The "Eat half your calories back" rule explained??

RobD520
RobD520 Posts: 420 Member
edited November 17 in Health and Weight Loss
I was looking back at another tool I have used for fitness tracking and noticed the following difference in the results logging a pretty common workout for me (Walking-4.5 MPH 60 minutes):

MFP allows me to eat back a straight 514 "calories burned".

The other tool does the following calculation for the same workout:

431 (calories burned during the activity)
-118.8 (calories I would have burned at my "non-exercise" activity level)

=319 calories available to eat back.

This seems to explain why the other tool was so much more accurate for me than this one. Unfortunately, MFP has so many features that I am not willing to give it up.



Replies

  • MelanieCN77
    MelanieCN77 Posts: 4,047 Member
    Same as above poster, I track my activity with a device and allow that to import to MFP. Over time you really get to know which burn is a realistic report and which are overdoing it, by how much of the calories you eat back and what your weight does. "Eat half back" just builds in room for error, the margin of which in MFP's numbers is really quite large.
  • StaciMarie1974
    StaciMarie1974 Posts: 4,138 Member
    The eat 50% rule is not a rule. More a general suggestion. Many around MFP forums will recommend one eat back only a portion of their 'exercise calories' because its easy to overestimate calories burned. So eating back a portion would help offset that pitfall.

    In reality its a matter of trial and error. Pick something and try it for 4-8 weeks. If you lose faster than expected, eat more back. If you lose slower, eat less.

    And of course, if you feel your calorie burn # is fairly accurate, do what you think is best for you.
  • Tacklewasher
    Tacklewasher Posts: 7,122 Member
    I started eating back ~ half, and lost weight faster than intended (15 lbs a month) but was morbidly obese, so it wasn't a worry. Now that I'm just obese, I'm watching how fast I lose and and am eating most of the calories I earn through exercise.

    But 2 things.
    1. I have an activity tracker and between it and MFP, the adjustment above is taken into consideration.
    2. I adjusted the amount I ate back based on experience with the tracker. Doing primarily cardio, I find I need to eat them all back to hit (not exceed) my goals. If I start a different exercise routine, I will probably bank 25% until I'm comfortable with the burn calculation.
  • annacole94
    annacole94 Posts: 994 Member
    For some reason, when MFP takes my activity from Google Fit, it disregards half the data and assigns me too many calories. I bike to work, but I'm slow. I go 3.85 km in about 18 minutes. MFP likes to tell me I'm going 12-14 mph, when it's really under 10. It likes to try to give me 200 calories, when Google Fit estimates 80-100.

    And that's why I adjust those workouts down. I tend to leave my "steps" bonus intact, and eat more of that, as it seems to be a more realistic estimate.
  • DanyellMcGinnis
    DanyellMcGinnis Posts: 315 Member
    This "rule" was never going to work for me. There are days I do over 1000 calories worth of exercise. No way am I going to eat only 500 calories back.

    When I was losing, I stuck to maybe 100-200 calories below what MFP suggested after exercise (most days I would do 700-800 calories worth of exercise, as judged by the database). I averaged a little under a pound a week over about 50 weeks, for a total of 45 pounds lost. If I had been doing a lot less exercise, maybe eat 50% less would've worked. But I had the time and inclination to do more (so I could eat more!) and I did just that.

    Now that I am in maintenance, I eat pretty close to what MFP says. I know there is error involved, both in CI and CO, but I am staying within my maintenance range so eating everything back is working for me.
  • fitmom4lifemfp
    fitmom4lifemfp Posts: 1,572 Member
    RobD520 wrote: »
    I was looking back at another tool I have used for fitness tracking and noticed the following difference in the results logging a pretty common workout for me (Walking-4.5 MPH 60 minutes):

    MFP allows me to eat back a straight 514 "calories burned".

    The other tool does the following calculation for the same workout:

    431 (calories burned during the activity)
    -118.8 (calories I would have burned at my "non-exercise" activity level)

    =319 calories available to eat back.

    This seems to explain why the other tool was so much more accurate for me than this one. Unfortunately, MFP has so many features that I am not willing to give it up.



