TERMINOLOGY A complete glossary of body composition and health-related definitions

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Abdominal Obesity (central obesity)
Abdominal obesity is characterized by excessive subcutaneous and visceral fat in the abdominal region, and is also known as upper body obesity. Abdominal Obesity is one of the components of metabolic syndrome (MetS), a cluster of conditions that increase one’s risk of heart disease, diabetes, and stroke.

Accuracy is the quality or state of being correct or precise. Because the human body is being measured, precise methods must be used to obtain accurate data. By being accurate, results will be precise for comparison and to record positive results.

Active Metabolic Rate (AMR)
Active metabolic rate is the fact that you’re consciously aware of your activity . In an average day, the body burns more calories than at rest. AMR is the total amount of calories expended throughout the day due to activities like walking, dancing, reading, running, etc.

Adipose Tissue
Adipose Tissue is made of Fat (~83%) plus its supporting structures (~2% protein) and (~15% water). Adipose tissue is the tissue specialized for storage of triglyceride fat; found under the skin in the hypodermis (thickest layer of the skin) or in the surrounding the abdominal visceral areas.

Android Obesity
Android obesity is a type of obesity in which excess fat is localized on the trunk and abdomen, also referred to as upper-body obesity. Individuals are characterized as having an “apple-shaped” body. Most frequently seen in men, those classified as having android obesity are said to have a poorer prognosis for morbidity and mortality than the gynecoid type.

Anthropometric Measurements
Anthropometric measurements are measurements of body size and proportions including skinfold thickness, circumferences, bony widths and lengths, stature, and body weight

Atherosclerosis is a condition in which an artery wall thickens as a result of the accumulation of fatty materials, such as cholesterol. It is a syndrome affecting arterial blood vessels, a chronic inflammatory response in the walls of arteries, caused largely by the accumulation of macrophage white blood cells and promoted by low density lipoproteins (plasma proteins that carry cholesterol and triglycerides) without the adequate removal of fats and cholesterol from the macrophages by functional high density lipoproteins.


Basal Metabolic Rate (BMR)
BMR is the minimal rate of energy expenditure an organism uses to maintain vital functions.

Bioelectrical Impedance Analysis
This is a body composition method that measures impedance by sending a small alternating current throughout the human body. Bioelectrical Impedance Analysis is able to reflect total body water through the use of the impedance index equation based on the impedance values generated. Fat free mass is determined using the physiological principle that 73% of fat free mass is water. Fat mass is determined by subtracting fat free mass from total body weigh,t and proteins and minerals are proportional to an individual’s fat mass.

Body Cell Mass
The total mass of all the cellular elements in the body which constitute all the metabolically active tissue of the body. A depletion of the body cell mass (BCM) may be indicative of a potential body common with chronic diseases such as AIDS and terminal cancer. BCM includes muscle tissue, organ tissue, intracellular and extracellular water and bone tissue. In normally nourished individuals, muscle tissue accounts for approx. 60% of the BCM, organ tissue accounts 20% of BCM, with remaining 20% made up of red cells and tissue cells.

Body Mass Index (BMI)
Body mass index is a heuristic process or method for determining human body fat based on an individual’s weight and height. BMI is defined as the individual’s body weight divided by the square of his or her height as in BMI=(mass (kg))/(height (m^(2)) ). BMI doesn’t actually measure the percentage of body fat; it gives the ratio of weight to height squared.

Bone Mineral Content
Bone mineral content refers to the amount of mineral per square centimeter of bones. Bone mineral content is composed of calcium, sodium, potassium.

Brown Adipose Tissue
Also known as brown fat, brown adipose tissue’s primary function is to generate body heat in mammals. This type of fat is especially capable of converting the chemical energy from food into heat. Brown adipocytes contain numerous small droplets of lipid and have a high number of mitochondria that contain iron, which makes the color brown, hence the name “brown adipose tissue”. Brown fat also contains more capillaries than white fat because brown fat needs more oxygen than most tissues.


