['By aging, some functions in nervous system like spatial memory are reduced. It has been shown that short-time physical activity can improve memory but there is much less data on the long-term exercising. In the present study, the aim was to clarify the effect of regular long-term physical activity on spatial memory and learning of young and middle aged and older male Wistar rats.', 'Sixty 3 months old rats were randomly divided in six equal groups. Experimental groups were treadmill exercised at speed 22m/min for 1h 6 days per week, and the program lasted 3, 6 and 9 months, respectively. At the end of training period, spatial memory of rats was tested using Morris Water Maze.', 'Results indicated that regular physical activity significantly increased spatial memory (p<0.05) in young rats (6 months old) as compared to controls, but not in the older ones (9 and 12 months old). Nonetheless, spatial memory of these rats was significantly better than in younger ones in both groups (p<0.05).'] Does long-term regular exercise promote memory and learning in young but not in older rats?