The impact of post-exercise hydration with deep-ocean mineral water on rehydration and exercise performance.

Background: Dehydration caused by prolonged exercise impairs thermoregulation, endurance and exercise performance. Evidence from animal and human studies validates the potential of desalinated deep-ocean mineral water to positively impact physiological and pathophysiological conditions. Here, we hypothesize that deep-ocean mineral water drawn from a depth of 915 m off the Kona, HI coast enhances recovery of hydration and exercise performance following a dehydrating exercise protocol compared to mountain spring water and a carbohydrate-based sports drink.

Findings: Subjects (n = 8) were exposed to an exercise-dehydration protocol (stationary biking) under warm conditions (30 °C) to achieve a body mass loss of 3 % (93.4 ± 21.7 total exercise time). During the post-exercise recovery period, subjects received deep-ocean mineral water (Kona), mountain spring water (Spring) or a carbohydrate-based sports drink (Sports) at a volume (in L) equivalent to body mass loss (in Kg). Salivary samples were collected at regular intervals during exercise and post-exercise rehydration. Additionally, each participant performed peak torque knee extension as a measure of lower body muscle performance. Subjects who received Kona during the rehydrating period showed a significantly more rapid return to pre-exercise (baseline) hydration state, measured as the rate of decline in peak to baseline salivary osmolality, compared to Sports and Spring groups. In addition, subjects demonstrated significantly improved recovery of lower body muscle performance following rehydration with Kona versus Sports or Spring groups.

Conclusions: Deep-ocean mineral water shows promise as an optimal rehydrating source over spring water and/or sports drink.