Cancer is a large group of different diseases involving unregulated cell growth. In cancer patients, cells divide and grow uncontrollably, forming malignant tumors, and invade nearby parts of the body. Carcinoma: cancers derived from epithelial cells. This group includes many of the most common cancers, particularly in the aged, and includes nearly all involving tumors in the breast, prostate, lung, pancreas, and colon. Sarcoma: cancers arising from connective tissue (bone, cartilage, fat, nerve) each of which develop from cells originating in mesenchymal cells outside the bone marrow.

Capacitance is the ability of a system to store and release an electric charge.

CT (Computerized Tomography) Scans
CT is a radiographic method that measures the differences in attenuation of x-ray beams as they pass through the body to create a computer-generated image of the scanned area; used for regional assessment of bone, adipose tissue, and lean tissue.


Densitometry describes a measurement of total body density. Hydrodensitometry (underwater weighing) and air displacement plethysmography (BODPOD) are examples of densitometric methods.

Diabetes is a group of metabolic diseases in which a person has high blood sugar because the body does not produce enough insulin or because the cells in the body do not respond to the insulin that is produced. High blood sugar produces the symptoms of polyuria (frequent urination), polydipsia (increased thirst), and polyphagia (increased hunger). There are 3 main types of diabetes. Type 1: results from body's failure to produce insulin and requires the person to inject insulin; type 2: results from insulin resistance, and is a condition where the cells fail to use the insulin properly; type 3: gestational diabetes: when pregnant women, who never had diabetes before, have a high blood glucose level during pregnancy, which can develop into type 2 diabetes.

Dietetic Therapy
Dietetic therapy is used to control one's diet. In order to cure disease, the patient's diet must be curbed in order to be relieved of symptoms. Diabetes, kidney disease, gastrointestinal disorders, liver disease, heart disease can be managed with the help of diet therapy designed by nutritionists because they monitor their patients closely, controlling what they can and cannot consume. Through these means, nutritionists can improve their patients' well beings.


Edema is abnormal accumulation of fluid beneath the skin or in one or more cavities of the body that produces swelling. Generally, the amount of interstitial fluid is determined by the balance of fluid homeostasis, and increased secretion of fluid into the interstitium or impaired removal of this fluid may cause edema.

Empirical Data
Empirical data is information obtained by observation and experiment. Things such as age, gender, and weight are considered empirical data.

Essential Lipids
Essential Lipids are compound lipids (phospholipids) needed for cell membrane formation; approximately 10% of the total lipid pool is essential lipids.

Extracellular Water
Extracellular Water (ECW) is defined as plasma water, interstitial water, transcellular water, and water found in bone, cartilage, and dense connective tissues.


Fat Free Mass
Fat Free Mass is Total Body Mass minus fat. Fat Free Mass includes skin, bones, ligaments, tendons, organs, water content, and all other elements that contribute to weight that is not attributed to fat.

Fatty Liver
Fatty liver disease is a reversible condition where large vacuoles of triglyceride fat accumulate in liver cells via the process of steatosis. Despite having multiple causes, fatty liver can be considered a single disease that occurs worldwide in those with excessive alcohol intake and those who are obese. This condition is also associated with other diseases that influence fat metabolism. Fatty liver is commonly associated with alcohol or metabolic syndrome (diabetes, hypertension, obesity, dyslipidemia) but can also be due to many other causes.

Field Methods
Field methods are methods suitable for estimating body composition in practical settings, for example skinfolds, bioimpedance analysis, and anthropometry.


Gynoid Type Obesity
Gynoid type obesity is a type of obesity in which excess fat is localized in the lower body, also referred to as lower-lower body obesity. Individuals are characterized as having a “pear-shaped” body. Common to both sexes, though females are more affected.


