How to Measure Body Fat: Body Fat Percentage Tests, Best and Most Accurate Ways to Measure Body Composition

How to Measure Body Fat

How to measure body composition: the most accurate techniques to evaluate body composition, body fat percentage testing.

The Methods

How to Measure Body Composition Test Methods

Regardless of how your body fat percentage is tested, there is no absolute way to determine your precise body composition.

The current body fat testing methods have evolved after years of research and are based on clinically significant relationships between at least one measurable or tested variable that correlates with body composition.

Costs and Accuracy

How to Measure Body Composition, Costs and Accuracy of Body Fat Percentage Tests

♥ There are a lot of variances in the equations that can be applied. For that reason, you should use an equation that makes the most sense for your lifestyle and situation.

♥ For example, if you are not an athlete, you should not use the same equation as they do for calculating body fat.

The following info will help you figure out which method is ideal for your specific needs.

Keep in mind that every testing procedure has advantages and disadvantages.

You will find the variety of ways to track your body fat percentage outlined below.

Pinch Test

How to Measure Body Composition With the Pinch Test, Anthropometry, Skinfold

Special calipers are used to measure folds of skin around specific spots on the body.

This is not a precise method; but it is relatively accurate if a training professional conducts the test.

Unfortunately, there are a variety of formulas and ratios that can be used to estimate body fat and quite often it is performed slightly differently by each person.

Thus, to increase accuracy, always have the same individual perform your pinch test.

♥ Also, always remember, the pinch test is not an exact measure of your real body fat percentage but can work wonderfully as a monthly reference to monitor your progress.

Accuracy: Moderately accurate when conducted by a trained professional.

Starting Cost: $10 to $20

Convenience: Widely available at health clubs and only takes a few minutes.

Body Fat Percentage Test Details: Using hand-held calipers that apply a specific pressure, the skinfold thickness is measured at several locations on your body.

♥ Your body fat percentage is then calculated using the sum of the measurements.

This method is used expecting that the thickness of fat just underneath the skin matches a constant measurement of total body fat, and that the areas selected for measurement exhibit the average thickness of fat underneath the skin.

These measurements are taken by holding the skin and underlying tissue and shaking it to leave out any muscle and pinching it with the calipers. Multiple readings should be made at each site to improve accuracy of the measurements.

♥ For the most part, skinfold measurements are very easy to do, inexpensive, and can be done anywhere.

♥ Overall, the results can be inconsistent as accuracy entirely depends on the skill of the person taking the measurements as well as the locations used for measurement.

♥ The calipers should be in good condition and be capable of maintaining sustained pressure.

♥ The more obese the individual, the more skillful the caliper operator will have to be due to the increased difficulty of pinching the skinfold correctly.

Bioelectrical Impedance, BIA

How to Measure Body Composition With Traditional Bioelectrical Impedance, BIA

A trained technician connects electrodes to your hand and foot while you lie down.

Then a harmless radio-frequency pulse is run directly through the body to measure water content.

♥ That number provides an estimate of body fat with an error of 2 or 2 1/2 percentage points.

However, exercise and different levels of liquid intake directly before the test can distort results.

Accuracy: Equal to the pinch test.

Starting Cost: $25.

Convenience: It takes only a few minutes and is found at some health facilities.

Body Fat Percentage Test Details: Impedance of the body is a measurement system that sends a harmless electric current through the body to assess body composition.

♥ It works because fat and muscle have different percentages of water.

♥ There is 70-75 percent water in muscle, while there is only 10-20% water in fat.

♥ Coupled with a person's height, weight, gender and age, body fat is calculated.

BIA has gained popularity because it's simple, cost-efficient, easy to replicate and non-invasive.

Hydration levels can also distort the accuracy of this test. For that reason, researchers are creating new ways to address fluctuations in subjects' different hydration ranges.

Multi-point placement of electrodes on different areas of the body, for example, has helped to improve measurement accuracy.

The BIA does have drawbacks.

♥ Results can be thrown off by hydration levels as the testing procedure assumes everyone is at normal levels.

♥ Inaccuracies arise when a person is dehydrated, and the test will overvalue body fat.

♥ For the best results, BIA should be conducted during the same time daily while you are properly hydrated.

♥ Try limiting any other variables that may change your hydration levels when you take the test first for the best results.

♥ Your goal should be consistency.

Bioelectrical Impedance, Bathroom Scale

How to Measure Body Composition With at Home With Bioelectrical Impedance, Bathroom Scale

Bioelectrical impedance analysis on a bathroom scale can be done from the privacy of your home in a minute or less.

♥ It's the most convenient and realistic procedure for most body comp trackers.

Many scale manufacturers now even include an optional bioelectrical impedance analysis, or BIA, upgrade on their machines.

You jump on a scale, wait for the numbers and presto, there is your determined body fat.

While standing, bioimpedance is conducted when your bare feet contact electrodes on top of the scale.

♥ First weight is measured followed by impedance.

♥ Most electric scales have pre-programmed settings to simplify the process.

♥ Gender, height, level of fitness and your weight are all used to establish your body fat.

♥ Obviously, hydration levels can still be an issue here.

♥ As stated above, try to limit those variables by keeping hydrated and weighing during the same time of the day.

♥ Consistency is the key.

Accuracy: Equal to the pinch test.

Starting Cost: $50, varies based on scale.

Convenience: It takes a minute or less and is usually at home.

Hydrodensitometry, Water Weighing

How to Measure Body Composition With Hydrodensitometry, Water Weighing

This is by far the most accurate body fat measurement method available.

The test requires you to exhale the air from your lungs as you get dunked into a pool of water.

♥ The method only has an error margin of 1 body fat percentage point.

