A BMR Calculator for Men
What is BMR and why calculate it?
BMR, or basal metabolic rate, is the minimum energy required by your body in order to keep you alive. It is how many calories your body requires if you were laying in bed all bed doing nothing. This BMR calculator for men will calculate the average calories a male body at rest consumes. While BMR can be calculated for both men and women using different equations, my BMR calculator is focused on calculating BMR for men only.
Factors affecting BMR
BMR primarily depends on height, weight and age. BMR goes up as height and weight increase, and goes down as you get older. This means that with aging, losing weight or getting shorter (which tends to happen with age) you will need to either eat less or exercise more in order to maintain your body weight. BMR is more dependent upon height and weight for men than for women. In addition to these variables, another major factor that affects BMR in men is genetics. Some men just have a higher metabolic rate than others who are the same age, weight, and height. This genetic variance is the reason that any BMR calculator is at best an estimate of your true metabolic rate.
How to calculate BMR
To exactly determine your BMR, you would need to directly measure your energy expenditure over the course of a day with a calorimeter designed for humans. It sounds easy enough, but human calorimetry is in fact quite complicated. There are several methods, and all of them involve bulky equipment or being confined to one room for an entire day. Since few people have the time and money needed to set up a lab measurement, scientists have developed formulas to approximate your BMR with varying degrees of accuracy.
The BMR Equations for Men
Two of the most common formulas used to estimate BMR are Mifflin - St. Jeor and Harris-Benedict. They are easy to use because they only require you to know your weight, height, age, and gender - no special measurements needed! I'm still working on building a BMR calculator for men that does the math for you, so here are the mathematical formulas used so you can estimate it yourself .
Metric Harris-Benedict BMR calculation for men
BMR = (13.397 x weight in kg) + (4.799 x height in cm) - (5.677 x age in years) + 88.362
Imperial Harris-Benedict BMR calculation for men
BMR = (6.077 x weight in lb) + (12.189 x height in inches) - (5.677 x age in years) + 88.362
Drawbacks of using the formula
The Harris-Benedict BMR formula does not take into account the amount of fat and muscle in your body. Men with a higher percentage of body fat will tend to have a lower BMR, while very muscular men will have a higher BMR. Even so, this calculator provides a good estimate of your BMR and can be used to determine a starting point towards a healthy life.
Activity levels and BMR
Knowing your basal metabolic rate is just the starting point - basal means minimum, so unless you are in a coma, you burn more calories every day than your BMR would indicate. You can estimate how many calories you burn every day by using a BMR multiplier based on your activity level. For the Harris-Benedict equation, the multipliers are
- Sedentary - desk job, no exercise: BMR x 1.2
- Light exercise, 1-3 days per week: BMR x 1.375
- Moderate exercise, 3-5 days per week: BMR x 1.55
- Heavy exercise, 6-7 days per week: BMR x 1.725
- Very heavy exercise, twice a day (professional athlete level): BMR x 1.9
BMR calculator for men to lose weight
Even if you don't have access to a BMR calculating laboratory you can still estimate your BMR with this formula. This approximation is an important tool to keep your body fit and to maintain your weight. If you want to lose weight, just make sure you eat fewer calories than your body needs, as determined by your BMR and activity level.