Fitness and nutrition: How to calculate daily calorie needs

Emeh Joy
By Emeh Joy

A calorie is a unit for measuring energy. To attain fitness, it is necessary to know how many calories the body needs by calculating the body's daily caloric intake.

How to calculate calorie need

Asides from exercise, nutrition is an essential aspect of bodybuilding and fitness. Unfortunately, many people do not understand their body's dietary requirements.

It is necessary to learn how to calculate calories as muscle building requires consuming an adequate number of calories daily.

This article offers a guide on how to calculate body calorie needs (also called maintenance calories). It also discusses macronutrients and how to calculate the number of calories to consume during the cutting or bulking phase.


Macronutrients are also called 'macros'. Macronutrients are generally the major nutrient types that provide the body with energy.

There are three macronutrients, namely- proteins, fats and carbohydrates. To keep fit, your dietary constituents should comprise these three macronutrients in the right quantity.

Your caloric intake should comprise foods from the three macronutrients. A study review recommended that people consume the macronutrients in the following percentages:

  • 15-20% of calories from fat
  • 25-30% of calories from protein
  • 55-60% of calories from carbohydrates

Other classes of food (vitamins and minerals) do not provide calories. But, each of the three macronutrients provides the body with calories.


Calories are the measure of amount of energy the body gives off after catabolism

There is the misconception that calories are bad. Calories are not bad because your body needs them for energy. However, it becomes bad when you eat too many calories without burning them off.

A calorie is a unit of energy. Calories are the amount of energy which your body release after the breakdown (digestion) of food. The higher the calories contained in a food, the greater the energy the food can provide to the body.

Every human activity (whether running, jumping or sitting on the couch) depends on the energy from calories.

If you eat excess calories than your body needs, the body stores the extra calories as fat. This means that even foods that are not fat can contain lots of calories. Excess calories, irrespective of the class of food, can be stored as fat.

The number of calorie in each of the macronutrients vary. A gram of carbohydrate provides four calories to the body. A gram of protein provides four calories to the body, while a gram of fat provides nine calories.

Understanding what a calorie is and calculating calorie needs will help you make better decisions with food consumption.

Bulking and cutting phase

Weight maintenance requires not consuming too much or too little of calories. It means consuming weight maintenance calories.

For people into bodybuilding, the body has to go through two phases called the 'cutting phase' and the 'bulking phase'.

The cutting phase involves cutting out excess fat. This phase is crucial, particularly for overweight people. In the cutting phase, you are expected to consume fewer calories.

The bulking phase is the opposite of the cutting phase. It is also an important phase for every bodybuilder because this is when you build the needed lean muscle mass. In this phase, you consume more calories than the cutting phase.

Bulking and cutting are bodybuilding phases (Photo by Tim Samuel from Pexels)

The mistake some people make with the bulking phase is that they don't bulk right. The fact that you are to increase your calorie intake this period doesn't mean you eat every type of food in sight. Every bodybuilder must find out the best foods for bodybuilding and stick with them.

Remember that eating unhealthy foods ruins the fitness journey and causes the accumulation of excess fat, which the body does not need.

How to calculate your body's daily calorie need

Body calorie need is also called 'maintenance calorie'. Body calorie needs mean the number of calories the body needs to maintain its weight. It is the number of calories the body needs to perform daily physical activities and basic metabolic functions.

One easy way to determine how many calories the body needs is to use simple calculations. You either do a simple calculation, or you use an online calorie calculator.

Whether you are calculating yourself or using a calorie calculator, you will need to weigh yourself first. This is because body weight will be required to calculate the body's caloric need.

Below is how to calculate body caloric needs, so you don't eat too many calories.

Step 1: Find your weight in kilograms. If your weight is in pounds, convert it to Kg by dividing it by 2.2 (1Kg equals 2.2 pounds).

Step 2: For men, multiply the weight by 1.0. For women, multiply by 0.9 (This shows gender is considered when calculating body caloric needs).

