Effects of hydration strategies on physiological and performance parameters in national level school athletes

The study was conducted as a randomized, counterbalanced crossover study to determine the relative effectiveness of four hydration drinks on various physiological and performance criteria in the adolescent athletes playing on the national school level (n=23). The drinks under investigation were Jeevani (J) a conventional electrolyte solution; plain water (W); a commercially available carbohydrate-electrolyte sports drink (Y) and king coconut water (KC). All the participants were subjected to a standardized endurance exercise protocol at each beverage condition and there was 7 days wash out between the sessions. The state of hydration was measured utilizing bioelectrical impedance analysis (BIA) to estimate the overall body water changes and through determining the rate of sweat. Aerobic capacity (maximal oxygen uptake (VO 2 max) measured using the multi-stage beep test), neuromuscular performance (dominant and non-dominant handgrip strength and vertical jump), psychomotor (reaction time in the drop-stick test), cardiovascular responses (heart rate and blood pressure kinetics), and subjective performance (visual analogue thirst scale and symptom checklist) were performance measures. Shapiro-Wilk tests was used to assess normality of data, test of Friedman and repeated-measures ANOVA with Greenhouse-Geisser correction was used to determine statistically significant differences. Post-hoc comparisons were performed using Wilcoxon signed-rank tests and a Bonferroni-adjusted significance level of 0.0083. There was a significant overall impact of of the beverage used for the intervention (p < 0.001). The isotonic solution had better hydration effects with little fluid loss, the lowest sweat rate (2.10 ml/min) and a positive body mass change (+0.10 kg), and the highest VO 2max (44.8 ± 4.9 ml kg⁻¹ min⁻¹). King Coconut water also exhibited good fluid retention as compared to plain water. Jeevani enhanced handgrip strength (44.0 ± 5.1 kg) and had a positive subjective thirst rating. On the other hand, plain water always resulted in larger loss of sweat, slower rate of heart-rate recuperation and symptoms. Overall, the beverages that were found to be more effective in maintaining euhydration and improving performance during prolonged exercise sessions were electrolyte based and natural coconut water compared to plain water.