Should I be "eating" my exercise calories?

Honestly look through the forums. This question gets asked every other day and the answers are always the same. Rather than a yes or no answer you need to understand how it all works in respect of your deficit and the options you have, eat none, eat some eat all.

My rule of thumb is check if the exercise calorie count is accurate. In many situations it is NOT. Theres a lot of scope for the number not being correct and you eating more than you have exercised. Then its up to how I feel on the day as to whether i eat them or not. If im not hungry I dont and let the benefit go to the deficit, if I am or want a treat I do. Your choice.

MFP is designed so you have a deficit already built in before the exercise calories. Your goal should be to have net calories match the MFP number that is provided. So yes, you should be eating the exercise calories if you are following MFP as it's designed.

As stated though, exercise calories can be highly inflated on this site so most will usually just eat a portion back to be safe. Maybe 50% or so.

There are three major ways to calculate a deficit/structure a calorie-counting diet that I've seen:

(1) Figure out your overall calorie needs including the exercise you do or plan to do and then deduct the number of calories needed to lose your goal -- in other words, life plus exercise gives you maintenance calories of 2200, so to lose 1.5 lbs/week you eat 1450. (This is similar to the TDEE method people talk about. It's what I do.) If you do this you would not also eat back exercise. It's already included in figuring your deficit.

(2) If you are basically maintaining, figure out what you are eating and then plan to cut calories AND add exercise to result in the desired loss. For example, if you are currently eating 2200, you could plan to increase exercise by an average of 250 calories/day AND cut calories by 500/day for an expected loss of 1.5 lbs/week. Again, you wouldn't eat back exercise, because it's already taken into account in figuring your deficit.

(3) (the MFP way) If you aren't so sure that you will reliably exercise a particular amount or just want flexibility not to or to change it around or to adjust on days you do, figure out what you need to maintain if you did not exercise at all. Then subtract the calories needed to lose your goal--here, let's say your maintenance if you don't exercise is 1950, so you'd eat 1200 to lose 1.5 lbs without exercise. BUT if you then do exercise you'd adjust to achieve your deficit with a combination of the two, as with methods (1) and (2). So if you exercise 400 calories off one day, you'd eat 1600 to achieve the same deficit overall and still lose the 1.5 lbs.

When people try to do the MFP method (3) without eating back exercise calories and are actually logging everything accurately, they are increasing their deficit beyond what they planned for. For example, if they said they wanted to lose 1.5 lbs per week (750 calorie deficit per day) and then exercise an additional 500 calories, they are now aiming for a 2.5 lb deficit, which is generally considered too extreme for all but the extremely obese, and is greater than that achieved through the other methods that don't eat back exercise. What would make more sense is that if you plan to get half your loss through exercise and half through cutting calories (as with most who claim that eating back is counterproductive), then ask for a non-exercise based goal of only half your real goal, or here perhaps a deficit of 300-500, while planning another 300-500 of exercise per day. Or just eat back the exercise--it's the same thing.

The problem, of course, is that if you eat back exercise you have to be careful not to overestimate the exercise, but if you use one of the other methods you have to be careful not to overestimate how much exercise you will be doing.

I'm new not only to this site, but also to this way of life. I think that we need to hear how others do it, but then figure out what suits us individually.

For me, eating back the calories really varies on what kind of day or week I've had.
For instance, on Sunday I was both running and cycling, and ate only a small portion of the cals I burned.

On Monday, I didn't eat any of the cals I burnt running, but I was also far below the recommended cals for my goals, though I wasn't hungry.
Yesterday, however, I was flipping STARVING! I was cycling, though not running, and ate most of them back. I think Monday was a big factor in Tuesday's hunger.

Monday was just a silly day, and I've realised I shouldn't wait until I'm hungry to eat, just like I shouldn't wait until I'm thirsty to drink. If you wait until you're hungry, you'll eat more.

So, say for instance my cals/day are 1250, and I burn 500 cals through exercise - I'll probably eat to about 1400. So a little over the initial plan, but still below the 1750 that I've 'earned' - partly because I'm concerned that cals burned are overestimated.