# How do calories work?

I read that a Bodypump session consumes about 600 cal. On the other hand, a human consumes 1800 kcal in a day. This means that a Bodypump session is only 0.00033% of the total daily calorie consumption.

How is it possible?

If you were consuming 2250 kcal to get muscle and now you want to lose the fat, you will have to do a lot of hours of Bodypump for a long time to get your goal.

Is it clear what I am talking about? Both amounts of kcal are very far between them.

• fitness.stackexchange.com/questions/1272/… - and the average person is not going to take care to use the appropriate one of those 3 when discussing exercise or food. Commented Aug 10, 2022 at 13:08
• In the context of food energy, "cal" is often written, but it always actually means "kcal". So Bodypump are actually claiming that their sessions burn 600 kcal. Commented Aug 10, 2022 at 13:38

## 3 Answers

Bodypump workouts aren't the only thing you're doing all day right?

You walking around your home consumes calories.

You cleaning your house consumes calories.

You sitting on the computer typing out a question consumes calories.

You sleeping consumes calories.

A "calorie" is a unit of measurement for energy similar to how a "kilometer" is a unit of measurement for distance. In this case, it's the amount of energy that is required to raise 1 gram of water by 1 degree Celsius. Food, muscle, glycogen, and body fat hold calories. Moving and living uses calories. All of these are rated in "kilocalories" or "kcal" or sometimes with a big "C". When people mention a "calorie", it's almost always referring to a "kilocalorie". The Bodypump is actually claiming it burns 600 kilocalories which is 33% of the total 1800 kcal consumed (Bodypump is also probably greatly exaggerating the number just fyi).

The biggest consumption of calories for most people is the "Resting Metabolic Rate" which is the amount of calories you use to "just survive". Breathing, thinking, heart beating, and so on. The things your body needs to do in order to continue living.

The second biggest consumption is your NEAT or "Non-Exercise Activity Thermogenesis". These include activities that you do throughout the day. These include cleaning, typing, walking, talking, writing, shopping, and much, much more.

The third biggest consumption is exercise. As you have seen, it's not actually as much as you would think. Although it does help significantly.

The fourth biggest consumption is the Thermogenic Effect of Food which is how much energy it takes to digest the food you consume.

All four of these things combined make your Total Daily Energy Expenditure which is your TDEE. If you eat equivalent to your TDEE, then you will not gain or lose weight. If you eat above it, you will gain weight. If you eat below it, you will lose weight.

*Note: This distribution is different for everyone so don't think this is set in stone. It's just an example.

If you would like an estimate of what your BMR/RMR is, there are a variety of calculators on the web.

This website mentions three of the most popular ones: Mifflin-St Jeor Equation, Harris-Benedict Equation, and Katch-McArdle Formula. Each are described respectively as:

Mifflin-St Jeor Equation:

For men: `BMR = 10 x <weight_in_kg> + 6.25 x <height_in_cm> - 5 x <age> + 5`

For women: `BMR = 10 x <weight_in_kg> + 6.25H - 5A - 161`

Revised Harris-Benedict Equation:

For men: `BMR = 13.397 x <weight_in_kg> + 4.799H - 5.677A + 88.362`

For women: `BMR = 9.247 x <weight_in_kg> + 3.098H - 4.330A + 447.593`

Katch-McArdle Formula:

BMR = `370 + 21.6 x (1 - <bodyfat_percentage>) x <weight_in_kg>`

And then to estimate your TDEE, you'd multiply the BMR with a coefficient that depends on your activity level.

• Sedentary (little to no exercise): `TDEE = BMR x 1.2`
• Lightly active (light activity or sports 1-3 times a week): `TDEE = BMR x 1.35`
• Moderately active (moderate activity or sports 3-5 times a week): `TDEE = BMR x 1.5`
• Very active (high activity or sports 5-7 times a week): `TDEE = BMR x 1.7`
• Professional athlete (Physically demanding activity is your job): `TDEE = BMR x 1.9`

Though it should be stressed that these are estimates and your actual TDEE is going to be different.

• This answer is excellent, but could be greatly improved by providing some links to a few different RMR calculators. (They differ depending on which equation they use).
– JohnP
Commented Aug 10, 2022 at 14:02
• @JohnP I added some equations.
– DeeV
Commented Aug 10, 2022 at 14:35
• I appreciate that your graphic pegs the thermic effect of feeding at around 10%. I've seen wildly outrageous takes ranging from "the thermic effect of feeding is fake news" to "eating these certain foods is basically free because of the thermic effect of feeding". Commented Aug 10, 2022 at 14:40

Confusingly, in nutrition, the words “calorie” and “kilocalorie” mean the same thing. So if someone says that a Bodypump session burns 600 calories, that’s the same as saying that a Bodypump session burns 600 kcal.

So, if we assume that a Bodypump session burns 600 kcal, and a person eats 1,800 kcal a day, then that workout actually consumes 33% of their daily calories, not 0.033%.

• Slight clarification - For calories, there is a calorie, a Calorie (Upper case C) and a kilocalorie (1000 small c calories). A lower case c "calorie" is the single unit. It is the upper case c "Calorie" and kilocalorie that are equivalent.
– JohnP
Commented Aug 12, 2022 at 14:22

Calories are a unit of measurement for the energy content of food and beverages. When we consume more calories from food and drink than we burn off, our systems store the extra as body fat.

Checkout how many calories per day your body requires to maintain your weight.

Calorie Calculator