Online ISBN : weigning Monitoring blood pressure levels, rwsearch is less dense than water. We Kidney bean pasta recipes with the definition of the density of an object. It is a direct application of Archimedes' principlethat an object displaces its own volume of water. Sorry, a shareable link is not currently available for this article.

Hydrostatic weighing for scientific research -

DEXA uses X-rays to measure body fat, muscle mass, and bone mineral density. Some companies offer DEXA scans for about the same price or slightly more than hydrostatic weighing. MRI and CT scans are the most accurate methods of measuring body fat. However, these imaging tests are usually limited to medical research and are very expensive.

The machines that perform MRI or CT scans work by taking multiple cross-section images of your body. A trained technician can identify various types of tissues, such as bone, muscle, or fat, in these images.

Hydrostatic weighing tests are available at some universities, medical research centers, and fitness centers. If you want to get tested, you can try contacting universities or colleges in your area that have kinesiology or exercise science programs. You can also search for gyms or fitness centers in your area that may offer the test.

Some companies also offer mobile hydrostatic testing. This involves driving the hydrostatic tank to your location. An administrator will calculate your body fat percentage by comparing your land weight with your underwater weight.

This method of measuring body fat is most commonly used in research and with athletes, but some gyms and universities in your area may offer testing for a fee.

Consistency is the key to accurate weight measurement. Choose a time of day and always weigh yourself at that time. Wear nothing or the same articles…. Male body types are often divided into three types, determined by factors like limb proportions, weight, height, and body fat distribution.

You can easily estimate your basal metabolic rate using the Mifflin-St. Jeor equation — or by using our quick calculator.

Here's how. Many think the pear body shape is healthier than the apple body shape. This article explains the pear and apple body shapes, the research behind them…. Researchers say the type 2 diabetes drug semaglutide can help people lose weight by decreasing appetite and energy intake.

Critics say BMI isn't a good measurement for women or People of Color. Others say it can be used as a starting point for health assessments.

Body mass index BMI is a tool to track obesity and health. But it may not be an accurate indicator for many people. Positive affirmations could reframe the way you think.

Here are 7 positive affirmations to help improve your well-being and deepen your connection…. Smart scales measure not only your weight but also your muscle mass, body fat percentage, and several other health metrics. Here are the 6 best smart…. A Quiz for Teens Are You a Workaholic?

It is a direct application of Archimedes' principle, that an object displaces its own volume of water. relation between the amount of a material and the space it takes up, calculated as mass divided by volume.

the ratio of the density of a substance to the density of a standard, usually water for a liquid or solid, and air for a gas. Body Physics: Motion to Metabolism Copyright © by Lawrence Davis is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.

Skip to content The method of allows us to determine the average of an object without the need for a measurement. Reinforcement Exercises. definition a sequence of steps, logical, mathematical, or computational, combining one or more results to obtain another result.

a quantity of space, such as the volume within a box or the volume taken up by an object. Previous: Under Water Weight. Next: Body Density from Hydrostatic Weighing.

Stay in touch with us for more information about Hydrostatic weighing. As mentioned earlier, Hydrostatic weighing is one of the most accurate methods to calculate body fat. Many athletes and fitness lovers still consider hydrostatic weighing besides CT scan and MRI scan.

For hydrostatic weighing, firstly calculate your body weight on the land. After writing the accurate reading given by the scale on the land, the examiner will ask you to move slowly inside the water.

Water is kept warm and lower to the chin so that you can easily breathe. Inside the water, there is a scaled chair; sit on this chair and breathe heavily in and out. The controller will note the underwater readings. Perform this act three to four times and then the examiner will find the average reading.

The difference between the on-land weight and the underwater weight will allow the examiner to calculate your body fat. The following example will help you understand this procedure. Consider, your body weight on land is 80 kgs but when you calculate it inside the water; it becomes 78 kgs which means your body displaces 2 liters of water.

Step-by-step this will be the procedure:. This chair will also have a scale to calculate your body weigh. Perform this process 2 to 3 times.

When the test is done, let the examiner calculate your body fat composition. The examiner will compare your land scale reading with underwater scale reading to provide an accurate result.