    MFP does not force you to eat anything. It's completely up to YOU if you want to eat those exercise calories. Many don't. I don't even look at that number. If I am hungry, then I eat.
  • Tacklewasher
    Tacklewasher Posts: 7,122 Member
    Quoting this from another thread, because I like it so much.
    Silentpadna wrote: »
    I look at CICO as math also. As a previous poster mentioned, there are many variables on each side of the "equation". I quoted the word equation, because to me it is a simple one, but the variables make it much more complex. Things like varying rates of change in the body's complex processes, like digestion efficiency, water retention, effects of sleep, stress, and many others. In engineering, you can calculate things out to a minute level of detail and find all sorts of ways to be more accurate. Many applications, you can go through all of that, only to find out that when you reach the top of the mountain, waiting at the top is the approximation with its estimates and fudge factors and everything else.

    The point is that you won't know the 50%, 75% or 100% accurately ever. You need to adjust to see what gives you the weight loss you need. I may be eating ~100%, but should be eating only 80% and stop underestimating my food by 20%. So if I was closer on my food, I'd have to eat less of the exercise calories. But in the end what I am doing is working and giving me around a 2lb average that I am shooting for. And that is the best anyone can do, giving the unpredictable nature of human bodies.

    So some, even with the same body size etc. and the same fitness equipment, may need to treat these different. My thought is start at 75% and work up or down as needed over time.
  • Geocitiesuser
    Geocitiesuser Posts: 1,429 Member
    The calorie burns in the MFP database are ABSURD. I have seen people log things like, "XX burned 500 calories doing 15 minutes of vacuuming" and I'm like... WTF.

    I guestimate my calorie burns best I can and manually enter them. I'd rather underestimate than so grossly over estimate.
  • zyxst
    zyxst Posts: 9,149 Member
    I use ShapeSense calculators and manually enter my exercise on MFP, adjusting what MFP says to match what SS says.
  • naomillion
    naomillion Posts: 351 Member
    Hi Rob!
    I just read this article yesterday. Maybe it helps :smile:

    http://www.shapesense.com/fitness-exercise/articles/net-versus-gross-calorie-burn.shtml
  • KettleTO
    KettleTO Posts: 144 Member
    annacole94 wrote: »
    For some reason, when MFP takes my activity from Google Fit, it disregards half the data and assigns me too many calories. I bike to work, but I'm slow. I go 3.85 km in about 18 minutes. MFP likes to tell me I'm going 12-14 mph, when it's really under 10. It likes to try to give me 200 calories, when Google Fit estimates 80-100.

    And that's why I adjust those workouts down. I tend to leave my "steps" bonus intact, and eat more of that, as it seems to be a more realistic estimate.

    Ah metric, I too have that problem. It is because you were going 12.8 km/hr and it can't do unit conversion. I just unsync'd MFP and GoogleFit again becuase the correction wasn't worth the autolog. I just log myself now.
  • Christine_72
    Christine_72 Posts: 16,049 Member
    I think 50% is a starting point, and adjust up or down from there. Ideally we'd all be eating 100% back. But unfortunately ci and co calculations are often not perfect, so for some it's safer to leave a bit of a buffer behind
  • RedheadedPrincess14
    RedheadedPrincess14 Posts: 415 Member
    I have just recently realized that no matter how hard I try, I eat back all my exercise calories. At my height (5"8.5) a weight of around 135, a general intake of 1290 a day, there is just not way to not eat back those calories. I couldn't exercise until very recently because I fractured my patella in January but if I don't eat back those calories, I get so angry. Psychological maybe? I do t know but working just seems to make me so hungry
  • Christine_72
    Christine_72 Posts: 16,049 Member
    RedheadedPrincess14 wrote: »
    I have just recently realized that no matter how hard I try, I eat back all my exercise calories. At my height (5"8.5) a weight of around 135, a general intake of 1290 a day, there is just not way to not eat back those calories. I couldn't exercise until very recently because I fractured my patella in January but if I don't eat back those calories, I get so angry. Psychological maybe? I do t know but working just seems to make me so hungry

    I'm 5"8 and my goal weight was 143lbs, it was incredibly hard and required constant vigilance to stay there, so i upped it to 147-149lbs and this suits my natural appetite much better.

    I tried the 1200 thing once, and lasted 3 miserable days. There is no way, no how i could manage on such a low calorie allowance day in day out, I'd 100% end up binging before long.
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