Rehydration following exercise in the heat: a look at alternative formulations and the role of plasma volume expansion in excess diuresis

Abstract

Rehydrating an athlete or physically active person who incurs dehydration during exercise is important, especially when this person must fully recover within a short period of time such as when practicing twice a day or participating in tournaments. Rapid post-exercise rehydration is difficult to achieve, though, because humans ingesting large fluid volumes will produce large amounts of urine even if they are dehydrated. The goal of this study was to evaluate the strength of acute plasma volume expansion as a stimulus for excess diuresis in the presence of moderate dehydration. This would only be possible if a particular beverage formulation is identified which can result in a significantly lower acute plasma volume expansion from that obtained with water or a conventional sports drink. This beverage would be expected to be better for a quick, effective post exercise rehydration. The results showed no significant differences among the tested beverages. Because some of them had been tested before with different results, further research into this topic is warranted.