DEXA body composition has been regarded as the gold standard measurement tool for its accurate and reliable results.

For those who are considering a weight loss journey or a customized fitness program, a DEXA scan provides an important baseline. Most are surprised with the motivation that real metrics provides to track progress and make changes for a healthier lifestyle.

FULL SAMPLE REPORT. So what does your personalized DEXA test report tell you? There are three possible ways that the DXA RMR result can be calculated. Jeor[2] or enter manually. A biometric study of basal metabolism in man. Washington, DC: Carnegie Institute of Washington, Carnegie Institute of Washington Publication You will then perform the DEXA right after, which will take an additional minutes for the test and review of results with our doctor.

If you have never had a scan, we recommend our clients to get the 2 scans so that you can have a before and after comparison to evaluate any programming you may be doing. The DEXA scan generally takes a total of 30 minutes to complete.

Again, this measurement is a non-invasive and quick method, with the advantage of not requiring exposure to radiation. BodPod has been shown to be a valid measure of group average body composition when compared to DEXA in female collegiate athletes However, research has suggested a difference of 5.

BodPod has also shown limited accuracy when attempting to determine changes over time 13 , a primary consideration when choosing an assessment method for athletes. Body density is determined and then used to estimate body fat percentage.

Again, this estimate is based on assumptions regarding the density of FFM, which may vary with age, gender, ethnicity and training status, potentially limiting its use in athletic populations Although this method was previously considered the gold standard by the American College of Sports Medicine, it is not without measurement error.

The results are highly reliant on subject performance, and as the process itself is uncomfortable, it may take multiple tests to get a valid measurement. For example, measurement error can occur through unsuccessful attempts to blow all of the air out of the lungs, or air bubbles trapped in hair or swimsuits.

Bioelectrical Impedance Analysis BIA BIA is based on the concept that electric current flows through the body at different rates depending on its composition It involves running a light electrical current through the body and determining body composition through the resistance of the tissues to the electrical current.

The low cost, speed of measurement and lack of need for technical expertise make BIA an attractive option for body composition measurement, particularly in epidemiological research. However, the accuracy of BIA is dependent on several factors, and as a result, it is likely the least valid measure of body composition discussed in this article.

BIA relies on empirical equations to estimate total body water, FFM and body cell mass; these equations use gender, age, weight, height and race as variables. Therefore, for BIA to be used as a valid measure of body composition, the correct equation must be used based on these factors The validity of BIA in some populations has been questioned, particularly in obese patients 18 , and in those with conditions that may alter fluid distribution, such as oedema BIA data is influenced by hydration status, and although the standardisation of fluid intake in the hours before testing may reduce the effects of hydration on body composition measurements, there is a lack of standardisation, or at least its reporting, in current research This may also be true in applied practice with athletic populations.

Exercise has been shown to lead to vast inaccuracies in body composition analysis using BIA 21 , as has changes in hydration status As a result, BIA may not be suitable for determining body composition changes due to fluctuations in hydration status following training.

Body composition measurement in vivo is an estimate. As mentioned previously, the cost and practicality of measuring body composition vary greatly, and often there is a trade-off between the two. Each method has a use in certain settings, and it is the job of the practitioner or user to understand the benefits and drawbacks of each method.

A further issue with body composition is often the focus of individuals on their absolute body fat percentage values. Rather than focusing on an absolute body fat number, it may be of more value to standardise measurement and track changes over time.

As measures of body composition are developed, more accurate measurements of FM and FFM can be established in various athletic populations.

This means that future research should aim to determine:. There are a multitude of body composition assessment tools available to the practitioner, each with varying cost, accessibility and accuracy in each population.

It is important to understand the benefits and limitations of each method, and how best to utilise each one in practice.

Most assessment tools are useful in various settings, and accuracy can be improved with proper standardisation prior to testing. Learn how to improve your athletes' agility. This free course also includes a practical coaching guide to help you design and deliver your own fun and engaging agility sessions.

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Body Composition Testing Changes in body composition can be determinants of successful performance, and there are several methods of body composition testing.

Contents of Article Summary What does body composition mean? What is body composition testing? How is body composition measured? Are there any issues with body composition testing? Is future research needed with body composition? Conclusion References About the Author. References C. Wells and M.

Pierson and S. Brito and G. Loucks, B. Kiens and H. Clarys, A. Martin and D. Renna, F. Conversano, E. Casciaro, M. For example, an abdominal skinfold improvement from 35mm to 24mm would show a significant improvement in that site even if the overall body fat percentage may have only reduced minimally.

BMI is often mistaken as measurable guide to body fat. However, BMI is simply a weight to height ratio. It is a tool for indicating weight status in adults and general health in large populations. BMI correlates mildly with body fat but when used in conjunction with a body fat measurement gives a very accurate presentation of your current weight status.

With that being said, an elevated BMI above 30 significantly increases your risk of developing long-term and disabling conditions such as hypertension, diabetes mellitus, gallstones, stroke, osteoarthritis, and some forms of cancer.

For adults over 20 years old, BMI typically falls into one of the above categories see table above. UC Davis Health School of Medicine Betty Irene Moore School of Nursing News Careers Giving. menu icon Menu. Sports Medicine. Enter search words search icon Search × Enter search words Body Composition UC Davis Sports Medicine UC Davis Health.

