
Calculate YOUR Total Daily Energy Expenditure
Once you know the amount of calories you need per day to maintain your current weight (your total daily energy expenditure), you can then be aware of the amount of food you can eat to maintain, lose or gain weight.
What is BMR?
Basal metabolic rate (BMR) is the amount of energy used while at complete rest. It is the minimum number of calories your body needs at rest to fuel its metabolic activity, for example to maintain bodily functions such as heart beat, breathing and temperature
What is TDEE?
TDEE is your Total Daily Energy Expenditure. Which is your BMR + any day to day activity. For example: Movement, walking, exercise
STEP ONE:
Calculate BMR (Basal Metabolic Rate) using the universal Harris–Benedict equation:
Women BMR = 655 + (9.6 X weight in kg) + (1.8 x height in cm) – (4.7 x age in years)
Men BMR = 66 + (13.7 X weight in kg) + (5 x height in cm) – (6.8 x age in years)
Work out the brackets first.
For example:
Female
Age: 28 years
Height: 171 cm
Weight: 62kg
Therefore,
BMR = 665 + (9.6 X 62) + (1.8 x 171) – (4.7 x 28)
BMR = 665 + 595.2 + 307.8 – 131.6
= 1436.4 calories/day
STEP TWO:
Calculate Total Daily Energy Expenditure (TDEE)
TDEE = BMR x Activity Factor
To determine your TDEE, determine your activity factor from the table below, and multiply this number by your BMR you just calculated above
Activity Factor Table
Amount of Exercise/Activity | Description | TDEE/ Maintenance |
Sedentary | Little or no Exercise/ desk job | TDEE = 1.2 x BMR |
Lightly active | Light exercise/ sports 1 – 3 days/ week | TDEE = 1.375 x BMR |
Moderately active | Moderate Exercise, sports 3 – 5 days/ week | TDEE = 1.55 x BMR |
Very active | Heavy Exercise/ sports 6 – 7 days/ week | TDEE = 1.725 x BMR |
Extremely active | Very heavy exercise/ physical job/ training 2 x/ day | TDEE = 1.9 x BMR |
Therefore,
TDEE = BMR x Activity Factor TDEE
= 1436.4 x 1.55
= 2226
This 28 year old woman needs roughly 2226 calories per day to maintain her current weight.
In Australia we use kilojoules (kJ) instead of calories to measure how much energy is in a food or drink, you would notice that kJ is what is seen in the nutrition panels. kJ are the same as Calories, just a different conversion:
1 Calorie = 4.2 kJs
So to work out how many kJ this woman needs would be:
2226 (calories) X 4.2
= 9349 kJ per day to maintain weight