A Study of Kazakh Judokas Hypohydration Levels During Training at a Weight-Stable Period
DOI:
https://doi.org/10.31489/3081-0531/2026-2-1-3/14-18Keywords:
hydration, judo, Kazakh judokas, weight-stable period, hypohydration, training session, judo athletesAbstract
Elite judo athletes frequently utilize rapid weight loss (RWL) strategies, which can trigger dehydration during competition periods. While previous research has documented hypohydration during competition, this study aimed to determine the hydration status of elite male and female Kazakh national team judokas during a non-competitive, weight-stable preparation period and to examine changes across a typical training day. A descriptive, repeated-measures study was conducted with 18 competitive judo athletes (9 men and 9 women) from the Kazakh national team. Hydration status was evaluated using urine specific gravity (USG), urine color (UC), and body weight (BW) measured in the morning, immediately before training, and immediately after training. Hypohydration was defined as a USG>1.020 g/mL. Mean USG values did not differ significantly among measurement times (Morning: 1.027 ± 0.006; Pre-training: 1.026 ± 0.005; Post-training: 1.025 ± 0.006; p=0.14). Similarly, UC remained stable across the day (p=0.40). However, BW significantly decreased during the training session (p=0.002), dropping from a pre-training mean of 66.34 ± 16.06 kg to a post-training mean of 65.71 ± 15.78 kg. Hypohydration was highly prevalent: 15 athletes were hypohydrated in the morning, 17 were hypohydrated before training, and all 18 athletes (100 %) were hypohydrated following the training session. Hypohydration is a widespread and persistent condition among elite Kazakh judo athletes, even during weight-stable periods without competitive pressure. The high prevalence of hypohydration suggests that suboptimal fluid intake may be an ingrained habit rather than a response to acute weight-cutting. These findings highlight an urgent need for hydration education and intervention strategies to optimize training quality and protect athlete health.
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