Body Composition

overweight

excessive weight for height and does not consider body composition

intra-abdominal fat

fat stored deep in the abdominal cavity and carries a high risk for certain diseases

essential fat

fat that is necessary for normal biological function

fat free mass

includes all tissues exclusive of fat (muscle, bone, organs, fluids)

dual energy x-ray absorptiometry (DEXA)

measuring body composition; bone mineral density, quantification of fat, and lean tissue using very low exposures to radiation, normally used to scan for osteoporosis, and is very expensive

underwater weighing

measuring body composition; gold standard; most accurate indirect measurement techniques; people with more muscle mass weigh more in water than those with less

skinfold measurement

measuring body composition; one of the most economical ways to measure body composition, and when performed by skilled technitions, correlate well with hydrostatic weighing

biomedical impedance analysis

measuring body composition; uses a low level single frequency electric current to measure body composition

air-displacement plethysmography

measuring body composition; uses air displacement rather than water displacement for assessing body composition by sitting in the bod pod

height/weight tables

method of measuring body-weight status; do not reflect body composition and are poor instruments for weight loss recommendations

body mass index (BMI)

method of measuring body-weight status; the ratio of body weight in kilograms to height in meters squared

18.5-24.9

normal BMI

obesity 25, 35

overfatness; greater than these percents in men and women

body composition

the ratio between fat and fat free mass

3-5

% essential fat for men

8-12

% essential fat for women

wait to hip ratio

a simple method for determining body fat distribution and can also predict disease risk