Předsoutěžní redukce tělesné hmotnosti a její vliv na tělesné složení

The aim of our study was to monitor changes in individual components of body composition due to reduction in body weight in judo. This precontest weight reduction is very common in combat sports and it can have negative impact not only on performance but also on health. Research group consisted of 11 judoists at the age of 17-27 years belonging to the representation of the Czech Republic. The measurement of body composition had two parts; the first was before body weight reduction and the second part at the end of body weight reduction. For the measurement of body composition we used multifrequency bioimpedance analyzer BIA 2000 - M. The results of our study show that rapid intensive weight reduction is reflected in varying degrees in all parameters of body composition. We noticed a reduction of body weight by an average of 4.7% (approximately 3.8 kg), the weight loss ranged from 1.6 kg to 8.1 kg. The greatest changes in the parameters of body composition were detected in the extracellular water (ECW), there was a decrease of this parameter on average by 13.8 %, while total body water (TBW) decreased by 6.0 %. There was also a reduction in the amount of body fat by 13.2 %, the amount of extracellular mass (ECM) decreased by 9.8 %, the ratio of ECM/BCM by 8.9 % and the amount of fat-free mass (FFM) decreased by 4.0 %. Only in intracellular water (ICW), we noticed a slight increase by 1.4 %, which may be due to the redistribution of body fluids.