The body’s relative percentage of fat as compared to lean tissue (bones, muscles, and organs).
The partitioning of body mass into fat- free mass (weight or percentage) and fat mass (weight or percentage).
The relative amount of body weight that is fat and nonfat.
The major structural components of the human body such as muscle, fat, and bone, body density.
The body consists of fat, protein, water, and ash (minerals). Normal bodies usually consist of 16%-20% protein, 3%-5% ash (mineral matter), 10%-12% fat, and 60%-70% water. Age, diet, genetic background, physical activity, hormonal status, and gender can affect not only the proximate composition of the whole body, that is, the magnitude of each of these components, but also their distribution.
Body composition can have a major impact on athletic performance. In some cases a high degree of muscularity (such as bodybuilding, weight lifting, football, and so forth) is essential for optimal performance, while in others (for example, running, etc.) excess muscularity could be a physical hindrance to performance. Similarly, excess body fatness can decrease performance in many sports, yet body fat can be used to the advantage of some athletes (including sumo wrestlers, football lineman, and so on). Determining the optimal level of musculature or fatness for an individual athlete is wrought with problems. For example, not all athletes will perform equally well with identical body compositions. Furthermore, accurate assessment of body composition can be difficult; thus, striving to achieve a particular body fat is not always effective.
The relative percentages of bony minerals, cell mass, lean body mass, body fat, and body water in an organism, and their distribution through the body. Determination of the specific gravity of the body is done to estimate the percentage of fat. This may be calculated by various methods, including underwater weighing, which determines the density of the individual; use of radioactive potassium, 40K; measuring the total body water by dilution of tritium; and use of various anthropometric measurements such as height, weight, and skin fold thickness at various sites. None of these methods is free of the potential for error. Underwater weighing is useful but may provide misleading information when used in analyzing body composition of highly trained athletes. The obese person has a lower body density than does the lean person, because the specific gravity of fat tissue is less than that of muscle tissue. The fat content for young men will vary from about 5% to 27% and for women from about 18% to 35%.
The proportion of body weight that is made up of fat tissue compared to lean tissue.
The amount of body fat compared to lean tissue, such as muscle and bone.
The proportion of fat, muscle, and bone making up the body. Body composition is usually expressed as percent of body fat and percent of lean body mass.
One way to quantify the amount of body fat in relation to the fat-free mass is by using the ratio of these two components. This ratio is often expressed as a percentage of the entire body fat.