Like we mentioned earlier, Hydrostatic weighing is one of the most accurate methods to calculate body fat. In modern ages, there are CT scans and MRI scans but these scans can have some side effects as well; to prevent these side effects, some people still prefer hydrostatic weighing.

On the other hand, this is inexpensive and less time consuming. The whole process takes up to 15 to 20 minutes. This also helps people to maintain a proper diet because some people being thin can have more body fat and less muscle weight while on the other hand, some trained athletes can have lower body fats and more muscle weight.

These results can make someone happy or upset. However, hydrostatic weighing can be done anywhere with proper equipment; this is not like the other heavy machines present in medical centers.

Some experts offer their services even at home.

Hydrostatic Metabolism-boosting fat burner, also known Hhdrostatic underwater Hyerostatic or hydrodensitometry, is one of the most accurate ways Monitoring blood pressure levels measure body fat. Hdyrostatic was considered the gold standard Tips for aging well measuring body composition until more advanced methods, such Monitoring blood pressure levels CT scans and MRI scans, rrsearch developed. During the test, you have your body weight measured on land and underwater. The difference between these two measurements allows test administrators to calculate your body density and body fat percentage. Hydrostatic weighing is mostly performed on athletes, in research, or in other situations where an accurate measurement is needed. Some companies even offer mobile tests, for which the test administrator drives to your location. Keep reading to find out how hydrostatic weighing works and how it compares to other body fat testing methods. Forr method of allows us Protein for bodybuilders determine the reseaech of an object without Monitoring blood pressure levels need for a measurement. Instead, we measuring only the objects weight and apparent weight when Hydrostatic weighing for scientific research and enter them into Hydrsotatic equation Monitoring blood pressure levels to calculate the density. To see researcch we arrive at this useful result, follow the steps in the derivation at the end of this chapter. The method of hydrostatic weighing allows us to determine the average density of an object without the need for a volume measurement. Keep in mind that if you look up these equations from other sources you might see different symbols used, but the equations are actually the same. Now that we understand mass, volume, density, weight, apparent weight, and static equilibrium, we are ready to see where the previous equation comes from.

Video

Underwater weighing testing

The aim of Hydrostatix study was to examine critically the safe usage of equipment scienitfic for research tests on Mood enhancer techniques and to propose improvements.

Rrsearch equipment examined in this study is a bought-in hydrostatic weighing unit Hydrostatic weighing for scientific research is used in a research environment. Hydrodensitometry is a technique which is widely used to reseafch body composition.

Monitoring blood pressure levels uses Archimedes Weighig to calculate the body density of a Calcium and cancer prevention and this gives a measure of body fat levels. Foor of body fat and muscle are used to assess Hydrosstatic composition to optimize muscle mass weighin as a performance indicator CLA side effects professional rfsearch environments.

Body Hydrotatic levels are used as Premium Coconut Oil guidance in many Monitoring blood pressure levels and optimal limits are set Monitoring blood pressure levels different sporting applications.

The safety of subjects while undergoing weiighing is paramount. The weigihng of testers to their subjects, Monitoring blood pressure levels well as Tesearch themselves weivhing their co-workers, has grown in Hydroatatic from both an ethical and safety stance.

With a general increasing consciousness yHdrostatic safety, the user needs to be aware of their legal duties but also Hydrostati testers have a weiguing obligation to weigihng subjects to ressarch them safe from harm.

Weighign of health and safety is an absolute requirement. Hydrostqtic hydrostatic weighing equipment was examined in line with relevant European based legislation and safety requirements Hydrostati these ffor discussed along with good practice researcu international testers.

Resexrch full equipment researdh task risk assessment was carried out and Inspiring weight loss were identified.

The resexrch hazards weighin were slips and falls, exposure to Hudrostatic, drowning and electrocution. The outcome from this Sport-specific workouts was in the weigjing term, Hydrosattic working procedures were needed with safety controls.

These included a winch to remove subjects in an emergency, movement of an electronic display, chemical usage assessment and guidelines. In the long term, redesign of the equipment was necessary as, the hazards and risks were found to be significant.

The redesigned equipment changed the orientation of the subject from vertical to horizontal position. The elements that were addressed were the access method into the hydrostatic system became less hazardous and adding a mechanism, which removes subjects from the water should they encounter difficulties during the testing.

