Understanding BMR
What is Basal Metabolic Rate?
Your Basal Metabolic Rate (BMR) is the number of calories your body needs to maintain basic physiological functions at complete rest, including breathing, circulation, cell production, and nutrient processing. It accounts for 60-75% of your total daily calorie expenditure.
Factors Affecting BMR
- Body Composition: Muscle burns more calories than fat
- Age: Metabolism slows with age
- Gender: Men typically have higher BMR
- Weight & Height: Larger bodies require more energy
- Genetics: Some inherit faster metabolism
BMR Formulas Compared
- Mifflin-St Jeor: Most accurate (90% precision)
- Harris-Benedict: Original 1919 equation
- Revised Harris-Benedict: 1984 update
- Katch-McArdle: Most accurate if body fat known
How to Use Your BMR
Your BMR is the foundation for calculating your Total Daily Energy Expenditure (TDEE). Multiply your BMR by an activity factor to estimate your daily calorie needs for weight maintenance, then adjust based on your goals:
- Weight Loss: Consume 250-500 kcal below TDEE
- Weight Maintenance: Match TDEE
- Weight Gain: Consume 250-500 kcal above TDEE