1

What's the relationship of calories burned (e.g. through exercise) and appetite level?

Let's say there are two hypothetical situations:

A) Over the course of one day my body burns 2300 calories but I only eat 1800 calories worth of food. Some of the calorie burn is from a mild amount of cardio.

B) I try to be more active and burn 2800 calories throughout the day but I eat 2300 calories worth of food.

Assuming the same balance of protein/carbs/fats/etc between both diets, do I feel more hungry in scenario A than B?

Perhaps another question in itself: will I lose the same amount of body fat in both scenarios?

3 Answers 3

2

First and foremost, I am not a dietician, so add 0.2 kcal for a grain of salt.

That being said, there's at least tow different kinds of hungry in my experience: one is the feeling of a physically pretty empty stomach, the other is a low level in the energy supply (blood sugar).

The former will decrease if you eat more (by volume, salad, water, and those puffed rice crackers are your friend here), regardless of calorie deficit. It should also be decreased by working on your abs, because they physically constrain the stomach.

The latter is decreased by getting more energy into your system, either by eating more, or by exercising your body to a point where it goes for the fat depots, which is easier if you are more active.

So basically, I think your deficit might be easier to do with more activity and more intake, both by volume and caloric value.

1

Assuming the balance of protein/carbs/fats are the same, the only thing left is the net between calories burned and calories consumed. But in your example they are the same. In theory the amount of fat loss and hunger levels will be the same.

In practice, there are so many variables that someone can't just give a blanket answer. For example, there is a minimum amount of Calories you need before the body goes into starvation mode. In starvation mode, the body tries desperately to hold on to the fat while it gladly sacrifices your muscles. Another example is someone who has trouble absorbing nutrients from certain foods. Even if the macro ratios are the same, that person may have diminishing returns on the food they eat--meaning that they have fewer usable calories in the second scenario.

The best thing to do is perform sane dietary experiments on yourself to see if it plays out for you. I would be able to give an answer for my body, but my experience may not apply to you and your circumstances.

1

Gary Taubes argues in his very highly acclaimed Why We Get Fat: And What To Do About It that exercise does not help weight loss, because you get hungrier proportionally to the intensity of the work out.

I am not sure if there are enough of studies on the topic, but Taubes works are heavily referenced, so I am inclined to trust this conclusion.

Keep in mind that for weight loss, the diet is many times more important than working out.

1
  • I just finished reading that book, thanks for the recommendation! I don't think Taubes argued that exercise doesn't help weight loss because it affects appetite, but because the body will adapt (long-run) to the energy requirements and because exercise doesn't affect the mechanism that burns fat for energy (but insulin does, and carbs affect insulin levels). But I think you're right (at least if Taubes is right) - diet is much more important than working out.
    – etoleb
    May 3, 2012 at 2:55

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.