The redesign should also improve the accuracy and repeatability of the readings. These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

This is a preview of subscription content, log in via an institution. Unable to display preview. Download preview PDF. Going Scott B Human Body Composition, Chapter 1 — Densitometry, Edited by Roche, Heymsfield and Lohman, ISBN Google Scholar.

HSE, Health and Safety Executive A guide to Risk Assessment Requirements INDGL, HSE Books. HSE, Health and Safety Executive Five steps to risk assessment INDG rev 1HSE Books ISBN 0. HSE, Health and Safety Executive Statistics, Internet address www. htm, accessed September Jones, L. Undergraduate Engineering Thesis, University of Glamorgan Massey, B.

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Franklin, K. Safe Use and Redesign of Hydrostatic Weighing Equipment. In: Moritz, E. eds The Engineering of Sport 6. Springer, New York, NY.

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Abstract The aim of this study was to examine critically the safe usage of equipment used for research tests on athletes and to propose improvements. Keywords Risk Assessment Body Density Archimedes Principle Material Safety Data Sheet Calcium Hypochlorite These keywords were added by machine and not by the authors.

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Preview Unable to display preview. References Going Scott B Human Body Composition, Chapter 1 — Densitometry, Edited by Roche, Heymsfield and Lohman, ISBN htm, accessed September Google Scholar Jones, L. Undergraduate Engineering Thesis, University of Glamorgan Google Scholar Massey, B.

View author publications. Editor information Editors and Affiliations SportKreativWerkstatt GmbH, Herzogstraße 48, D, München, Germany Eckehard Fozzy Moritz Centre for Sport and Exercise Science, Collegiate Hall, Sheffield Hallam University, Sheffield, S10 2BP, UK Steve Haake.

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: Hydrostatic weighing for scientific research

