exercise calories explained

I typed this up for another thread, but because if all the questions about exercise calories, I thought I'd post it separately.


*disclaimer*
Everything I'm about to say assumes no special dietary or health "conditions"
*/disclaimer*

Healthy weight loss comes from maintaining a healthy calorie deficit. A deficit that is too high can (and often will) result in a lower number on the scale, but there are several unhealthy side effects (loss of muscle/lean body mass being the most common). Maintaining a reasonable calorie deficit while eating correct macros will lead to healthy weight loss.

How you get to that calorie deficit is up to you. This is where the MFP diet profile comes into play.

The diet profile allows you to specify a number of things. The 2 we care about for this conversation are your activity level and your goal. How you set these will determine whether or not you should be eating back your exercise calories.

Activity Level
This is where you set your daily activity level. *Most* people set this to reflect their activity level NOT including exercise/workouts. As such, they track their exercise separately as part of their diary. MFP uses this (along with the rest of your profile data) to determine an estimate for required for daily calories - i.e. how many calories you need each day to maintain your body as it currently is.

Goal
This is where you set your weight gain/loss goal. MFP uses this to set a daily calorie goal to help you reach your weight goals - a calorie deficit if your goal is to lose weight, a calorie surplus if you want to gain.

So, with all that said... how do we know if we should be eating back exercise calories or not? Well, it comes down to how you setup your profile.

Assuming your goal is to lose weight, MFP will calculate a healthy calorie deficit for you based on age, weight, activity level, etc. That number is what you need to be NETTING each day. Period. There is no debate here. The concept of net calories is just like net income... I'm REALLY hoping that doesn't need to be explained.

So the need to eat back exercise calories really comes down to how you determined your activity level when setting up your dietary profile. If your set activity level does NOT account for exercise/workouts (this is how most people use MFP), then you should be logging your exercises separately and eating back those calories. Why? In order to hit the calorie goal MFP set for you based on your profile data/goals. Consider this example: Your daily calorie goal is 1500cal. That number is calculated by MFP based on your profile data and is the number of calories you need to net each day to hit your weight loss goal. So you eat 1500cal. Good. Then you workout and burn 350 calories. Your NET intake for the day is now 1150, which is too low, and thus you need to consume an additional 350 calories during the day to compensate for the workout and be able to hit your goal of 1500cal for the day.

Make sense?

Alternatively, if you set your activity level so that it DOES account for your daily exercise, then the daily calorie goal MFP sets for you takes into account those calories burned during exercise, and as such you do NOT need to eat back burned calories. Example: Your daily calorie goal is 1850 (higher because MFP is accounting for daily exercise). So you eat 1850 calories. Good. Now you exercise and burn 350 calories. MFP already accounted for those 350 calories to be burned because of the activity level you set in your profile, so MFP already knows you burned them. As such, there is no reason to log the exercise separately, and you don't need to eat back those calories.

I hope this clears up the whole exercise calorie question. If nothing else, it gives me a pre-typed response I can cut and paste into future exercise calorie threads.


A couple of side notes:
- a little common sense and some knowledge of YOUR body goes a long way
- hunger (or lack there of) is not always a good indicator of if/when you should be eating
- just because something works for you doesn't automatically make it good advice

Sorry if I am being dumb here but I still have a question about exercise and its results on calories.

I start with 1320 calories allowance.


Two possibilities:

1. I eat 1320 calories, but I exercise and save 320 calories - a net value of 1000.

2. I sit still all day and do no exercise. As a result I get by with 1000 calories.

In both cases, I save 320 calories. Surely the exercise option is better for me?


If I am expected to just eat more to make up any calories I save by exercising, what is the point of the exercise?


You seem to be saying I have to use up ALL of the allotted calories, including any I save from exercise.

It seems odd to be suggesting I can lose weight by eating more.

To lose weight you need to be in a healthy caloric deficit. There are 2 ways to accomplish that:

1) Set your daily caloric intake at a deficit
This is what most people do, and is how MFP is designed to work. You figure out your daily caloric need then set your calorie goal lower than that. For example.. if your daily caloric need is 1800, you might set your daily calorie goal to 1400. That puts you in a caloric deficit and you will start to lose weight*. When you exercise you burn additional calories. These burned calories are not accounted for in your daily need or the calorie goal you set based on that need. So exercising increases that caloric deficit. The thing to watch here is how big that deficit gets. Every body responds differently, but the larger the deficit the worse it is for your body (the assumption is that the larger the deficit gets the harder it is to properly fuel your body). And this is why people recommend eating back exercise calories.

2) Use exercise to create the deficit
With this method you set your daily caloric intake to equal your daily caloric need. Then you exercise and burn calories. Those burned calories are not accounted for when you set your daily goal equal to your daily need, and thus you end up in a deficit. The size of that deficit is dependent on your workouts. You burn 75cals walking the dog and your deficit is 75 cals. You burn 500 cals running and the deficit is 500.



*This is VERY simiplified and makes A LOT of assumptions, but is good enough for this conversation.



As with everything, there is some variance here. Every body resonds differently to diet, exercise, nutrition, etc. so there is some trial and error required to find your body's "sweet spot". Pick one of the above methods, do it for a couple of months and see what happens. Then you can make a couple of subtle changes here and there, do that for a month or two and see if you body responds better or worse. But always start with one of the above methods, then go from there.

One of the biggest problems I see is people mixing elements/strategies from different programs. They want to use MFP's calorie calculations with weight watcher's zero point foods combined with what they heard from their coworker's brother's personal trainer. It doesn't work that way. Unless you really understand the ins and outs of nutrition and exercise (and if you did we wouldn't be having this conversation), you need to pick ONE method and do it. Don't mix them up, don't do a little bit of this and a little bit of that. Pick one, commit to one.

Okay, another question. I skimmed the other posts and didn't see this one, sorry if I missed it. My treadmill says my calories burned was 128, but it does not take my weight or anything else into consideration. When I posted my exercise it said my calories burned was 232 but that I should go with what my machine said. Does the site factor in my lifestyle and weight? If so, I should use the site's calculations for calories, yes?

You kinda got passed by so I'll try to answer.

This depends on what your settings are set on. If you are set to a Sedentary lifestyle then you need to add in your exercise calories. If you are set at one of the higher levels then these levels take exercise into account and you don't need to add them.

As for your treadmill. I wouldn't trust anything that doesn't take your weight and age into factor. a 250 lb woman is going to burn more calories in 15 minutes than a 150 lb woman on the same settings. So personally I would go with what the site says and not your machine because you will be short changing yourself.

Sorry if I am being dumb here but I still have a question about exercise and its results on calories.

I start with 1320 calories allowance.


Two possibilities:

1. I eat 1320 calories, but I exercise and save 320 calories - a net value of 1000.

2. I sit still all day and do no exercise. As a result I get by with 1000 calories.

In both cases, I save 320 calories. Surely the exercise option is better for me?


If I am expected to just eat more to make up any calories I save by exercising, what is the point of the exercise?


You seem to be saying I have to use up ALL of the allotted calories, including any I save from exercise.

It seems odd to be suggesting I can lose weight by eating more.

That was my question too.
Anyone care to answer?

Lastly... when you say you wore your HRM for 24 hours? Is that a traditional HRM (polar, or the like)? Or are you talking about a bodymedia fit or something along those lines? Traditional HRMs use calculations to estimate calorie burn. One of the assumptions made by HRMs is an increase in oxygen exchange which happens during steady state cardio. As such, wearing an HRM during rest times will give a very inaccurate reading of actual calories burned.

Just FYI.