# What Is BMI – BMR & How To Calculate It

If you are into fitness, you must have heard of these two terms for sure. BMI stands for Body Mass Index whereas BMR stands for Basal Metabolic Rate. People often get confused between these two terms because their abbreviation sounds somewhat similar but these two are very distinctive things. So I’ll try to break these two down in a very layman language so you all can understand what it actually means.

## Body Mass Index

BMI is simply a number derived from your height & weight. It is generally used to classify if a person is healthy or not, but sometimes BMI can be misleading because it doesn’t take a lot of other major factors into consideration which signifies if a person is healthy or not.

So, BMI = Weight (Kgs) / Height (M^2)

For example, a man is 1.8 m tall & weighs 80 Kgs. So his BMI would be 80/1.8^2 = 24.69.

There are certain ranges of BMI which signify how healthy a person is which are stated below.

Underweight = <18.5

Healthy         = 18.5-24.9

Overweight   = 25-29.9

Obese            = >30

## Basal Metabolic Rate

BMR is simply the number of calories your body needs to accomplish its most basic life-sustaining functions such as breathing, circulation, cell production & nutrient processing.

Your BMR is determined by a lot of factors:-

• Sex
• Height
• Weight
• Age
• Ethnicity
• Body Composition
• Genetic factors

### How to estimate your BMR?

A popular way to estimate your BMR is to use the Harris-Benedict formula which takes height, weight, age & gender into consideration.

For Women,

BMR = 655 + (9.6 * weight in Kgs) + (1.8 * height in cms) – (4.7 * age in years)

For Men,

BMR = 66 + (13.7 * weight in Kgs) + (5 * height in cms) – (6.8 * age in years)

The link below takes you directly to the page of the automated BMR calculator. Help Yourself if you don’t want to do all the mathematics above.

http://www.linear-software.com/bmr_bmi.html