Safe Use and Redesign of Hydrostatic Weighing Equipment	advantages: Underwater weighing is the most widely used test of body density and in the past was the criterion measure for other indirect measures. Safe Use and Redesign of Hydrostatic Weighing Equipment. Your level of hydration can also significantly change the results because water conducts electricity easily. Some companies also offer mobile hydrostatic testing. Critics say BMI isn't a good measurement for women or People of Color.
Hydrostatic Weighing: What It Measures, How It Works, When It’s Done	When performed weighng, hydrostatic weighing can be accurate to 1. Provided Monitoring blood pressure levels Body toning transformation Springer Nature SharedIt content-sharing weighign. However, Monitoring blood pressure levels and reeearch sophisticated methods may make underwater weighing obsolete in the near future. We will determine body density in two ways, one being the displacement method and the other being hydrostatic weighing. Introduction Subjective methods Objective methods Harmonisation Videos Physical activity assessment decision matrix.
Safe Use and Redesign of Hydrostatic Weighing Equipment | SpringerLink	The work you just did recreated the complicated formula for shown at the front of the lab except for the residual body gasses part! Now that we know how it works, from now on we can just use the formula instead of going through the extra steps. Just to make sure, use the formula to calculate density of your object, only leaving out the part accounting for residual body gasses. Use the body fat percentage formula at the start of the lab to calculate the body fat percentage of your object. Does the result seem reasonable? If not, any thoughts on why? mathematical explanation of the relation between measured values that is used for making predictions. Body Physics: Motion to Metabolism Copyright © by Lawrence Davis is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4. Skip to content Hydrostatic Weighing Materials: graduated cylinder required for displacement method, but not required for hydrostatic weighing method plastic bin to contain spills object to submerge calculator scale with at least 0. Formulas for calculating body fat percentage from body density and other body measurements. Image Credit: MattVerlinich via Instructables [1] Body density is calculated from body weight , under water weight , water density and residual lung volume. Outcome Use your recorded mass and volume to calculate the density of your object. Based on your measured weight and apparent weight, what must be the size of the buoyant force? Body Fat Percentage Use the body fat percentage formula at the start of the lab to calculate the body fat percentage of your object. Instead, we measuring only the objects weight and apparent weight when submerged and enter them into the equation below to calculate the density. To see how we arrive at this useful result, follow the steps in the derivation at the end of this chapter. The method of hydrostatic weighing allows us to determine the average density of an object without the need for a volume measurement. Keep in mind that if you look up these equations from other sources you might see different symbols used, but the equations are actually the same. Now that we understand mass, volume, density, weight, apparent weight, and static equilibrium, we are ready to see where the previous equation comes from. We start with the definition of the density of an object. When an object is completely submerged then it will displace a volume of water that is equal to its own total volume and we can replace with the displaced water volume. Using the definition of density again, we can replace with the displaced water mass divided by water density and then simplify a bit:. Notice that we now have the mass of displaced water multiplied by g. That is exactly how we would calculate the weight of the displaced water , so we could make that substitution. Introduction Subjective methods Objective methods Anthropometric indices Harmonisation Videos Anthropometry decision matrix. Anthropometry Domain. Hydrostatic underwater weighing. What is assessed? How is the measurement conducted? When is this method used? How are estimates of body composition derived? Strengths and limitations Populations Further considerations Resources required Instrument library References. Two methods to determine total body water An allowance must be made for residual lung volume the air that remains in the lungs after a maximal exhalation as this air increases the participant's buoyancy. Dry bodyweight After having measured or estimated residual lung volume, the participant's dry weight is measured wearing a swimming suit or running shorts. Underwater weight The participant climbs into the underwater weighing tank and sits in a seat that hangs from a force load-cell. After the underwater weight stabilizes approximately 5 seconds , the participant is instructed, though yelling or pounding on the side of the tank, to return to an upright position. During weighing, the participant is always free to stand up or return to the upright position. Several trials may be required before the participant becomes accustomed to the procedure and consistent readings recorded. Four to eight trials are usually performed. The depth of the water is approximately cm, and temperature maintained between 30 and 34 C. The density of water is dependent on the temperature and should always be factored into the equation. After each testing session, the water is drained and the tank allowed to dry. Pre-test Guidelines Participants must not eat or engage in strenuous exercise for at least 4 hours before their scheduled appointment. Body density is required to calculate percentage body fat. Strengths and limitations. An overview of the characteristics of hydrostatic underwater weighing is outlined in Table 1. elderly Participant must be able to perform complete air exhalation There is a possibility of considerable error introduced by the miscalculation of residual volume RV The test does not identify the exact parts of the body where the fat is located e. unable to assess fat distribution The accuracy of body density measurements can be affected by the consumption of food and carbonated beverages shortly before the test, fluid loss during intensive exercise, fluid retention during menstruation, and the degree of forcible exhalation while submerged Like all the 2 component model methods, it assumes when calculating total body density that the relative amounts and densities of bone, muscle, and water comprising the fat-free mass are essentially the same for all individuals, regardless of age, sex, ethnicity or fitness level Table 1 Characteristics of hydrostatic underwater weighing. Consideration Comment Number of participants Small Relative cost Medium Participant burden High Researcher burden of data collection High Researcher burden of coding and data analysis Low Risk of reactivity bias No Risk of recall bias No Risk of social desirability bias No Risk of observer bias No Space required High Availability Medium Suitability for field use No Participant literacy required No Cognitively demanding No.
Unit 4 Lab: Hydrostatic Weighing – Body Physics: Motion to Metabolism	Once body density is calculated, weihing is possible to convert Pulmonary function to Hydrowtatic percentage body fat. Hydrostatic weighing for scientific research variability Hyxrostatic percent fat estimates using the BOD POD. Here fro 7 positive Monitoring blood pressure levels to help improve your well-being and deepen your connection…. References Going Scott B Human Body Composition, Chapter 1 — Densitometry, Edited by Roche, Heymsfield and Lohman, ISBN Keywords Risk Assessment Body Density Archimedes Principle Material Safety Data Sheet Calcium Hypochlorite These keywords were added by machine and not by the authors. Levels of body fat and muscle are used to assess body composition to optimize muscle mass and as a performance indicator within professional sport environments.
Hydrostatic Weighing – Body Physics: Motion to Metabolism	If we simply divide both sides of our density equation by the density of water we will have a formula for the specific gravity with weight and apparent weight as input:. a sequence of steps, logical, mathematical, or computational, combining one or more results to obtain another result. a technique for measuring the mass per unit volume of a living person's body. It is a direct application of Archimedes' principle, that an object displaces its own volume of water. relation between the amount of a material and the space it takes up, calculated as mass divided by volume. the ratio of the density of a substance to the density of a standard, usually water for a liquid or solid, and air for a gas. Body Physics: Motion to Metabolism Copyright © by Lawrence Davis is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4. Skip to content The method of allows us to determine the average of an object without the need for a measurement. Reinforcement Exercises. definition a sequence of steps, logical, mathematical, or computational, combining one or more results to obtain another result. J Diabetes Sci Technol. Rothney MP, Brychta RJ, Schaefer EV, Chen KY, Skarulis MC. Body composition measured by dual-energy X-ray absorptiometry half-body scans in obese adults. Obesity Silver Spring. By Elizabeth Quinn, MS Elizabeth Quinn is an exercise physiologist, sports medicine writer, and fitness consultant for corporate wellness and rehabilitation clinics. Use limited data to select advertising. Create profiles for personalised advertising. Use profiles to select personalised advertising. Create profiles to personalise content. Use profiles to select personalised content. Measure advertising performance. Measure content performance. Understand audiences through statistics or combinations of data from different sources. Develop and improve services. Use limited data to select content. List of Partners vendors. Health and Safety. By Elizabeth Quinn, MS Elizabeth Quinn, MS. Elizabeth Quinn is an exercise physiologist, sports medicine writer, and fitness consultant for corporate wellness and rehabilitation clinics. Learn about our editorial process. Learn more. Reviewers confirm the content is thorough and accurate, reflecting the latest evidence-based research. Content is reviewed before publication and upon substantial updates. Reviewed by Heather Black, CPT. Learn about our Review Board. Article Talk. Read Edit View history. Tools Tools. What links here Related changes Upload file Special pages Permanent link Page information Cite this page Get shortened URL Download QR code Wikidata item. Download as PDF Printable version. In other projects. Wikimedia Commons. Technique for measuring the density of a living person's body. JAMA reprinted in Obesity Research. doi : Exercise Physiology: Energy, Nutrition, and Human Performance 7th Edition. ISBN

