I approached the subject of calories recently with a client and the reaction I got boarded on tears. The problem being that the word calorie is bandied around so often that everyone has heard it, but the reality is how many of us really understand it? If you are guilty of quietly smiling and nodding through a calorie centered discussion in the hope that no one will ask your opinion, read on, below is a simple explanation.

Calories are a unit of measure used to gage the energy that our body uses for fuel. Our bodies are a furnace which burns calories all the time, even when we are sleeping. Calories power our bodies processes such as; breathing, digestion, movement and just about anything else you can think of.

Calories come from macronutrients found in the food and beverages which we consume. Macronutrients are; carbohydrate, protein and fats. There are many theories on what the ideal amount of calories per macronutrient is optimal, depending on the latest research or fad diet, finding a balance is the key.


Where to find it


Grains such as bread, cereal, rice, pasta, Vegetables and Fruits


Low fat dairy, Nuts, Seeds, Oils, Avocados, Olives, Fatty Fish


Meat, Poultry, Fish, Cheese, Milk, Nuts and Legumes
The body uses calories from macronutrients differently i.e. calories from carbohydrate are used by the body primarily for energy, calories from protein are used for growth and tissue repair, and calories from fat are essential for cell, nerve tissue and  hormone production.

How many calories your body needs is determined by your BMR (Basal Metabolic Rate) x Activity Level.

If you consume more than your BMR x Activity then the result is weight loss, should you consume more than your BMR x Activity then it would stand to reason that your weight will increase.

Formula for calculating BMR

Women = 655 + (4.35 x weight (lbs)) + (4.7 x height (inches) – (4.7 x age (years)

Men = 66 + (6.23 x weight (lbs)) + (12.7 x height (inches) – (6.8 x age (years)

Formula for calculating your Activity Level

Sedentary = little to no exercise 1.2

Lightly Active = Light exercise on 1 – 3 days per week 1.375

Moderately Active = Moderate intensity exercise on 3 – 5 days per week 1.55

Very Active = High intensity exercise 6 -7 days of exercise per week 1.725

Extremely Active = A very physical job + high intensity exercise 7 days per week 1.9


Hopefully this sheds a little light on what a calorie is by definition.

For those of you who have reached for the calculator to tally up how many calories you should be consuming please remember that this is only a base figure, other factors may play a role in your ability to lose \ gain weight.

For further information contact your local GP, health advisor or fitness professional.


Happy Training,