Accuracy: The very best.

Starting Cost: $25 to $50.

Convenience: Accessible at many hospitals and various gyms, although it is exhausting and can last up to an hour.

Body Fat Percentage Test Details: This test requires weighing yourself outside the tank, then submerging yourself completely in the water and weighing again.

Since bone and muscle are denser in water, while fat is less dense, a person with more bone and muscle will weigh more in water than a person who has less bone and muscle, which means that the latter has a higher body density and a lower body fat percentage.

♥ The expectation with this method is that the density of fat mass and fat-free mass are consistent.

♥ However, this method may not be suitable for everyone. For example, because athletes are inclined to have a denser body mass than non-athletes, this may lead to a gross miscalculation of body fat percentage.

♥ In this way, the body fat of those with osteoporosis may also be miscalculated. Currently, there has not been any specific equation found to deal with these divergent groups.

♥ In attempting this method, it is necessary to consider the amount of air remaining in your lungs after exhaling, as the remaining lung volume can be measured, and it is beneficial to do so to get the best accuracy.

♥ Also, make sure the environment in which you're testing is completely still.

Despite this method being considered the best, many people find it to be difficult, while others are afraid of water, or cannot completely exhale. Clinical studies will often have subjects take the test several times, and the average be used for the results.

Bod Pod

How to Measure Body Composition With the Bod Pod, Air Displacement

You step into an egg-shaped chamber, sit for 20 seconds, and that's it.

♥ The chamber measures air displacement within your body.

This measurement is converted to your relative body fat after your weight is factored in.

Accuracy: Initial tests show that it's as good as immersion.

Starting Cost: $25 to $125.

Convenience: Found at only a few dozen hospitals and doctor's offices, but it's quick and easy. This method is limited by its high cost and limited availability.

Body Fat Percentage Test Details: Constructed on the same basic design as underwater weighing, the BOD POD uses sensors to determine how much air is shifted while an individual sits for 20 seconds in a capsule. It applies a calculation to decide body density, then predicts body fat.

Promising Calculation Methods

Dual-energy x-ray Absorptiometry

Dual Energy Xray Absorptiometry Body Fat Percentage Tests, DEXE

A new technology that is both accurate and decisive, DEXA, is established on a three-compartment model that breaks down the body into total body mineral, lean mass, and fat mass.

♥ This procedure is based on the belief that bone mineral content is directly comparable to the amount of photon energy absorbed by the bone being examined.

DEXA utilizes a whole-body scanner that has two low dose x-rays at multiple sources that read bone and lean mass at the same time.

♥ The sources are then mounted under a table with a detector overhead.

♥ The scanner passes across a person's body where data is acquired at intervals of 0.5 cm.

♥ A scan usually lasts between 10-20 minutes.

♥ It is a safe and non-invasive test for the individual, although they must lie completely still throughout the scan.

This test is quickly becoming the new best thing because it accommodates a much larger degree of accuracy in only one measurement and can show exactly where fat is spread out inside the body.

It is very dependable, safe, and poses almost no burden on the individual.

Though this test is not as precise in testing the extremely obese, and the cost of equipment is high, DEXA is rapidly moving from the lab setting into clinical studies.

Near infrared Interactance

Near-infrared Interactance Body Fat Percentage Tests, NIR

A fiber optic probe is attached to a digital interpreter that indirectly measures tissue makeup, fat, and water, at multiple locations on the body.

This method of testing is derived from studies that show optical densities are linearly applied to subcutaneous and total body fat.

The biceps are usually the location that is most often tested for estimating body fat using the NIR method.

The NIR light penetrates the tissues, bounces off the bone, and back to the detector.

The NIR data is then entered into an equation along with the person's height, weight, frame size, and level of exercise to predict their body fat percentage.

♥ This method has caught on with the public because it is simple, fast, non-invasive, and cost efficient.

Despite all this, the amount of pressure directed on the fiber optic probe during testing may affect the accuracy of measurements of the optical densities, with skin color and hydration levels being potential sources of error.

To this day, studies done with this method have had mixed results, with a high degree of error occurring with very lean and very obese individuals.

Many sources detail the importance of further research to confirm the effectiveness, accuracy, and suitability of this method.

Magnetic Resonance

Magnetic Resonance Body Fat Percentage Tests, MRI

 MRI is an x-ray-based method in which a magnetic field stimulates water and fat molecules in the body, creating a measurable signal.

♥ An individual lies completely still within the magnet as a computer scans the body.

♥ High-quality images show the volume of fat and where it is dispersed throughout the body.

An MRI takes around half an hour and is very safe since it doesn't use any ionizing radiation, but it is limited in its use due to the high cost of the equipment and testing.

Total Body Conductivity

Total Body Conductivity Body Fat Percentage Tests, TOBEC

This method of testing is established by lean tissue being able to conduct electricity better than fat.

♥ An individual lies in a chamber that creates a very weak electromagnetic field.

♥ The strength of the field relies upon the electrolytes that are found in the individual's body water.

♥ In around 10 seconds, TOBEC produces 10 conductivity readings that evaluate lean body mass.

Although this method is very accurate, its use is limited due to its high cost.

Computed Tomography

Computed Tomography Body Fat Percentage Tests, CT

Computed Tomography generates cross-sectional scans of the individual's body.

♥ An x-ray tube relays a beam to a detector.

♥ As the beam rotates around, the individual, data is compiled, saved, and applied to complex algorithms to create images that establish the composition of their body mass.

♥ CT is specifically useful in producing a ratio of intra-abdominal fat to extra-abdominal fat.

This method is non-invasive, but its potential is limited by exposure to radiation, and its high cost.

Help for You

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