Metabolomic Analysis of the Impacts of Hydration Status on Exercise Performance

Exercise-induced dehydration is very common in athletes and regularly active individuals. Hypohydration, if sufficiently severe, can negatively impact physical performance and mental capacity. Development of an efficient rehydration therapy could prove beneficial in these circumstances. Multiple animal studies have shown the positive effects of desalinated deep-sea mineral water on various physiological conditions. The beneficial effects of deep-sea mineral water may be attributed to its unique mineral composition, particularly magnesium, which is highly abundant in deep-sea water. The investigators wish to evaluate whether a similar response occurs in post-exercise rehydration using deep ocean water from a different source. Kona Deep is marketed as Hawaiian glacier water drawn from a depth of 915 m off the Kona coast that is naturally rich in electrolytes and nutrients, and that is free of mercury, harmful bacterial, and pollutants, making it a desired drinking water source. Accordingly, the investigators will investigate whether subjects administered Kona Deep following an exercise challenge undergo more rapid rehydration and demonstrate higher peak power production compared to subjects administered commercially available liquids. Euhydrated subjects in this study will be exposed to an exercise-challenge protocol (stationary biking) under warm conditions (30°C) to accelerate dehydration. Dehydration will be measured as a body mass loss of 3-5% (maximum exercise time will be 180 minutes). A body mass loss of 3% is the minimal amount lost during a similar exercise-dehydration protocol but where significance was still observed in exercise performance, recovery, and physiological parameters. During the post-exercise recovery period, subjects will consume one of three liquids in a volume equivalent to 1.5 times the body mass lost. Rehydration measured by salivary and urinary osmolality and exercise recovery will be measured such as oxygen consumption (VO2) at 60% estimated maximal heart rate and peak power production by contraction of the knee extensors before exercise, immediately after exercise, and after the rehydration period.