What is Your Basal Metabolic Rate (BMR)…and Why is it Important?

By Mark / a few months ago
Keep a close eye on your BMR to ensure you stay healthy.

You need to understand your Basal Metabolic Rate (BMR) in order to achieve optimal results in the gym. So what is it, and how can you measure it?

Basal Metabolic Rate

If you are looking to burn fat, your basal metabolic rate (BMR) is a useful metric that gives you information on the speed of your metabolism. This article will give a clear definition of the basal metabolic rate and tell you exactly why it is important to you.

What is your BMR

Your BMR tells you how many calories your body would burn in a day if you did absolutely nothing except lay in bed. This number tells how much energy you need to sustain your vital organs like your brain, kidney, liver, heart, lungs, skin, muscles and your nervous system.

It is estimated that up to 60 percent of the calories you consume each day are used just to sustain these vital organs.

Basal Metabolic Rate (BMR) is an essential fat monitoring tool.

Calculating Your BMR

Your basal metabolic rate can be calculated in three ways. The first and most accurate way of determining the speed of your metabolism is by visiting a trained expert. 

This professional will check to make sure certain conditions are present in order to get the most accurate reading of your BMR. The list of conditions is as follows:

  • you must be resting and your muscles must also be relaxed
  • there should be very little to no change in the temperature around you
  • stress levels should be low, and you must be awake.

If any of these conditions are present, a correct measurement of your BMR will be impossible.

Stress can cause metabolic variations of up to 40 percent and sleep depresses your BMR by as much as 10 percent. Once it has been assured that all these conditions are set in place, the expert will be able to take a carbon dioxide and oxygen test after you have slept for at least eight hours. 

You will also have to refrain from eating for a period of 12 hours. This may seem very time-consuming, but if you truly want to know your BMR, this is the way to get it tested.

You can also get an indication of your basal metabolic rateby using equations. One equation that has been used for over 100 years is the Harris-Benedict equation. 

One equation is used for men and a slightly different equation is used for women. The equation for men to determine their BMR is found this way:

(basal metabolic rate = 66 + 13.75 multiplied by your weight + 5.0 multiplied by your height – 6.76 multiplied by your age).

Women can find their basal metabolic rate this way:

(basal metabolic rate = 655 + 9.56 multiplied by weight + 1.85 multiplied by height – 4.68 multiplied by age).

Another equation that has been found to be more accurate than the Harris-Benedict equation is the Mifflin equation and this equation has been in use since 1990. Using the Mifflin equation, men need to use this calculation:

(5 + 10 multiplied by weight + 6.25 multiplied by height – 5 multiplied by age).

Women can find their BMR with this equation:

(-161 + 10 multiplied by weight + 6.25 multiplied by height – 5 multiplied by age).

The results obtained from either the Harris-Benedict or Mifflin equation will give you the minimum calories you need per day just to sustain life.

Importance of BMR

Knowing your BMR will help you figure out how many calories you need to lose, gain or stay at your current weight. If you are sedentary, you will need fewer calories than someone who exercises regularly. 

The daily caloric requirement for someone who is sedentary and someone who works out regularly can vary by as much as 1000 calories.

 This bit is information is vital because you don’t want to consume too many calories if you don’t lead an active lifestyle. And if you exercise regularly, you want to ensure that you take in enough calories to keep your body functioning well and to fuel your workout routines.

Another reason knowing your BMR is important is because as you age, your basal metabolic rate naturally declines. When you are in your twenties your BMR might be around 1800 calories per day, but when you reach your fifties it may decline to 1650. By regularly measuring your BMR, you will always have a tool that will help you control your weight.

Fat Monitoring Tool

Knowing how to calculate your BMR will help you monitor your fat levels more effectively. You will be able to use it to make sure you don’t over-eat or under-eat. You can get your metabolism measured professionally or use one of the two equations to figure it out on your own.

However you decide to get it measured, just make sure you measure it at least once a year so you can stay in control of your weight.

About the author


Hello, I'm Mark. I'm a bodybuilding champion and have been active in the industry for over 10 years. I created this website to provide fellow bodybuilders with useful information to help them achieve their dream physique.