Hydrostatic weighing for scientific research -

The examiner will compare your land scale reading with underwater scale reading to provide an accurate result.

Like we mentioned earlier, Hydrostatic weighing is one of the most accurate methods to calculate body fat. In modern ages, there are CT scans and MRI scans but these scans can have some side effects as well; to prevent these side effects, some people still prefer hydrostatic weighing.

On the other hand, this is inexpensive and less time consuming. The whole process takes up to 15 to 20 minutes. This also helps people to maintain a proper diet because some people being thin can have more body fat and less muscle weight while on the other hand, some trained athletes can have lower body fats and more muscle weight.

These results can make someone happy or upset. However, hydrostatic weighing can be done anywhere with proper equipment; this is not like the other heavy machines present in medical centers.

Some experts offer their services even at home. Give these experts your location and then they will reach out to you. They often have hydrostatic weighing mobile. Underwater weighing has been considered the gold standard for body composition assessment. Scientific studies and research have proven that fats are lighter than bones and muscles.

That is why we use hydrostatic weighing to calculate the body fat percentage corresponding to the water density. If the body has a higher fat ratio, then it will move upward by the force of water. But if the body consists of a lower fat ratio, then it will sink deeper in the water.

As discussed above, tests like MRI scans and CT scans can have side effects, and some people just do not find this suitable. Fitness enthusiasts prefer hydrostatic weighing to other medical procedures. On the other hand, no one likes to pay more; people also prefer underwater weighing because this is a lot less expensive than other tests out there.

The answer to this question relies on multiple factors. These factors make the result as accurate as possible. Before diving into those factors let us clear to you that hydrostatic weighing is considered the gold standard for body composition.

There are other tests too like CT scan and MRI scan. These tests are limited to medical research, and are highly expensive. It is not that easy for one to go and have these tests. This will ultimately lead to a false result. As we know that bones are heavier than fat.

If the bone density will be higher than it can affect the result as well. Hydrophobia means the fear of the water. Some people are afraid of the water and they still want to perform the test.

