Learn Your BMR - Not Your BMI

Do you know your BMR? I know mine, it was another strategy I used in my weight loss success! Ah, you are probably wondering what BMR is. Well, it simply is your Basal Metabolic Rate. In ordinary English, that is the amount of calories your cells need to stay alive. It is the absolute minimum energy your body burns, and does not include activities such as digestion, respiration, and circulation. Why is this important to know? If you do not know how many calories you burn each day it is hard plan an effective weight loss strategy. As I stated, BMR is strictly basal, it does not include bodily functions, nor does it include your daily activity level. While you can mess around with math, I have a web link that helps you make an estimation of your BMR. http://home.fuse.net/clymer/bmi/ This site uses the Harris-Benedict formula, which dates back to the 1920's and requires you to input gender, age, height, and weight. Though old, it still serves as a rough guide – it worked for me quite well. Once you calculate your BMR, you can use a multiplier based on your level of activity, and voila, you have an estimate of your daily caloric output. Here are the multipliers to use:

Sedentary = BMR X 1.2 (little or no exercise, desk job)

Lightly active = BMR X 1.375 (light exercise/sports 1-3 days/wk)

Moderately active = BMR X 1.55 (moderate exercise/sports 3-5 days/wk)

Very active = BMR X 1.725 (hard exercise/sports 6-7 days/wk)

Extra active = BMR X 1.9 (hard daily exercise/sports & physical job or 2X day training)

Using this number, you can plan how much calories you should eat. It is common advice that you should never consume fewer calories than your BMR. I decided this was not acceptable to me. Instead, I calculated my BMR for my target weight and planned my caloric input based on that value. As you begin to lose weight, your BMR will decrease. In my case, at 240 pounds, my BMR was 2193, and when I reached 160 pounds, my BMR dropped to 1686, a difference of 500 calories per day. If you wonder why you lost an amount of weight and then reached a plateau, perhaps the major reason is your BMR dropped enough that your current level of activity and caloric input are no longer sufficient to keep your weight declining. In that situation, you will need to adjust – most likely your activity level, indeed I recommend you adjust that rather than cutting your food intake.The Harris-Benedict formula was designed with the average person in mind, it will under estimate people with high body fat percentages and overestimate people with low body fat percentages. To be honest, since I was already low-balling my BMR, I did not seek BMR equations adjusted for obese people. However once my body fat percentage became low, I wanted an equation that would provide me with a more accurate estimate of my BMR. I stumbled across the Katch-McArdle formula. It uses only your lean mass and a single equation is suitable for both men and women. I did not find an online tool for this one, but it was effortless to put the formula in a spreadsheet in any case. You will need to know your lean mass and convert it to kilograms for this formula, the web link I provided will give you a very rough estimate to of your body fat percentage. From that you can calculate your lean mass, divided your lean mass by 2.2 to convert it into kilograms. Here is the formula:

BMR = 370 + (21.6 X lean mass in kg)

That's all there is to BMR. By tracking your BMR along with your weight, you will keep steady progress on your weight loss journey!