Prior exposure to a running wheel and scheduled food attenuates polydipsia acquisition.

Groups of rats were given different histories before exposure to daily, 2-h fixed-interval (FI) 1-min food-schedule sessions with water available. In a previous study, a group with a history of chronic exposure to FI 1-min sessions without water subsequently had a reduced rate of acquisition and final level of schedule-induced polydipsia compared to a control group lacking this history. In the present study, groups with histories of chronic exposure to FI 1-min sessions and a concurrent running wheel were even more attenuated in their subsequent acquisition of polydipsia. Substitution of 5% ethanol for session water in the final phase produced a convergence in group intakes, except for a group which continued to have access to the running wheel. The ethanol intake of this group was relatively suppressed.