Overestimating Exercise Calories

nurabh94 wrote: »

AnnPT77 wrote: »

nurabh94 wrote: »

Machka9 wrote: »

yirara wrote: »

Wait! Does MFP refuse to safe if you eat 1200 calories and log a workout of say 300 calories and don't eat it back? I thought it only did this for just under eating. I'm certain I might have done that a few times in the past without problems. TO, how many calories are you consuming each day?

And @nurabh94 ... how many calories do you think you're burning?

I’m eating less than 1,200 calories based on my height and the amount I need to lose but more than 1,000 on average I think.

I would guess on average I probably burn around 300 from exercise alone, but MFP sometimes puts it up to 1,000. I’m buying a Fitbit on payday to get more accurate results and hope this finds a happy medium!

DancingMoosie wrote: »

Could you give an example of the exercise and how many calories it says you burn? You are able to manually change the calories...or you could log it as something lighter, like "aerobics, low impact" or "walking 3.0". But it would be helpful to see exactly what you are talking about.

I do HIIT twice a week (average 30 mins?), aerobic low impact exercises for about 40 mins a day (this is new and wasn’t part of my routine), and yoga at least three times a week usually an hour each, at least one session is visyana yoga which I guess works on strength. My biggest thing is I roller skate for fun but when I tried to log it it has it as 15 mins of roller skating to be burning over 100 calories, which just doesn’t sound right to me!!! There was one day when my exercise came to 1,000 calories but I just can’t believe that even when I downplay the effort and time. I don’t log walking!

I’m hoping when I get a Fitbit I’ll get more accurate results and until then only eat back maybe 25%-50% of exercise calories depending on how hungry I am so as not to hinder progress. I’m not very good at maths or understanding the intricacies of calories etc. As am pretty fresh but the numbers seem too big to be realistic.

Especially given that last paragraph, I'd point out that even Fitbits (or other trackers) are just giving you an estimate, not a measurement. It's just that it's a personalized estimate, which does offer some advantages, depending on exercise mode.

It matters a little what model/type you get, when you think about what it might be good or not great at estimating, but the HIIT for sure would be something that most trackers are unlikely to estimate very accurately.

Now, before someone chimes in with "but I lost weight fine using my tracker to estimate HIIT": I agree with @sijomial that mis-estimated exercise often gets blamed when something else is actually at play. Sometimes particular people have unreasonably high faith in parts of this picture, parts that can also be a source of variation (error). I'd go broader than he did on the potential error sources, which include:

* Person differs from average in some (unknown) way, so the base BMR estimate is materially wrong.
* Wrong activity factor selected, or selected in such a way that causes double-counting
* Fitness tracker/heart rate monitor limitations (this has subcategories of error potential but I won't go into it here)
* Imprecise food logging despite best efforts
* . . . or combinations, and more.

IMU, he's correct that MFP gives a gross calorie estimate when we'd really prefer a net estimate, but in practice, for common levels of common exercises, that difference may not be a big deal in context. (I'm not going to go into details/examples, just for reply length).

Unlike sijomial, I often suggest people start with eating back 50-70% of exercise calories if they worry about them being overestimated, but (in line with his thinking) I'm not doing this because I think it's theoretically correct. I know it's completely arbitrary. I do it because it's a simple way to get people to eat back some exercise calories, which is a health-promoting approach for anyone using a MFP-estimate calorie goal, especially if targeting an aggressive weight loss rate in the first place. Zero is the exercise calorie estimate that is always wrong, and it can in some circumstances be risky to assume zero.

In reality, I think any discrepancy could be down to other things besides exercise, but explaining all the possible reasons is complex and potentially confusing, and the core objective is just to get someone to a sensible, risk-averse but successful loss rate in practice.

What I normally tell people is something like this: "If you're worried that exercise may be overestimated, start by estimating it with a consistent method, then eat back 50-75% of that. Stick with that for 4-6 weeks, then adjust your eating to get to the right safe but satisfying loss rate."

I don't tell people to "eat back more of the exercise", because the eating adjustment based on real results is the actual answer. The source of discrepancies could be anything. In most senses, exercise calories aren't any different from tooth-brushing calories or grocery-shopping calories. The main differences are that (1) exercise is more variable in many people's lives than daily routine stuff, and (2) many beginner calorie counters start with aggressive exercise plans that peter out after enthusiasm fades, realistically. Calorie counting the MFP way, as NEAT+exercise, helps people avoid that 2nd pitfall, as compared with using a TDEE method.

Now, no one should be freaking out because I said all of these estimates are fraught with errors. In a literal sense, they are error-prone.

But as a practical matter, some tend to err on the high side, others on the low side, plus most are numerically minor in the big picture. We have so many estimates and observations in the mix that errors tend to cancel each other out. It all works well enough to be practical and successful. Trying to be as accurate as possible is still a helpful strategy. (If you were going on vacation with a map that didn't include all the sideroads, you wouldn't just drive willy-nilly cross country. You'd drive based on what you did know, not freak out about what you didn't, right?)

Ooooh thank you for this!!! Those are some amazing analogies that really do help and I appreciate the advice so much!! I don’t think it’s a bad idea to try to eat back a portion of exercise calories and reevaluate in a couple of weeks so I’ll definitely do that and take it on board!

nurabh94 wrote: »

TeaBea wrote: »

yirara wrote: »

Wait! Does MFP refuse to safe if you eat 1200 calories and log a workout of say 300 calories and don't eat it back? I thought it only did this for just under eating. I'm certain I might have done that a few times in the past without problems. TO, how many calories are you consuming each day?

But this is under eating. 1200 less 300 = 900. Do you think 900 calories is reasonable?

My Fitness Pal gave you 1200 calories based on your activity level before exercise (and your weekly weight loss goal). The reason exercise is added back is because it was not in the original calculation.

There's a video link in this thread: https://community.myfitnesspal.com/en/discussion/818082/exercise-calories-again-wtf/p1

I’ve never thought Of it like that!!! 900 sounds low!!