggested intake. For example, it will ask you an activity factor that includes an average of your exercise, and with this it increases your TDEE to account for the fact that you are exercising.

If you are using MFP to tell you how much to eat, that estimate is NOT going to include EAT as part of the intake estimate.

Myfitnesspal uses a caloric estimation tool that expects you to eat back calories burned during exercise.

Consequently, MFP will essentially give you a LOWER intake estimate than an external TDEE calculator would give you.

In other words:

You tell MFP: I'd like to lose 1lb/week.

MFP says: Hey, you should eat X calories every day to lose 1lb/week.

You then decide to exercise and you burn 400 calories.

MFP says: Hey you pecker, you said you wanted to lose 1lb/week. Now you need to eat X+400 because you told me you wanted to lose 1lb/week.

So based on this:

If you are using MFP to tell you how many calories to eat, you should probably be eating back some portion of your exercise calories.

If you are using an external calculator and then customizing your intake to match that, you should not be eating back your exercise calories.

Lastly: Exercise expenditure is often over-stated.

My general opinion is that it's much simpler and uses less guess-work to use a custom intake and just forget about the exercise calorie model entirely, but that's a different topic of sorts, more discussion of which can be found here: http://www.myfitnesspal.com/topics/show/819055-setting-your-calorie-and-macro-targets


  • Giggity!
  • GuybrushThreepw00d
    GuybrushThreepw00d Posts: 784 Member
    Giggity bump!
  • fugaj01
    fugaj01 Posts: 171 Member
    awesome info SS, THanks a ton! Lots of people will benefit from this :)
  • Amazon_Who
    Amazon_Who Posts: 1,092 Member
    Thank you SS, I already knew this but now I understand it!
  • marvybells
    marvybells Posts: 1,984 Member
    thank you! this was a great post for me to use to double check my calculations. i wanted to make sure i wasn't inadvertently starving myself or eating to much. ( i had it right-phew!)
  • sundaywishes
    sundaywishes Posts: 246 Member
    I knew this, but this is the simplest way I have ever heard it explained. For that, it deserves a bump.
  • alexbusnello
    alexbusnello Posts: 1,010 Member
    Wow, thank you!

  • newjourney2015
    newjourney2015 Posts: 216 Member
  • petah1992
    petah1992 Posts: 3 Member
    this was extremely helpful!
  • MiguelX66
    MiguelX66 Posts: 24 Member
    Very helpful. This information should be a 'sticky' in the main forums,as I would think these questions come up very often. Thanks for posting it.
  • katg73
    katg73 Posts: 77 Member
    Very helpful. This information should be a 'sticky' in the main forums,as I would think these questions come up very often. Thanks for posting it.

    AGREED. I can't tell you how many people NEED to read this. I used to not eat back all my cals while being on the suggested 1200 daily limit, so I ended up netting 890-980 cals a day - worked fine for a few months... until I stopped losing coz I continued to work hard in the gym so much that my body started needing more. I've slowly increased and am starting to see them come off again and my body is healthily leaning out while my muscle builds.
  • SideSteel
    SideSteel Posts: 11,069 Member
    If you see any exercise calorie posts come up in the main forums, please feel free to link this thread as a reply if you would like.
  • CallMeCupcakeDammit
    CallMeCupcakeDammit Posts: 9,495 Member
    Bumping so my FL will see it
  • Sarauk2sf
    Sarauk2sf Posts: 28,079 Member
    ^^I just realized that I did not have this in my topics /smh
  • sozisfitnow
    sozisfitnow Posts: 209 Member
    With you on exercise expenditures is a vaguely wild estimate!
  • AmberB519
    AmberB519 Posts: 336 Member
    Bookmarked ;)
  • SteveJWatson
    SteveJWatson Posts: 1,228 Member
    I reckon you have to use your judgement anyway.

    For example: I told MFP that my job involved moderate daily exercise (I think the category included postman) - so it will generate a generalised calorie consumption for a person who walks about a bit. Of course, some days I work my *kitten* off and other days I'm just driving round checking stock or doing office work, so you have to make allowances for this.

    Ergo, I dont eat back all of my exercise calories if I have been a bit of a sloth that day. If I have worked my butt off and still made it to the gym, well...I'll eat em back.

    I was flabbergasted at how many calories i estimated I burned at the weekend (I put walking at 3.5 mph for three hours) when in reality it was more like 4 and a half, carrying various bits of kit (rough shoot) - again, I rounded down because I simply refuse to believe I burned that many calories.
  • kar328
    kar328 Posts: 4,089 Member
    bookmared, bumped and much appreciated :happy: