Changes in the perceived pleasantness of fluids before and after fluid loss through exercise: a demonstration of the association between perceived pleasantness and physiological usefulness in everyday life.

It has previously been suggested that the perceived pleasantness of a food item in any situation may be directly related to the physiological usefulness of that item to the consumer in that situation. This study investigated changes in the perceived pleasantness of fluids before and after fluid loss through exercise-an everyday situation in which physiological need can alter. Total of 40 exercisers achieving high fluid loss (Group H) and 41 exercisers achieving low fluid loss (Group L) rated seven fluids of varying osmolality, electrolyte content, and energy content on measures of pleasantness, before and after exercise. After fluid loss compared to before fluid loss, perceived pleasantness of all fluids increased (F(1,79)=14.58, p<0.01), and effects were greater in Group H compared to Group L (F(1,79)=8.29, p<0.01). Perceived pleasantness was also significantly higher for fluids of lowest osmolality (F(6,474)=2.14, p<0.05), and effects were again greater in Group H compared to Group L (F(6,474)=2.10, p<0.05). Both findings suggest that perceived pleasantness is related to physiological usefulness, and can be demonstrated in everyday situations.