| Background. The ability to routinely track changes in lean mass (LM) is of interest to coaches and physiologists. This is particularly true for athlete populations wherein changes in LM may influence performance. Bioelectrical impedance analysis (BIA) may address this need, however at present its' ability to estimate lean mass (LM) in athletes is unknown. Also unknown is whether the BIA methodology (i.e. arm-to-leg or leg-to-leg) affects the prediction of LM in athletes.;Methods. Fifty-six male and forty-two female athletes were recruited according to training frequency (recreational vs. elite) and training modality (endurance vs. resistance trained). BIA arm-to-leg resistance and leg-to-leg resistance were measured using tetrapolar BIA analyzers manufactured by RJL (RJL Systems, Detroit, MI) and Tanita (Tanita Corporation, Tokyo, Japan) respectively. LM was measured by dual-energy X-ray absorptiometry (DXA) and total body water by deuterium dilution.;Results. The impedance index for both the arm-to-leg (Ht2/R) and leg-to-leg (LL2/R) methods was used to predict LM values in all groups. A comparison of regression lines when BIA-LM and DXA-LM values were regressed revealed no differences (p > 0.05) independent of training frequency and modality or gender. Moreover, BIA-measured LM in the male and female groups was not different (p > 0.05) when compared to controls, independent of the BIA method.;Conclusions. Training frequency and modality do not appear to affect either arm-to-leg or leg-to-leg BIA prediction of LM. Moreover, the impedance index is a strong independent correlate of DXA-LM and thus, BIA shows promise as field method for determining the LM of athletes.;Objectives. First, to determine whether BIA-predicted-LM is influenced by training frequency and modality independent of gender. Second, to determine if the relationship between BIA-predicted-LM is influenced by the BIA method employed to measure resistance (i.e. arm-to-leg or leg-to-leg). |