Heart Disease
Heart disease describes a range of conditions that affect your heart. Diseases under the heart disease umbrella include blood vessel diseases, such as coronary artery disease; heart rhythm problems (arrhythmias); and heart defects you're born with (congenital heart defects), among others. The term "heart disease" is often used interchangeably with the term "cardiovascular disease." Cardiovascular disease generally refers to conditions that involve narrowed or blocked blood vessels that can lead to a heart attack, chest pain (angina), or stroke.

Hydrostatic Weighing
Hydrostatic weighting is a body composition method used to estimate body volume via measurement of weight loss when the body is totally submerged underwater. This is a method of hydrodensitometry, and is sometimes referred to as underwater weighing.

AKA hydropathy, hydrotherapy involves the use of water for pain relief and treating illness. It is a course of medical treatment, and is a generic term for water therapies using jets, underwater massages, and mineral baths. Treatments use physical properties such as temperature and pressure for therapeutic purposes, to stimulate blood circulation and treat the symptoms of certain diseases.

Hyperglycemia is the technical term for high blood glucose (blood sugar). High blood glucose happens when the body has too little insulin or when the body can't use insulin properly.

Hyperlipidemia refers to higher than normal lipid levels. Lipid is the scientific term for fats in the blood. At proper levels, lipids perform important functions in your body, but can cause health problems if they are present in excess. Hyperlipidemia includes several conditions, but it usually means that you have high cholesterol and high triglyceride levels.

Hyperplastic Obesity
Hyperplastic obesity is characterized by an increase in the number of adipose cells, as opposed to adult onset hypertrophic obesity, in which adipose cells increase in size due to stored fat. Hyperplastic obesity results from overfeeding during the first few weeks of infancy, and is typically a lifelong condition. Hyperplastic obesity is defined as excessive weight gain in childhood and is characterized by the creation of new fat cells.

Hypertension, or high blood pressure, is a chronic medical condition in which the blood pressure in the arteries tends to stay elevated. This requires the heart to work harder than normal to circulate blood through the blood vessels and can lead to the damage of the heart and other vital organs throughout the body such as the kidneys and lungs. Normal blood pressure is below 120/80 mmHg and hypertension or high blood pressure is present when above 140/90 mmHg. There is primary hypertension and secondary hypertension. Primary hypertension is high blood pressure with no obvious underlying medical cause and secondary hypertension is caused by other conditions that also affect the kidneys, arteries, heart or endocrine system.


Impedance is the frequency-dependent opposition of a conductor to the flow of an alternating electric current. Impedance is composed of two main properties, resistance and reactance.

Intracellular Water
Intracellular Water (ICW) is found in the cytosol of every cell in the body. ICW is calculated based on impedance values at multiple frequencies.

Intracellular Water/Extracellular Water
Within the human body, total body water is separated into intracellular and extracellular water. Intracellular water is the water enclosed within a cell membrane. Extracellular water is all the remaining water that is not enclosed within a membrane.


Lean Body Mass
Lean Body Mass is Fat Free Mass plus essential lipids.

Lean Soft Tissue Mass (DEXA Term)
Lean Soft Tissue is Soft Tissue minus fat.

Leptin is energy-regulating protein, secreted by adipocytes.

Lymphedema refers to swelling that generally occurs in one of your arms or legs, sometimes both in arms or legs, and occasionally in the chest. Lymphedema is most commonly caused by the removal of or damage to your lymph nodes as a part of cancer treatment. It results from a blockage in your lymphatic system, which is part of your immune system. The blockage prevents lymph fluid from draining well, and the fluid buildup leads to swelling. There is no cure for lymphedema, but can be managed with early diagnosis and diligent care of your affected limb.


Malnutrition Edema
Malnutrition edema occurs due to a decrease in nutrition and consumption of proteins. Malnutrition edema is caused due to a decrease in serum albumin.

Metabolically Healthy Obese (MHO)
This body type is someone who has excessive body weight without having any metabolic conditions (insulin resistance) commonly seen in standard obese individuals.

Metabolic Syndrome (MetS)
In adults, is MetS is defined as abnormal values for three or more of the harmonized criteria: waist circumference, triglycerides, HDL-Cholesterol, blood pressure, or glucose.

Minerals include essential nutrients the body needs to survive and carry out daily functions and processes. Minerals enter the system by eating plants that absorb them from the earth and by eating meat from animals, which graze on plants.

MRI (Magnetic Resonance Imaging)
MRI is a technique used to create computerized cross-sectional images of the human body from radio frequency signals emitted by hydrogen nuclei.

Multi-Frequency Analysis
InBody uses multiple frequencies to allow for a series of impedance values, which provide a more accurate reflection of the individual’s body composition. The frequency range applied is generally 1kHz to 1MHz.

Muscular Obesity
This body type has an increased amount of both muscle and weight therefore is referred to as being muscular obese. This body type is usually found in body builders.


Obesity is a medical condition in which excess body fat has accumulated to the extent that it may have an adverse effect on health, leading to reduced life expectancy and/or increased health problems. Body mass index (BMI), a measurement which compares weight and height, defines people as overweight (pre-obese) if their BMI is between 25 and 30 kg/m^2, and obese when it is greater than 30 kg/m^2.


Percent Body Fat
A person’s body fat percentage is the total weight of the person’s fat divided by the person’s weight and consists of essential body fat and storage body fat. Our bodies require essential fat because it serves as an important metabolic fuel for energy production and other normal bodily functions. The percentage of essential body fat for women is greater than that for men. Essential fat for men: 3-5% and women: 8-12%. Storage fat is located around internal organs (internal storage fat) and directly beneath the skin (subcutaneous storage fat). It provides bodily protection and serves as an insulator to conserve body heat. The relationship between subcutaneous fat and internal fat may not be the same for all individuals and may fluctuate during the life cycle. The formula to calculate the percentage of body fat is: Percent Body Fat (%)= (body fat mass (kg))/(weight (kg)) ×100

Phase Angle
A bioimpedance measurement calculated as the arc tangent of the ratio of reactance to resistance.

Postpartum Obesity
Pregnant patients are subject to obesity due to increase of weight. Those who have previously suffered from obesity must be careful in order to not become obese again after pregnancy.

Proteins are polymer chains of amino acids linked together by peptide bonds. Proteins are nutrients that are needed by the human body for growth and maintenance. Protein is the most abundant molecule in the body. It is found in cells of the body and is a major structural component of all cells in the body, especially muscle. It is also found in includes body organs, hair, and skin. Proteins are utilized in membranes ex. glycoproteins. Proteins help regulate metabolism, support the immune system, and other body functions. Also, proteins are needed to form blood cells.


Reproducibility is the ability to produce a copy of something, or to show or do something again. High accuracy and reproducibility are essential when the human body is being analyzed.

Resistance is the ratio of voltage across an object to the current through the object i.e. the ability of a material to slow an electrical current.

Respiratory Gas Analysis
Respiratory gas analysis is used when a patient is hooked up onto a breathing analysis machine while on an exercise equipment. While exercising, the patient is tested by breathing in and out, thus analyzing the respiratory system. With this method, we can test the cardiopulmonary results of the patient. It is a method for gaining noninvasive information on the clinical state of an individual by monitoring volatile organic compounds present in the exhaled breath. Breath gas concentration can then be related to blood concentrations via mathematical modeling, as for example in blood alcohol testing.

Resting Energy Expenditure
Is the amount of energy, usually expressed in kcal (food calories), required for a 24-hour period by the body during resting conditions. It is closely related to, but not identical to, basal metabolic rate.


Sarcopenic Obesity
Sarcopenic obesity is a medical condition in which a person shows an increase in fat mass and a decrease in lean mass. Sarcopenia means loss of muscle, and obesity is the increase in fat percentage. This disease can be caused by various reasons. Problems may arise in diagnosing a person with sarcopenic obesity because there is no reference value for the appropriate lean mass. Possible cures are weight training and weight loss programs.

