ABSTRACT

This chapter explores the role of water as an essential nutrient and the physiological basis of hydration. In hydration science, the effect of any beverage on body fluid status is judged by the balance between how much the body retains of any volume that is consumed. Since most fluid consumed by athletes is co-ingested with meals and/or snacks, the influence of food on rehydration has significant practical application. A low-alcohol beer with added sodium may provide a compromise to the dehydrated athlete following exercise, in that it is a beverage with high social acceptance that avoids the poor fluid retention observed with full-strength beer. The timing of consumption relative to the exercise bout has a significant influence on beverage recommendations given to athletes to optimise performance. Exercise can also elicit high electrolyte losses through the sweating response, particularly in warm to hot conditions.