Subjects: healthy adults from New York (328 for model development, 49 for validation)
Examination: abdominal MRI scan
Parameters:
(1) area of skeletal muscle in an abdominal cross-section taken 5 cm above the L4-L5 intervertebral disc, in square cm
(2) area of adipose tissue in an abdominal cross section taken 5 cm above the L4-L5 intervertebral disc, in square cm
skeletal muscle volume in liters =
= (0.166 * (area of skeletal muscle)) + 2.142
mass of skeletal muscle in kilograms =
= (skeletal muscles volume) * 1.047
adipose tissue volume in liters =
= (0.068 * (area of adipose tissue)) + 4.142
mass of adipose tissue in kilograms =
= (adipose tissue volume) * 0.923
fat-free mass =
= (total body mass in kilograms) - (adipose tissue mass)