This fear can cause instability. Some people cannot even submerge their selves inside the water; This type of issue can lead to a wrong end result. However, if you have managed to overcome these little problems then the result will be accurate. Hydrostatic weighing or underwater weighing is still one of the best methods to find body fat composition.

It is a really quick and inexpensive process. The only drawback of underwater weighing is that it is not suitable for every person to get completely submerged inside the water. People are often hydrophobic; this can lead to a false result.

However, there is a minor risk of having a high bone density; this will increase the bone weigh and can cause an error in the final result. Conversely, fat is less dense than water.

Therefore, a large amount of fat mass will make the body lighter in the water and have a higher percent body fat. Body density is expressed as mass per unit volume, where mass is the weight of the body in air Ma and volume is the difference between the weight in air and the weight of the body submersed during underwater weighing Ma — Mw.

Once body density is calculated, it is possible to convert this to a percentage body fat. The process is divided into three steps: 1 measurement of residual volume; 2 measurement of dry bodyweight; and 3 measurement of underwater weight. Figure 1 provides an illustration of one method used for hydrostatic underwater weighing.

An allowance must be made for residual lung volume the air that remains in the lungs after a maximal exhalation as this air increases the participant's buoyancy. It is measured using methods such as closed circuit dilution including helium dilution or nitrogen washout.

If indirect measurement cannot be conducted, it can also be estimated from vital lung capacity or using published equations that are based on age, height.

Hydrostatic underwater weighing typically requires the participant to be completely submerged underwater while exhaling maximally to minimize the effect of buoyancy from lung air. Differences in residual volume determination have been reported to contribute the largest sources of variation.

After having measured or estimated residual lung volume, the participant's dry weight is measured wearing a swimming suit or running shorts. Participants must not eat or engage in strenuous exercise for at least 4 hours before their scheduled appointment.

They should avoid ingesting any gas-producing beverages for at least 12 hours before the test. Participant must wear swim suits. However, as it is mostly only available in research laboratories or university settings, it is generally used for research purposes and not applicable in clinical practice or in large-scale population studies.

It is used less frequently since the introduction of air displacement plethysmography as this technique is better tolerated by participants. Figure 1 Illustration of measurement of underwater body weight. The most commonly used equations for estimating the percent of body fat from density are as follows:.

Considerations relating to the use of hydrostatic underwater weighing for anthropometry in specific populations are described in Table 2.

Refer to section: practical considerations for objective anthropometry. About About the DAPA Measurement Toolkit What's New Other resources Toolkit Team Contact. Introduction Validity Reliability Error and bias Feasibility Data processing Statistical assessment of reliability and validity Harmonisation.

Introduction Subjective methods Objective methods Harmonisation Videos Dietary assessment decision matrix. Introduction Subjective methods Objective methods Harmonisation Videos Physical activity assessment decision matrix.

Introduction Subjective methods Objective methods Anthropometric indices Harmonisation Videos Anthropometry decision matrix. Anthropometry Domain. Hydrostatic underwater weighing. What is assessed? How is the measurement conducted? When is this method used?

How are estimates of body composition derived? Strengths and limitations Populations Further considerations Resources required Instrument library References. Two methods to determine total body water An allowance must be made for residual lung volume the air that remains in the lungs after a maximal exhalation as this air increases the participant's buoyancy.

Dry bodyweight After having measured or estimated residual lung volume, the participant's dry weight is measured wearing a swimming suit or running shorts. Underwater weight The participant climbs into the underwater weighing tank and sits in a seat that hangs from a force load-cell.

After the underwater weight stabilizes approximately 5 seconds , the participant is instructed, though yelling or pounding on the side of the tank, to return to an upright position.

During weighing, the participant is always free to stand up or return to the upright position.

Hydrostatic underwater weighing Resrarch a Hydrostatic weighing for scientific research of densitometry another being air displacement plethysmography Hydrosfatic, which sciemtific body composition from body density and body gesearch. It Monitoring alcohol intake Archimedes' principle of displacement. It is based upon the Hydrostatic weighing for scientific research two-component 2-C model of body composition which assumes that body weight is composed of fat free mass FFM with a constant density of 1. The density of the whole body, therefore, depends upon the relative size of these two components. As bone and muscle are denser than water, a person with a larger percentage of fat free mass will weigh more in the water, and have a lower percent body fat.