Learn to Calculate BMR to measure your calorie needs

Learning to calculate BMR (basal metabolic rate) is an important step in finding out how many calories you should be consuming per day. Basal Metabolic Rate is the amount of energy that you expend per day at complete rest. It measure the energy used to sufficiently function vital organs, with no physical activity taking place. This is an important number to calculate, and when combined with your activity level is a good way to calculate the number of calories you need to maintain your weight. With this number you can proceed to calculate the caloric intake you need to achieve your weight goals.

There are a number of formulas to calculate BMR, with the most well known being the Harris-Benedict equations. It takes into account a few variables in its calculation- your height, age, and gender. There is criticism that since it takes into account overall body weight, it doesn't consider lean body mass and body fat. Other formulas include the Katch-McArdle and the Cunningham formula, the first of which measures RMR (Resting Metabolic Rate) which is closely related to BMR. These formulas may be more accurate as they take into account the composition of your body weight, namely lean body mass and body fat.

You do not have to be a mathematician or even need a calculator to measure BMR. For most of us, the easiest option is to find a website where you can enter your gender, age and height and let the website calculate BMR for you. Here are a few sites you can use to calculate BMR.

http://www.bmi-calculator.net/bmr-calculator

http://sallysymonds.com.au/resources/59-bmr-calculator

http://www.fitwatch.com/qkcalc/bmr.html

From here, to calculate your actual daily calorie needs, the BMR value is multiplied by another number which is based on your activity level. The value of this number ranges between 1.2 and 1.9. Most formulas calculate a sedentary lifestyle as 1.2, moderately active lifestyle as 1.55 and extra active lifestyle as 1.9.

Go here to find the number corresponding to your activity level.

So if you have calculated your BMR to be 1580, and you live a moderately active lifestyle, you would multiply 1580 x 1.55 = 2449 calories.

This is the daily number of calories you need to maintain your weight. So if you are looking to lose weight, you can use this number to calculate how many calories you you need. Similary if your goal is to gain weight, simply add on calories to this amount to find out how many calories you should be consuming to reach this goal. You can start with 100-250 calories, and combined with regular cardio vascular exercise, see if this brings results to your body weight. If you do not see results within a few weeks, add/subtract another 100-200 calories, and continue until you start to see results. Allow time for you new diet to have an effect, do not expect results over night. When combined with regular exercise this change in your caloric intake should have a positive effect in taking you closer to your weight goals.

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