Journal of Martial Arts Anthropology

Abstract - Hydration status of youth Judo athletes during an off-season training camp

Problem and Aim. There is a lack of scientific literature about hydration status changes of combat athletes during different periods over a one-year training cycle. The aim of this study is to evaluate the hydration status in youth judo athletes during an off-season 5-day judo training camp.
Methods. The research sample was composed of six judo athletes, age 16 (IqR=3.25), body weight 81 (IqR=18.75) kg, height 179 (IqR=6.5) cm, sports age 9.5 (IqR=3.5). Morning urine samples in test-tubes were collected from athletes´ rooms and analysed using a digital refractometer ATAGO PAL-10S for urine specific gravity (USG). The data was analysed using a non-parametric ANOVA for repeated measures (Friedman´s ANOVA) with the calculation of effect size (Kendall´s Coefficient of Concordance). The results were expressed as a median (Med) with interquartile range (IqR). The statistical significance was set at p<0.05.
Results. After the first morning measurement, the participants were hypohydrated USG=1.0235 (IqR=0.0100). Next day the participants were still hypohydrated USG =1.0259 (IqR=0.0154) and the values were even worse than the previous day. The USG values tended to improve on the 4th day USG=1.0195 (IqR=0.0100) and 5th day as well USG=1.0177 (IqR = 0.0100) and athletes were only minimally hypohydrated. However, there was no significant difference between all measurements (p=0.334) and the effect size was small (Kendall´s W =0.189).
Conclusions. Even though judo athletes trained off-season when body weight reduction was not necessary their hydration status was still suboptimal.