Question 1

What is the difference between BMR and TDEE?

Accepted Answer

Basal Metabolic Rate (BMR) is the energy expended at complete rest, without any activity. Total Daily Energy Expenditure (TDEE) includes BMR plus energy from physical activity, digestion (thermic effect of food), and thermogenesis. TDEE is generally 1.2 to 1.9 times your BMR depending on your activity level.

Question 2

Which BMR formula should I use?

Accepted Answer

Mifflin-St Jeor (1990) is considered the most accurate for most adults and is recommended by the American Dietetic Association. If you know your body fat percentage, Katch-McArdle may be more precise as it uses lean body mass. Harris-Benedict remains a classic reference but tends to slightly overestimate BMR.

Question 3

Does BMR change with endurance training?

Accepted Answer

Yes. Endurance athletes generally have a higher BMR than sedentary people because they have more muscle mass and a more active metabolism. However, prolonged intense training without adequate nutrition can paradoxically lower BMR (metabolic adaptation). This is why it's important not to create too large a caloric deficit.

Question 4

Why is BMR different between men and women?

Accepted Answer

Men have on average more muscle mass and less body fat than women. Since muscle is more metabolically active than fat, men generally have a 5-10% higher BMR at the same weight and height. This is why the Mifflin-St Jeor and Harris-Benedict formulas use different constants for each gender.

Question 5

How to use BMR for weight loss or gain?

Accepted Answer

For weight loss, create a deficit of 300-500 kcal/day below your TDEE (not below your BMR). For weight gain, add 300-500 kcal/day above TDEE. Never eat below your BMR as this slows metabolism and can cause muscle loss. For endurance athletes, too large a deficit impairs recovery and performance.

Basal Metabolic Rate (BMR) Calculator

Calculate your BMR

Frequently Asked Questions

What is the difference between BMR and TDEE?

Which BMR formula should I use?

Does BMR change with endurance training?

Why is BMR different between men and women?

How to use BMR for weight loss or gain?