Body Composition MOdels
● Body FATNESS has several models
○ 2 component — most common in health/fitness setting
■ Fat and fat free
■ Ways of calculation
● Densitometry: measures body volume for a calculation of body
density (Db)
○ Db = body mass / body volume
● Hydrodensitometry and body plethysmography (Bod pod):
measures body volume and calculates density
● Athropometry: skinfold measurement
● Hydrostatic wweighing: underwater weighing
○ Originally the “gold standard” — now its ?nexa?
○ Based on 2 component
○ Must measure RV (not estimate)
○ Time consuming
○ Special equipment/expense
○ Subject compliance
○ Skilled technician
○ Skilled subject
○ Based on archimedes’ principle
■ Object immersed in a fluid loses an amount of
weight equivalent to the weight of the fluid
displaced
○ E.g., Volume = [(70.45 kg - 1.95 kg) / 0.99659 kg/L] - (1.6 +
0.1) = 67.0 L
■ Db = 70.45 / 67.0 L = 1.1000 (MUST USE FOUR
DECIMALS)
■ %BF =
■
○ 3 component
○ 4 component
