The Skinny on Body Fat Testing

Have you ever wondered about the best way to determine your body fat? Maybe you have measured your body fat using one method and then used a different method and got two completely separate results.

There are several methods of testing body fat...some more accurate than others. But before we explain the different types of measuring body fat, It would first be appropriate to explain a couple types of fat we all carry on our bodies.

The first type of body fat is essential fat and without it you would not survive. Essential fat is fat that your body needs to protect your organs. It lines the organs, acting as a cushion for vital tissue. In addition, essential fat is stored in your bone marrow and heart, lungs, spleen, intestines, liver, and kidneys. A proper range of essential fat for a man is between three and seven percent while a woman will need between eight and 15 percent of total body weight. This amount should be confused with overall body fat percentages.

The next type of fat is stored fat and we can't seem to get rid of it fast enough. This is fat that is stored in our body's reserve and a certain amount is vital for appearance and health. When stored fat becomes too low, a person may takes on a yellowish skin tone and the complexion deteriorates. When it becomes too high we endanger our heart and other vital organs, not to mention ruining our appearance.

With that being said, let us explore various body fat testing measures so you can be on your way to reaching your ideal body fat percentage.

The most accurate method of testing body fat is the hydrostatic weight measurement, although currently there is a competitor call the Bod Pod, which is being touted now as more accurate but is still not widely used. A person undergoing hydrostatic body fat testing is submerged in water on a chair attached to a scale and asked to slowly let the air out of the lungs. The normal body weight is then compared to the submerged body weight to determine body density. Then the lung volume is either estimated or directly taken using a formula. Although this method is highly accurate, it is not very practical and is extremely expensive.

Another type of body fat testing is done through bioelectric impedance. Since fat has no water and muscle contains about 70% of water, an electrical impulse would be greater through lean body tissue than through fatty tissue. Bioelectrical impedance may be done by the placement of electrodes on the ankles and wrist. Other types of bioelectrical impedance devices may be scales, which send electrical impulses and handheld impedance devices. Bioelectrical impedance can be expensive unless you go with the cheaper handheld models, but are fast and easy.

The next body fat testing method to discuss is the Body Mass Index (BMI). This is based on height and weight compared to a chart. BMI is extremely inaccurate as is does not consider fat-free mass or lean body mass. You may have an athletic, muscular person who weighs a lot due to muscle being denser than fat, but the BMI scale may show this person as inaccurately being overweight or obese. BMI does not work on the young under 18 or elderly. It is additionally inaccurate for use with athletes, bodybuilders and pregnant or nursing women. The BMI should be used with other body fat measuring methods and not as a stand-alone method.

Yet another method is the skin fold or caliper measurements. Based on an assumption that half of your body fat lies just under the surface of the skin, calipers measure the thickness of skinfolds at determined sites. Some trainers use the 4-site method : biceps, triceps, subscapula (under scapula bone), and iliac crest. To measure using calipers, the skin must be pinched only ¼ of an inch inward from the fold. There are manual calipers and electric calipers. The skin fold method is inexpensive, reliable, and easily accessible.Unless a skilled tester is using it, however, it can give inaccurate results. Additionally, calipers cannot be used on the obese.

The final body fat measurement device is the tape measure. The neck, chest, abdomen, hip, thigh, calf, upper arm, and forearm are measured. Then the total amount in inches is compared to a chart based on age. Depending on age group, only specific body parts are used to calculate body fat. For example, on a woman between the age of 27 and 34, only the abdomen, thigh, and calf may be used. Constants are then entered into a formula such as the following:

Constant A + Constant B - Constant C

-18.4 = body fat percent

Constant A may be the abdomen, constant B the thigh, and constant C the calf. The tape measure, although inexpensive and easy to access, may be extremely unreliable and is generally thought of as obsolete as an effective body fat tester. It is not accurate on the athletic, underweight or children.

Now that you know ways of measuring body fat, you can be better prepare to receive an accurate, tested method to determine your body fat. Many trainers and athletes use three methods in conjunction with one another to determine the margin of error between each device. Either way, have your body fat tested at least every six months if not in a workout program and monthly to every three months if participating in a body fat reduction program.