Measures of Body Fat and Related Factors in Normal Adults—-H
2d K equivalents
found an average
rerage of 2.521 K
and for 8 women
be attributed to
\ to age as shown
sroup [7].
ody composition
e whatis actually
and bone. They
t exclusive of fat.
This suggestion
‘a as measured in
asons. Potassium
v) and fat. The
fter an equilibra-
od in the sparse
nical analysis of
indirect isotopic
neasured total K
analysis), is thus
men was 51.10+
ation coefficients
‘omen. Correlain and 0.813 for
body weight, is
differs from the
ee de ame
> ranges found by
ow eA eaRialwaeWEllMad ee ee A
+029,
~equiv/kg for the
we NElo ey
thesia Gt
Ips reported here,
above formulas. On the basis of measurements of weight, density, body water,
height and joint diameters at elbow, wrist, knee and ankle on 30 subjects, ALLEN
and co-workers [14] have estimated that 6.8 per cent (2s range =5.7 —7.9 per cent)
of the ‘normally hydrated fat-free body’ is bone mineral. Applying this factor to
LBM (‘normally hydrated fat-free body’ =: LBM), mean bone tissue in our male
subjects would be 3.97 kg and for female subjects 2.84 kg. This estimate of bone
tissue added to mean LBW**° may be assumed equivalent to the mean ‘chemical’
fat-free body. Mean value for men amounts to 55.07 kg and for women 37.11 kg.
These mean values are slightly less than those for ‘chemical’ fat-free body obtained
by subtraction of assumedessential lipids (3.5 per cent of LBM) from mean LBM—
56.38 kg for males and 40.28 kg for females.
In the paragraphs above we have presented two ways of estimating lean body
mass, namely by potassium measurement and by TBW-body density technique. As
has been shown the correlation of these two measurements is very high. However,
this correlation is not as great as that between body fat measured by TBW-body
density and the regression equations using anthropometric measurements (Table 5).
COMPARISON
WITH
PREDICTIONS
OF
OTHER
BODY
ANTHROPOMETRIC
FAT
OR
WEIGHT
It has been emphasized that prediction equations developed from anthropometric
measurements should be compared with measurements of subjects other than those
used for derivation of the equations. From the literature seven formulas were
selected [10, 15-19, 21] which used the variables measured in our study of 167
subjects having body fat measurements. Anthropometric data from the present
study were substituted appropriately in these seven formulas. Correlation coefficients
were determined between the predicted and observed values for each formula and
for each subject category where applicable.
The seven formulas used were as follows:
1.
Youne [15]. Skinfold and percentage standard weight. This was based on 94
women aged 17-30 years measured anthropometrically and by body density.
Specific gravity = 1.0884 —0,0004321 X, —0.0003401 X,,
Where X, =skinfold mid-abdomenline in mm.
X,,= percentage standard weight according to Build and Blood Pressure Study, 1959 (according to HATHAWAY and Foarp [8] for our
data).
aaa
ations in addition
and ‘chemical’ fat-free body = LBW**" + bone mass
Estimates of bone mass and of essential lipids may be made to apply in the
—
28.94-45,82
33.43-69,42
fat-free body. Thus:
‘chemical’ fat-free body = LBM - essential lipids
Lad
20
72
77-122
1.97-3.12
46.93-107.8
27-45
priate corrections of LBM for essential lipids and of LBW*** for bone mass should
result in comparable values which may be considered equivalent to the ‘chemical’
Cc
4
29
2
6
Boge ataeh mem oy abe,
pegs ce
cet
ns
AESaaRAIMI20 Sys, TESA! ss
3.D.
Range
oS
4
84-133
es wie fecS ata,
ee
Cf
25-44 years
1= 24)
fat-free mass as determined by chemical dissection of cadavers only by an undetermined quantity, perhaps 2-5 per cent, of essential phospholipids and cerebrosides present in bone marrow, spinal cord, brain and certain organs [13]. LBM
differs from LBW**° in that it includes bone mass and the essential lipids. Appro-
—
AND RELATED Bopy
1301