What Is Basal Metabolic Rate Back

Even when resting, your body burns calories by performing basic functions to sustain life, such as:

breathing
circulation
nutrient processing
cell production

Basal metabolic rate is the number of calories your body needs to accomplish its most basic (basal) life-sustaining functions.

Basal metabolic rate vs. resting metabolic rate

Basal metabolic rate (BMR) is often used interchangeably with resting metabolic rate (RMR). While BMR is a minimum number of calories required for basic functions at rest, RMR — also called resting energy expenditure (REE) — is the number of calories that your body burns while it’s at rest.

Although BMR and RMR slightly differ from each other, your RMR should be an accurate estimate of your BMR.

How to estimate your BMR One popular way to estimate BMR is through the Harris-Benedict formula, which takes into account weight, height, age, and gender.

Women:

BMR = 655 + (9.6 × weight in kg) + (1.8 × height in cm) – (4.7 × age in years)

Men:

BMR = 66 + (13.7 × weight in kg) + (5 × height in cm) – (6.8 × age in years)

Why you might want to know your BMR

Your BMR can be used to help you gain, lose, or maintain your weight. By knowing how many calories you burn, you can know how many to consume. To put it simply:

Is your goal to maintain your weight? Consume the same number of calories that you burn.
Is your goal to gain weight? Consume more calories than you burn.
Is your goal to lose weight? Consume fewer calories than you burn.

How many calories you need everyday

If you’ve estimated your BMR using the Harris-Benedict formula, your next step is to include the number of calories you burn during daily activities based on your lifestyle:

Sedentary. If you get minimal or no exercise, multiply your BMR by 1.2.
Lightly active. If you exercise lightly one to three days a week, multiply your BMR by 1.375.
Moderately active. If you exercise moderately three to five days a week, multiply your BMR by 1.55.
Very active. If you engage in hard exercise six to seven days a week, multiply your BMR by 1.725.
Extra active. If you engage in very hard exercise six to seven days a week or have a physical job, multiply your BMR by 1.9.

The final number is approximately how many calories you need on a daily basis to maintain your weight.

Of course, this is an estimate. According to a 2007 studyTrusted Source, the formula would be more accurate if it included body composition, weight history, and other factors that have been shown to affect BMR.

How you can change your BMR

Your BMR is determined by a number of factors, including:

sex
weight
height
age
ethnicity
weight history
body composition
genetic factors

Of these factors, you can take steps to change your weight and body composition. So if you want to change your BMR, your first steps should be to lose weight and increase muscle.

A 2010 reviewTrusted Source indicated that resistance training can improve lean body mass composition and maintain fat mass reduction, increasing BMR.