What is Basal Metabolic Rate?
Another body composition scale reading that is often misunderstood is Basal Metabolic Rate (BMR).
Most people either don’t understand what this measurement means or confuse it with resting metabolic rate. We’re going to clear up the confusion.
What is Basal Metabolic Rate?
Even when you are doing nothing, your body has life-sustaining functions that need to be carried out to survive. This includes basic, essential functions such as breathing, digesting food, circulation, and more.
Basal Metabolic Rate (BMR) refers to the minimum number of calories required by your body to carry out these functions.
This means that even when you’re eating food, watching TV, sleeping or carrying out a desk job then you’re still burning calories!
What Is the Difference Between Basal Metabolic Rate and Resting Metabolic Rate?
Basal Metabolic Rate and Resting Metabolic Rate (RMR) are often used interchangeably and, while your resting metabolic rate should be an accurate estimate of your basal metabolic rate, they slightly differ.
As mentioned above, BMR calculates the number of calories you burn to cover your basal body functions. RMR, on the other hand, is the number of calories your body burns while resting.
How Do You Calculate Your Basal Metabolic Rate?
The easiest way to calculate your Basal Metabolic Rate is by using a body composition scale that provides this reading. This removes all guesswork and lets you use accurate up to date readings for your weight.
If you don’t have access to a body composition scale, there are a number of formulas that can be used to calculate your BMR.
Harris-Benedict Equation
Female
BMR = 447.593 + (9.247 x weight in kg) + (3.098 x height in cm) - (4.330 x age in years)
Male
BMR = 88.362 + (13.397 x weight in kg) + (4.799 x height in cm) - (5.677 x age in years)
Mifflin-St Jeor Equation
Female
BMR = (9.99 x weight in kg) + (6.25 x height in cm) – (4.92 x age in years) + 5
Male
BMR = (9.99 x weight in kg) + (6.25 x height in cm) – (4.92 x age in years) – 161
Cunningham Equation
BMR = 500 + (22 x lean body mass in kg)
This formula does require you knowing your lean body mass, however.
Basal Metabolic Rate Calculators
Alternatively use an online basal metabolic rate calculator, such as Active. This is simple and easy to use and does all the calculations for you.
What is the average Basal Metabolic Rate range?
For the average woman, a BMR tends to fall between 1,200-1,600 calories a day. The average man can expect a BMR between 1,600-2,000 calories a day.
How does Basal Metabolic Rate affect your diet?
The main benefit of knowing your BMR is because it can help you take control of your diet. Whether you’re looking to lose weight, maintain weight or gain weight, knowing how many calories you burn every day can make it easier.
Simply consume more calories if you’re looking to gain weight, equal calories if you want to maintain or less calories to lose weight.
However if you are trying to lose weight, it’s recommended to adjust your results using the Total Daily Energy Expenditure (TDEE) formula.
This is because your Basal Metabolic Rate is just the calories needed for your basal body functions. This doesn’t include walking, talking, exercising, etc. Therefore, if you just use your BMR figure, you may be consuming significantly less calories than you need to live, which can be dangerous.
What is the Total Daily Energy Expenditure formula?
The Total Daily Energy Expenditure (TDEE) formula, uses your basal metabolic rate, as well as your daily estimated energy level to work out your daily calorie consumption:
How Do You Increase Your Basal Metabolic Rate?
While Basal Metabolic Rate is calculated using a number of factors you can’t control, such as height, age and gender, there is one factor you can control - weight. Or, rather, your body's fat to muscle ratio.
Muscle mass burns more calories than fat.
In fact, it burns roughly 3 times the calories per pound per day. While fat burns around 2 calories per pound per day, muscle burns roughly 6 calories.
So, if you want to burn more calories, you should look into increasing your muscle mass. Then, even when you’re not working out, your body will be burning more calories.
Generally speaking, the best way to do this is by performing HIIT training or weight training. This will increase your lean muscle mass and also your BMR.
Further Reading
In addition to these individual blog posts, we’ve written a complete master guide to body composition scale measurements to help you truly understand what your readings mean.
If you’re wondering how often you should weigh yourself and when the best time to do it is, we’ve compiled all the relevant literature in this blog post.
What are the healthy body fat ranges and how can they be measured?