UC Davis Health Sports Medicine Learning Center Body Composition. Body composition. Fundamentals With respect to health and fitness, body composition is used to describe the percentages of fat, bone and muscle in human bodies.

Example analysis from a DXA scan PDF. Although body fat endures a negative reputation, fats and lipids play critical roles in the overall functioning of the body, such as in digestion and energy metabolism. Fat is the body's energy provider and energy reserve, which helps the body maintain a constant temperature.

Fats and lipids are also involved in the production and regulation of some hormones such as, steroid hormones. These are essential in regulating sexuality, reproduction, and development of the human sex organs, as well as in regulating the water balance in the body.

Fats and lipids also have important structural roles in maintaining nerve impulse transmission, memory storage, and tissue structure. Lipids are the major component of cell membranes. Fat serve as an energy reserve for the body, particularly as exercise progresses past 20 minutes.

From a performance stand point, excess body fat lowers your work to weight ratio, This means that a heavier person would consume more energy per minute of work resulting in a lower energy economy during activity. In addition, excess body fat can lead to additional loads placed on joint during weight bearing activities such as running, causing joint distress.

Healthy or athletic body fat percentages typically allow for more optimal performances, due to the improved economy and reduced injuries. The immune system is often impaired when body fat stores are too low.

A reduced ability to fight infections means more interruptions in training and more chance of being sick on race day.

For female athletes, there are some very immediate consequences of a low body fat level, including a fall in circulating oestrogen levels.

This in turn can lead to a loss of bone mass, causing problems for women in later life through an increased risk of bone fracture. Assessing body fat can be done using the following methodologies: Hydrostatic weighing, skinfold assessment and bio-electrical impedance. The scale can tell you how much you weigh, but body composition tells you where that weight is coming from aka fat, muscles, or bone.

Your body composition is also one of the best measurements of how physically fit you are and a predictor of increased risk for certain chronic diseases.

The higher your percentage of body fat, especially visceral fat that lines the organs in your abdomen, the greater your risk for developing nutrition-related chronic diseases such as metabolic syndrome, heart disease, obesity, and diabetes 1 , 2 , 3 , 4.

On the flip side, a higher lean body mass can often mean a better metabolism because muscle is more metabolic than fat and promotes a higher basal metabolic rate. A healthy body composition depends on your gender, age, and fitness level.

The "normal" range can also vary depending on the accuracy of the body composition assessment you choose. Generally speaking, you can use the following chart to assess your body composition status. Anything at or below average would be considered a healthy body fat percentage. There are five main body composition analysis tests on the market and each varies on the method and accuracy used.

Here are five ways to measure your body composition and learn your body fat percentage. Skinfold tests are one of the oldest and most basic ways to measure the amount of body fat you have.

Of course, because of the simplicity to this approach, it also tends to be the most inaccurate r , r. This method uses skinfold calipers to pinch the body in specific areas chest, thigh, and abdomen to measure the skinfold thickness.

This can be done through a 3-point measurement or 7-point measurement that expands the test to other body parts including the triceps, below the armpit Midaxillary , the shoulder blade subscapular , and hip suprailiac.

These measurements are then combined with a person's age and gender and input into a specific formula to provide a percent body fat estimate. Skinfold tests are limited because it only measures subcutaneous fat fat below the surface of the skin and does not do a full body assessment.

Not everyone stores fat in their body the exact same way. It is also subject to human error depending on who is performing the test.

Bioelectrical Impedance Analysis BIA uses a low electric current that travels through the body to estimate fat free mass. Since electricity can only travel through water, and each bodily tissue contains varying amounts of water, the flow of the electric current is impacted by the conductivity of each tissue type.

For example, muscle holds more water than fat, so the flow of the current becomes less interrupted low impedance when a person has more lean mass and more interrupted high impedance when they have more body fat. Because of the way these tools function, hydration status can significantly impact the accuracy of the results.

There are multiple types of BIA tools available on the market. Many are portable and extremely affordable, including bathroom scales and handheld machines. There are also more advanced BIA machines that use electrode placement on the body. Hydrostatic or underwater weighing is a form of densitometry that uses your body weight on land and in water, along with water displacement to estimate your body composition.

This method is based on Archimedes' principle, the buoyant force on a submerged object is equal to the weight of the fluid that is displaced by the object. Muscle does not weigh more than fat , but it is denser and takes up less volume per pound. In other words, muscle sinks and fat floats, so a person with more muscle mass will weigh more underwater than a person with a higher percentage body fat 7 , 8 , 9.

Please note: for clients under the age of 16, an Initial Nutrition Assessment must be completed before doing a body composition analysis.

If this applies to you, we encourage you to book a Discovery Call with one of our dietitians to discuss this more. Body composition analysis using bioelectrical impedance analysis BIA is not recommended in the following conditions:. This protocol will also be sent to you via our online client portal prior to your appointment.

Female clients: please ensure that your body composition analysis is booked at a time you are not menstruating as the retention of fluids can compromise the accuracy of the test.

Book a Discovery Call. Refrain from any caffeinated or alcoholic beverage.