High School Algebra Finally Pays Off: The Body Fat Equation


When approaching your goals for a better you, every game plan needs to start with determining where you are, and where you want to end up. We're going to talk about some ways to assess where you are -- right now -- so that you can make sure that the goals you have set (or will set) are reasonable. And yes, this will be on the test!

Whenever going into battle, a commander will send out reconnaissance experts to collect information on the size and strength of the enemy. We will continue to use a "battle" theme in this article, because your fight to lose weight and lose fat is nothing short of that.

Just as the commander needs to have a good assessment of what he or she is facing, we need to have an accurate assessment of our current situation so that we can set proper and appropriate goals. An inappropriate goal can insure failure, or worse, cause us physical harm.

If your goal is to look like a swimsuit model in time for your Hawaiian vacation a month and a half from now, you'd better not need to lose more than a few pounds. If your goal is to lose ten pounds per week for the next six weeks, you're simply not being practical.

With that said, what is 'reasonable'? You probably know how much you weigh, but do you know what percentage of your overall weight is fat?

The best way to know is to see a doctor or go to a gym that can calculate your body fat percentage. Normal body fat levels for women are between 22 - 25% and between 15 - 18% for men. Lean people will be slightly less, and athletes even lower. In lieu of that, there is a simple calculation that serves as a good guide, but is no where near as accurate.

This method is called the BMI or Body Mass Index and was created by the National Institutes of Health in 1998. The BMI uses your height and your weight to generate a factor that suggests whether you are underweight, normal, overweight or obese.

The BMI is generalized, so it cannot take frame size into account. If you have a large frame, your BMI will seem worse than it is, if you have a small frame, your BMI will seem better than it is. Use it as a guide and then add a portion of common sense.

In order to calculate your BMI, use the following equation:

BW = Body Weight in Pounds
HI = Height in Inches

(BW / (HI * HI) ) * 703

You will need a calculator to solve this equation.

If you failed algebra, here is the equation in English:

Divide your body weight in pounds (BW) by the square* of your height in inches (HI) and multiply that result by 703.

Once you've calculated your BMI, use the following guidelines to find out how you measure up:

BMI < 18.5 You Are Underweight (you need to find a new article to read!)
BMI > 18.5 AND < 24.9 You are in the "Recommended Weight" zone!
BMI > 24.9 AND < 30 You are in the "Overweight" zone!
BMI > 30 You are in the "Obese" zone.

Again, this gives you a rough guide, but it also gives you (possibly) a more realistic view of your current situation.

This more realistic idea will help you to set more realistic and achievable goals, which lead to a greater degree of success!

( * - The "SQUARE" of a number means the number times itself. The "square" of 4 is 16.)

Michael Callen is the author of the Weekly Weightloss Tips Newsletter (ccwebgroup.com/tips) and the Chief Technology Officer for WellnessPartners.com, an online retailer of dozens of health and wellness products such as conjugated linoleic acid (CLA), r+ alpha lipoic acid (R+ ALA), and Green Tea Extract.

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