The Basal Metabolic Rate (BMR) is the minimum amount of energy (calories) the body needs to maintain vital functions at rest, such as breathing, blood circulation, temperature regulation, and internal organ function. Knowing your BMR is useful for planning diets and setting weight loss or gain goals.
Why learn about the BMR?
Knowing your BMR provides a clear idea of your daily calorie needs. This value represents the minimum energy consumed by your body at rest. Based on this figure, you can adjust your total calorie intake by multiplying your BMR by an activity factor that takes into account your daily exercise and movement levels. This allows you to design a dietary plan that promotes weight maintenance, loss, or gain, depending on your personal goals.
Main Formulas for Calculating BMR
There are several formulas for estimating BMR, the most commonly used being the following:
Mifflin-St Jeor Formula
This formula is considered one of the most accurate for calculating BMR in the general population:
- Men:
BMR = (10 × weight in kg) + (6.25 × height in cm) – (5 × age in years) + 5 - Women:
BMR = (10 × weight in kg) + (6.25 × height in cm) – (5 × age in years) – 161
Harris-Benedict formula
This formula, which was developed several decades ago, is also commonly used:
- Men:
BMR = 66.47 + (13.75 × weight in kg) + (5.003 × height in cm) – (6.755 × age in years) - Women:
BMR = 655.1 + (9.563 × weight in kg) + (1.850 × height in cm) – (4.676 × age in years)
It's important to remember that these calculations are estimates and the resulting values may vary depending on each individual's physical condition and body composition. For a more accurate calculation, a consultation with a nutrition professional is recommended.
How to Use BMR in Your Nutritional Plan
Once you know your BMR, you can adjust your daily calorie intake according to your activity level:
- Sedentary Activity: Multiply the BMR by 1.2.
- Light Activity: Multiply the BMR by 1.375.
- Moderate Activity: Multiply the BMR by 1.55.
- High Activity: Multiply the BMR by 1.725.
- Very High Activity: Multiply the BMR by 1.9.
This total value will help you determine how many calories you should consume to maintain your current weight or to achieve your goals, whether that's losing fat or gaining muscle mass.
Conclusion
The Basal Metabolic Rate is a tool that helps you understand your body's energy expenditure. Knowing your BMR allows you to adjust your diet and physical activity more precisely, making it easier to achieve your health and wellness goals. Although the formulas provide a good approximation, it's ideal to complement these calculations with the advice from a nutrition professional.