Hydration and Fluid Intake in Basketball Players During Training: Comparison of Different Age Categories

TL;DR

In 70 male basketball players from U14 and U21 teams, hydration status and fluid intake during training differed by age: U14 players became more dehydrated, while U21 players improved hydration, and U21 consumed more fluid. The authors conclude that younger athletes may require more guidance and education about proper hydration during training.

Key findings

• A significant time × age-group interaction was found for urine specific gravity (USG): F(1,68) = 23.72, p < 0.001, η² = 0.083. U14 USG increased from 1.020 ± 0.007 pre-training to 1.024 ± 0.006 post-training (p = 0.03), whereas U21 USG decreased from 1.020 ± 0.005 to 1.016 ± 0.008 (p < 0.001).
• U21 players consumed significantly more fluid during training than U14 players: 1.16 ± 0.65 L vs. 0.72 ± 0.50 L (p = 0.003).
• Fluid intake was not significantly correlated with hydration change in either group: U14 r = 0.037, p = 0.845; U21 r = 0.162, p = 0.318.
• Both groups began training at a mean USG of 1.020, which is at the study’s hypohydration threshold (USG ≥ 1.020 g·mL⁻¹); U14 pre-training USG was also significantly higher than U21 post-training USG (p = 0.03).

Methods

• Participants were 70 male basketball players from U14 (n = 30) and U21 (n = 40) teams of a local club in Kastamonu, Türkiye. Inclusion required at least 3 years of competitive basketball experience, active competition in the past year, regular training at least 3 days/week, and no injury preventing training for the past 6 months; athletes using diuretics, medications, or supplements were excluded.
• Data were collected during preparatory training sessions at the same environmental temperature (24.3 ± 1.1 °C). Urine samples were collected before and after training to assess USG via a digital refractometer (ATAGO PAL-10S), and fluid intake was monitored from 2-L bottles given to each athlete.
• Analyses used JASP 0.18.3.0. Normality was checked with Shapiro-Wilk and skewness/kurtosis; independent t-tests compared descriptive variables; repeated-measures ANOVA (2 groups × 2 time points) examined USG change; Pearson correlation examined USG change vs. fluid intake; significance was set at p < 0.05. Post hoc power was 0.88.

Limitations

• Stated: USG variability and sensitivity to recent fluid intake may influence single-time-point measurements; morning USG and 24-h hydration monitoring would better assess baseline and habitual hydration; body mass change was not monitored pre- and post-training; diet and physical activity in the days before testing were not controlled.
• Stated: the pre–post training design specifically targeted in-session hydration management rather than broader daily hydration patterns.
• Evident from the text: the sample was male basketball players from a single local club, so findings may not generalize to female athletes, other sports, or other settings; the study also did not encourage fluid intake, and the correlation analysis does not establish causality.