Step 3: Multiply by 24

Step 4: Again, multiply everything by your lean factor, as shown in the table below (there is a table for males and another for females). This will give you your basal metabolic rate.

Basal metabolic rate (BMR) is the number of calories your body will burn daily, assuming you lay on your bed doing nothing throughout the day. The basal metabolic rate is important for calculating the number of calories the body needs every day.

Lean factor multiplier table for males

Body fat percentage

Lean factor multiplier







over 28


Lean factor multiplier table for females

Body fat percentage

Lean factor multiplier







Over 38


(You can use an online calculator to find out your body fat percentage. Your fitness trainer can also help you do that).

Example: Calculating daily calorie needs

If you are a female with a bodyweight of 65kg and a body fat percentage that falls between 19kg to 28kg, you calculate your BMR first in this way:

65 * 0.9(female) * 24 * 0.95 (the lean factor multiplier for your body fat percentage)


1,334 is the number of calories your body would burn, assuming you were to lie on your couch all day doing nothing.

The next step after finding your BMR is to calculate your caloric need. This is where you will need an activity modifier (a measure of your level of activeness).

Step 5: Multiply your BMR by your activity level multiplier (as shown in the table below)

Activity level multiplier table

Activity level multiplier

Level of activeness


Very light activity e.g., sitting, light walk, studying, typical office job that requires sitting


Light activity, e.g., a job that requires standing such as laboratory job and teaching


Moderate activity e.g., jobs that require moderate physical activeness such as biking, landscaping and cleaning


Heavy activity e.g., heavy manual jobs such as athletics, engine manipulation and construction (Hard physical activity for about 4 hour per day


Very heavy activity e.g., moderate to hard physical activity for up to 7/8 hours per day

With this, you can easily calculate your body calorie need. For instance, if your activity modifier falls within the moderate range, your activity level multiplier is 1.65.

This means you multiply your BMR by 1.65

i.e. 1,334 * 1.65 = 2,201

Thus, your body needs you to consume 2,201 calories daily to maintain weight ( weight maintenance calorie). However, you might want to adjust your caloric intake depending on whether you want to gain weight or lose weight.

If you want to lose weight, you have to consume fewer calories than your body burns every day (about 400 fewer calories). On the other hand, if you want to gain weight, you have to consume more calories than your body burns daily (about 400 more calories).

Also, note that you can calculate body calorie need easily using an online calculator. It will help to know how many calories the body needs daily, as this will help you adjust your dietary habits.

How to calculate caloric intake during the bulking and cutting phase

If your weight is consistently the same (no loss or decrease), it means you consume the right amount of weight maintenance calories. However, if your weight reduces, you are experiencing a calorie deficit. This means you need to increase your calorie intake.

For the bulking phase, it is recommended that you increase your daily calorie consumption by 15 per cent, while for the cutting phase, you reduce your daily caloric consumption by 15 per cent.

This means if your daily maintenance calorie is 2,201 (as we calculated earlier), you should eat 1,870.9 calories daily during the cutting phase.

Here is how to calculate that:

First, get 15% of 2,201. i.e. 2,201 * (15/100)

= 2,201 * 0.15 = 330.15

Go ahead and subtract 330.15 from 2,201

2201 - 330.15 = 1,870.9

Thus, if you are in your cutting phase (you want to shed some fat), you should consume 1,870.9 calories. This is about 300-400 calories less than your maintenance calorie.

Also, for the bulking phase, you calculate the number of calories you should consume in just like the cutting phase, except, in this case, you are increasing by 15 per cent.

Since you already found 15 per cent of 2,201 to be 330.15. You add 330.15 to 2,201 to get the number of calories you should consume in your bulking phase.

2,201 + 330.15 = 2531.15

Calculating caloric intake for the cutting and bulking phase is important, especially for bodybuilders and fitness enthusiasts.