The Effect of Acute Alkaline Water Ingestion on Hydration, Anaerobic Performance and Fatigue During High-Intensity Exercise

Background: Alkaline water is widely promoted for its hydration and performance benefits, but limited research supports these claims. Objective: This study aimed to compare the effects of alkaline (ALK) versus neutral (NEU) water on hydration and anaerobic performance. Methods: Ten trained males (age: 25.7 ± 4.3 years) participated in a randomized crossover study. In a cross-over study design, participants were dehydrated overnight and rehydrated with 500 ml of either ALK or NEU water. Blood glucose and lactate were measured on arrival (OA), pre-Wingate (PRE), immediately post-Wingate (IMPOST), and one-hour post-Wingate (1HRPOST). Urine-specific gravity and pH were measured OA, PRE, and 1HRPOST. Anaerobic performance was evaluated using three 30-second Wingate tests with a three-minute intra-trial rest intervals. After a seven-day washout, each subject repeated the protocol with the alternate water type. Results: No significant differences were observed between ALK and NEU in blood glucose, lactate, urine-specific gravity, or urine pH (p0.05). In addition, no significant differences occurred between the ALK and NEU conditions in mean peak power, total peak power, or total work (p = 0.142, p = 0.271, p = 0.124). However, fatigue was significantly higher in the ALK condition (71.21% ± 11.16%) compared to NEU (61.01% ± 11.28%, p = 0.002). Conclusion: ALK and NEU may not significantly affect hydration or anaerobic performance in hypohydrated individuals. However, ALK water increased fatigue, suggesting it may impair recovery in repeated anaerobic efforts. Further research is warranted to understand the mechanisms behind this difference.