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The Danger Of Overestimating The Calories You Burn

When you’re trying to lose weight, a big part of it is figuring out how to maintain the right energy deficit.

As I’ve discussed before, the amount of weight you will lose is determined by your energy balance.

This means if the amount of energy you take in is less than the amount you burn, you will lose weight.

Sounds pretty straightforward so far, right?

Well, in theory it is, but in real life it is not always so simple…

In fact, one of the biggest issues that I find many people running into here is accuracy.

That is, in order for all of this to work, you have to be able to accurately gauge the amount of energy that you’re taking in, as well as the amount of energy you’re burning – otherwise, the entire thing falls apart.

In this article, I’m going to cover one of the areas where this tends to go wrong, so that you can hopefully save yourself a lot of frustration.

The ‘Energy In’ Part

When I talk about ‘energy in’ here, what I’m really referring to is the number of calories that you’re eating each day.

Calories are simply a form of stored energy, and are really the only way that you take energy into your body.

In this respect, it makes this part of things a lot easier to figure out.

You can log what you eat in a food tracker like FatSecret or MyFitnessPal, and have a pretty good sense of how many calories you’re eating each day – and, by extension, how much energy you’re taking into your body.

Now I’m not saying that maintaining a diet is easy here – far from it – but what I am saying is that from a tracking standpoint, you can estimate this part of the energy equation fairly accurately.

The ‘Energy Out’ Part

Now let’s take a look at the other side of the equation – the ‘energy out’ part.

This is where things get a bit more tricky…

You see, unlike the ‘energy in’ part, where you can get a fairly accurate sense of things by tracking your food intake, the ‘energy out’ part has more factors to take into consideration.

First of all, your basel metabolic rate (known as your BMR, for short) makes up a major percentage of the total amount of energy your body burns each day.

This can vary significantly from person to person, and can be tough to quantify accurately.

After that, you have to take various other factors into consideration, such as the thermic cost of food, how much you’re exercising, and even how much you’re randomly moving around during the day (known as NEAT).

As a result, it is pretty tough to know how much energy you’re actually burning each day.

But without this vital piece of information, how are you supposed to know how many calories you should be eating in the first place?

Where Many People Go Wrong

As you might expect, there are many methods to determine how many calories you’re burning each day.

Unfortunately, many of these methods aren’t very accurate at all, and end up drastically overestimating your caloric expenditure.

One increasingly popular method is using a fitness tracker – like a FitBit or Misfit – to gauge how many calories you’re burning each day.

And while this seems good in theory, in my experience working with clients these trackers tend to significantly exaggerate expenditure.

This is because fitness trackers estimate calories based on the number of steps you’re taking each day, and then use an algorithm to determine how many calories you’ve burned based on that.

But as we’ve already discussed, with all of the factors that go into accurately figuring out how many calories your body is actually burning each day, these estimates are rarely on the mark.

What tends to happen, though, is that people who get into the whole fitness tracking thing start taking these caloric estimates far too literally.

That is, if their tracker told them that they burned 2800 calories that day, then they feel that eating anything under 2800 calories will cause them to lose weight.

And, in turn, they’ll be surprised (and unhappy) if they do that and don’t lose the expected amount of weight.

But this is the wrong way to go about it…

A Better Way to Estimate Your Calories

Instead of basing your caloric intake around the number that a fitness tracker gives you, I find that a better approach is to calculate your estimated energy expenditure yourself.

To do this, you first need to figure out your BMR, which I show you how to do in this article.

This varies considerably from person to person, but the specific calculator that I recommend using in the article tends to be reasonably accurate.

After that, you’ll want to calculate your TDEE, which stands for Total Daily Energy Expenditure.

Your TDEE will serve as a good basis for you to determine how many calories you should be eating each day.

If you’re planning on losing weight, I would recommend eating at 75-80% of your TDEE.

However, the most important thing to remember here is that your TDEE is still just an estimate of your energy expenditure each day.

A good estimate, but still just an estimate…

This means that you should view that number as a starting point, which you may need to adjust based on whether or not you’re losing the appropriate amount of weight each week when you weigh yourself.

But whatever you do, don’t treat ANY of these calculations as being absolute truths.

And if you do use a fitness tracker to gauge how many calories you’re burning, it is most useful to treat it as a relative measure – how much activity you did in a given day, compared to previous days.

That way, you’ll save yourself a lot of frustration, and be much less likely to fall into the common trap of overestimating the calories you burn each day.

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