How to Calculate Body Fat
Body fat scales claim to measure body fat quickly and conveniently. These body fat scales use the Bioelectrical Impedance method to measure your body fat percentage. A low-level electrical current is passed through your body and the "impedance", or opposition to the flow of current, is measured. The result is used in conjunction with your weight and other factors to determine your body fat percentage. Unfortunately, your body's "impedance level" can be altered by many factors besides body fat. For instance, the amount of water in your body, your skin temperature and recent physical activity can all adversely affect the results.So only by following strict rules can you hope to get an accurate measurement of your body fat using these scales. The most important rules to observe in order to make a more accurate calculation of your body fat are:
Measuring body fat with a set of body fat calipers is the most cost effective way to determine fat levels. But it's important to use them correctly. For instance, either have a professional take the measurements for you or buy a set of Accumeasure calipers (callipers) and follow the measuring instructions. Accumeasure are the only calipers than allow you to test yourself and most studies have shown that they are very accurate.
Hydrostatic weighing (underwater weighing) is the most accurate way to calculate body fat - that is, if you can find a hydrostatic weighing tank.
How does hydrostatic weighing calculate body fat? By using Archimedes Principle. Your examiner first calculates your body density by measuring the amount of water you displace when you immerse yourself in water. Then a formula is used to calculate body fat based on your body density. The problem is finding a facility (University, major gym or fitness center) which has a hydrostatic weighing tank!!
|Classification||Women (% Fat)||Men (% Fat)|
|Essential Fat||10-12 percent||2-4 percent|
|Athletes||14-20 percent||6-13 percent|
|Fitness||21-24 percent||14-17 percent|
|Acceptable||25-31 percent||18-25 percent|
Body fat is an important element in successful weight control. Body fat requires fewer calories than muscle. So the less fat/more muscle we have, the more calories we can eat before gaining weight. Body fat is often expressed as our "Body Fat Percentage" or "Body Fat Percent." Body fat percentage is the amount of body-fat-tissue as a percentage of total body weight. If your total body weight is 160 pounds and you have 32 pounds of fat, your body fat percentage is 20 percent.
The higher your percentage of fat above average levels, the higher your health risk for weight-related illness, like heart disease, high blood pressure, gallstones, type 2 diabetes, osteoarthritis, and certain cancers. Also, the higher your percentage of fat (and the smaller your percentage of muscle) the less calories you need to maintain your weight and therefore the easier it is to gain weight. This is because muscle is more metabolically active than fat tissue.
For a concise explanation of how ALL surplus calories (from fats, protein AND carbs) are converted to body fat and stored as adipose tissue, see How We Gain Body Fat?
ANNE COLLINS WEIGHT MANAGEMENT