How Is BMR Calculated?

Understanding BMR

Basal metabolic rate, or BMR, is the number of calories that your body normally burns while resting. It is the minimum amount of energy needed for your body to function.

Whether the body gains, maintains, or loses weight is based on the number of calories taken in compared to the number burned. BMR can be used as a baseline, helping to determine the amount of calorie change needed to have an effect.

Of course, everybody has a different metabolism. Some factors that affect the metabolic rate cannot be controlled, such as genetics and age. However, there are many actions that can be taken to help increase BMR and burn more calories.

Calculating BMR

The most common way that BMR is calculated is called the "Harris-Benedict formula." While not 100 percent accurate, it provides a good estimate that can be used for fitness planning.

For men, the formula is:
BMR = 66 + (6.23 x weight in lbs) + (12.7 x height in inches) - (6.8 x age in year)

For women, use:
BMR = 655 + (4.35 x weight in lbs) + (4.7 x height in inches) - (4.7 x age in years)

For example, a 72-inch tall, 30-year-old man weighing 180 pounds would have a BMR of 1916.73. In other words, his body would require a minimum of 1,916 calories a day.

Important Considerations

It is important to remember that the BMR number is only an estimate. Because this number is a minimum based on the body during rest, actual calorie requirements are usually higher in everyday life.

To estimate how many calories the body burns in a normal day, the BMR can be adjusted.

If you are only lightly active during the day, multiply the BMR by 1.375 to determine calories needed. Moderately active people should multiply by 1.55, and very active individuals by 1.725.

Once you have a good idea of how many calories your body requires during a typical day, you can adjust the actual intake in order to gain or lose weight. With practice and dedication, it won't be long before you see results and start achieving your fitness goals.

References

• BMR Basic Information
• BMR Calculator