Segmental Analysis
Segmental analysis views the body as 5 cylinders; right arm, left arm, trunk, right leg, left leg. Applied to BIA technology, segmental analysis allows for each part of the body to be analyzed independently. The five cylinders are analyzed independently based on the segmental voltage/current overlap

Skeletal Muscle
Skeletal muscle represents the majority of muscle tissue; it is the type of muscle that powers movement of the skeleton. It is categorized as striated muscle because when viewed under a light microscope, alternating stripes of light and dark bands can be seen. There are three muscle types, cardiac, smooth, and skeletal muscle. Skeletal muscle is innervated by the somatic nervous system and subject to voluntary control. Skeletal muscle is attached to the bone and its main function if for movement of the body. This is the muscle that is influenced the most by physical activity.

Skinfold Thickness
The skinfold measurement test is one common method of determining a person’s body composition and body fat percentage. This test estimates the percentage of body fat by measuring skinfold thickness at specific locations on the body. The thickness of these folds is a measure of the fat under the skin, also called subcutaneous adipose tissue. Two measurements are recorded and averaged.

Soft Tissue
Soft Tissue is the combination of tendons, ligaments, fascia, skin, fibrous tissues, fat, and synovial membranes (connective tissue), and muscles, nerves, and blood vessels (which are not connective tissue).

Subcutaneous Fat
Subcutaneous fat is adipose tissue stored beneath the skin. Subcutaneous fat can be measured using body fat calipers, which give a rough estimate of total body adiposity, since approximately 50% of body fat is found in the subcutaneous layer of the skin.


Total Body Water
A significant fraction of the human body is composed of body water. In diseased states, body water may be affected and become unbalanced. Body water is regulated by hormones, including the anti-diuretic hormone (ADH), aldosterone and atrial natriuretic peptide. Intracellular fluid takes up 2/3 of the body water. Extracellular fluid takes up 1/3 of the body water. Within the extracellular fluid is plasma, and that takes up 1/5 of the extracellular fluid. Interstitial fluid takes up 4/5 of the extracellular fluid. Transcellular fluid is the “third space” but is normally ignored in calculations. Transcellular fluid is contained inside organs such as the gastric fluid, cerebrospinal fluid, peritoneal fluid, and ocular fluids.


Upper Body and Lower Body Balance
Precise analysis of body composition and upper lower balance makes up the right and left arm, body, right and left leg muscles. This output allows shows whether or not the muscle in the body is proportional/balanced or if it is unbalanced (more muscle in the arms than the legs). Maintaining upper and lower body balance is important for maintaining your overall health.

Urine Specific Gravity
Urine Specific Gravity is a way to determine the hydration status of patients. This test is performed by obtaining a urine sample, then performing a set of laboratory procedures in order to determine the gravity of the urine. The reference gravity value is 1.0, which is the value for water. The higher the patient’s value is, the more likely that individual is dehydrated as their urine is much more concentrated.


Visceral Fat
Visceral Fat is the fat surrounding your major organs. An accumulation of visceral fat can contribute to increased risk of Insulin-Resistant Diabetes, Heart Disease, Stroke, and even Dementia.


8-point Tactile Electrodes with Patented Thumb Electrodes
One of InBody’s four core technologies. The 8-point tactile electrodes with patented thumb electrodes allow the five cylinders of the body to be measured and analyzed independently of each other. The separation of the electrodes allows for reproducibility in measuring impedance, allowing for the voltage and current overlap measurement to begin at the same place every time. The separation of the voltage and the current vis-à-vis the thumb electrode is imperative to the reproducibility of this device, because regardless of hand placement and/or size of the hand on the electrode, the measurement of current and voltage drop overlap will begin at the same place every time.
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