Validity and reliability of bioelectrical impedance analysis and skinfold thickness in predicting body fat in military personnel.
Previous studies show that body composition is related to injury risk and physical performance in soldiers. Thus, valid methods for measuring body composition in military personnel are needed. The frequently used body mass index method is not a valid measure of body composition in soldiers, but reliability and validity of alternative field methods are less investigated in military personnel. Thus, we carried out test and retest of skinfold (SKF), single frequency bioelectrical impedance analysis (SF-BIA), and multifrequency bioelectrical impedance analysis measurements in 65 male and female soldiers. Several validated equations were used to predict percent body fat from these methods. Dual-energy X-ray absorptiometry was also measured, and acted as the criterion method. Results showed that SF-BIA was the most reliable method in both genders. In women, SF-BIA was also the most valid method, whereas SKF or a combination of SKF and SF-BIA produced the highest validity in men. Reliability and validity varied substantially among the equations examined. The best methods and equations produced test-retest 95% limits of agreement below ±1% points, whereas the corresponding validity figures were ±3.5% points. Each investigator and practitioner must consider whether such measurement errors are acceptable for its specific use.
Department of Norwegian School of Sport Sciences-Defence Institute, The Norwegian Defence University College, P.O. Box 4014, Ullevaal Stadion, N-0806 Oslo, Norway.
Anders
A
Aandstad
Department of Sports Medicine, Norwegian School of Sport Sciences, P.O. Box 4014, Ullevaal Stadion, N-0806 Oslo, Norway.
Kristian
K
Holtberget
Department of Norwegian School of Sport Sciences-Defence Institute, The Norwegian Defence University College, P.O. Box 4014, Ullevaal Stadion, N-0806 Oslo, Norway.
Rune
R
Hageberg
Department of Sports Medicine, Norwegian School of Sport Sciences, P.O. Box 4014, Ullevaal Stadion, N-0806 Oslo, Norway.
Ingar
I
Holme
Department of Sports Medicine, Norwegian School of Sport Sciences, P.O. Box 4014, Ullevaal Stadion, N-0806 Oslo, Norway.
Sigmund A
SA
Anderssen
D050154:Adiposity; D000293:Adolescent; D000328:Adult; D017097:Electric Impedance; D005260:Female; D006801:Humans; D008297:Male; D008889:Military Personnel; D009664:Norway; D015203:Reproducibility of Results; D012885:Skinfold Thickness; D055815:Young Adult