Development of BIA equations for estimating body composition of elite male wrestlers
Body composition is associated with successful participating in elite wrestling. Although, BIA is relatively simple, quick, portable and noninvasive method for estimating body composition (Wagner and Heyward, 1999), use of inappropriate equations in BIA measurements can lead systematic prediction errors (Heyward and Stolarczyk, 1996). Therefore, the purpose of this study was to develop bioelectrical impedance equations for estimating body composition (fat free mass) of elite male wrestlers.
Methods: Hundred and eleven highly active elite male senior wrestlers (mean ± SD, age: 21.054±2.993yr, height (H): 171.852±7.518cm, body weight (BW): 78.362±15.931kg) were participated in this study as volunteers. H, BW, bioelectrical impedance analysis (BIA) and hydrostatic weighing (HW) measurements with residual volume were performed at least four hours after breakfast between 11:00 and 13:00 oclock. Each subjects resistance (R), reactance (Xc) and impedance (Z) values were recorded by BIA and fat free mass (FFM) was calculated by using the hydrostatic weighing (HW) measurements as the reference variable. Pearson Correlation Coefficient was used to measure the interrelationship between reference variable (FFM) and independent variables. Then, Multiple Linear Regression Analysis was performed using the FFM as the reference variable and other measured items as the explanatory variables in order to form prediction regression equations (EQ) for BIA. Finally, validity of the equations was examined with Cross Validation Method.
Results: Five equations were derived for FFM to use in BIA measurements. The explanatory variables of the equations were BW, R, height squared (Hsqr), Xc, Z, resistance index (Hsqr/R) and impedance index (Hsqr/Z). The multiple coefficient of determination (R square= Rsqr) and standard error of estimate (SEE) of the equations are given as followed: Rsqr =0.98384, SEE =1.45821kg (EQ1); Rsqr =0.98375, SEE =1.46214kg (EQ2); Rsqr =0.98543, SEE =1.37370kg (EQ3); Rsqr =0.98533, SEE =1.37825kg (EQ4) and Rsqr =0.98613, SEE =1.36336kg (EQ5). By the use of Stepwise Linear Regression Analysis, the results of this study indicated that BW, R, Hsqr, and Xc as ideal explanatory variables to estimate FFM of elite male wrestlers in BIA measurements. Final prediction equation and its Rsqr and SEE are given as followed: FFM= 19.69292 + 0.5233 (BW) 0.05256(R) + 0.00085(Hsqr) + 0.11211(Xc); Rsqr = 0.98613, SEE= 1.36336.
Conclusion: Finally, cross validated prediction equations with high Rsqr and low SEE were derived for FFM of elite male wrestlers to use in BIA measurements. Population specific equations should be developed for accurate estimation of body composition in specific homogeneous groups.
© Copyright 2009 14th annual Congress of the European College of Sport Science, Oslo/Norway, June 24-27, 2009, Book of Abstracts. Published by The Norwegian School of Sport Sciences. All rights reserved.
|Subjects:||body indices fat muscle bone wrestling freestyle wrestling Greco-Roman wrestling analysis auxiliary device investigation method measuring procedure high performance sport elite sport|
|Notations:||combat sports biological and medical sciences|
|Published in:||14th annual Congress of the European College of Sport Science, Oslo/Norway, June 24-27, 2009, Book of Abstracts|
|Editors:||S. Loland, K. Boe, K. Fasting, J. Hallen, Y. Ommundsen, G. Roberts, E. Tsolakidis|
The Norwegian School of Sport Sciences
|Document types:||congress proceedings