How To Calculate Your Calories

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Here is a 3 step guide to help you calculate your calorie targets for your goals.

There are a lot of different calorie calculators and formulas out there that you can use (Mifflin-St Jeor, Harris Benedict, Schofield, Cunningham, etc) and they are all predictions that spit out roughly the same answer. You can use height, age, weight, lean body mass, activity level and more in different types of equations.

The one we are using here is a very simple one known as the Mac MET BMR Method and all you need is your current weight, an idea of your activity level and your goal in mind (and a calculator).

Remember though, it is just a starting point! 

If you are looking for something more specific or athletic performance is important to you, send us an email and we can discuss it further with you.

Step 1: Estimate the energy needed to function at rest.

In Step 1 we estimate how many Calories your body requires to keep up it’s vital internal function.

This is known as BMR or Basal Metabolic Rate. 

How to:

Males: Multiply BW (kg’s) x 24

Females: Multiply BW (kg’s) by 22

Example: Male 75kg. =75 x 24 = 1800 Calories

Step 2: Apply an activity factor to estimate weight maintenance Calories.

In Step 2 we add movement and activity to estimate the amount of Calories we need to maintain your current body weight.

Choose an activity factor that feels most appropriate. Remember this is just a starting point. 

How to:

Answer from Step 1 multiplied by selected activity factor.

1.1 (Sedentary) = Little or no activity, desk job

1.3 (Lightly Active) = Light activity, some of the day standing or walking

1.5 (Moderately Active) = Moderate activity levels, on feet most of the day

1.7+ (Very Active) = Hard daily activity or exercise eg. working long days on building site

Example: Male 75kg, with moderately active lifestyle. 

1800 x 1.5 = 2700 kcals

Step 3: Manipulate energy balance for goal. 

Step 3 involves applying a Calorie deficit for weight loss or a Calorie surplus for weight gain.

Weight loss: Reduce total Calories by 10-20% below estimated weight maintenance Calories. 

How to calculate a Calories deficit for weight loss:

Answer from Step 2 multiplied by 0.9 (10% Calorie deficit) or 0.8 (20% Calorie deficit)

Example (Weight Loss):

2700 x 0.9 = 2430 Calories

2450 rounded to the nearest 50 Calories.  

Muscle / Weight gain: Increase Calories by 10% over estimated weight maintenance Calories. 

How to calculate a Calorie surplus for weight / muscle gain:

Answer from step 2 multiplied by 1.1 (10% Calorie surplus). 

Only a small Calorie surplus is needed to maximise muscle growth results. 

Any larger and the proportion of fat to muscle gain overtime is likely undesirable. 

For ‘lean muscle gain’ a slight surplus is great. 

Example (Weight/Muscle gain):

2700 x 1.1 = 2970 Calories. 

2950 rounded to the nearest 50 Calories.

Weight Maintenance: If your goal involves maintaining your current body weight and you’d like to focus on general healthy eating, Step 3 does not apply.

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