Exercise has been demonstrated to have positive effects on both the body and brain. The present study aimed to determine the behavioural and morphological consequence of low-intensity running. Rats were exercised on a treadmill for a total of 30 days, 30 min/day. Social interaction, locomotor activity and behaviour on an elevated plus maze were assessed post-treatment. Exercised animals demonstrated more passive interaction and less time not interacting than control animals that were not exercised. Conversely, locomotor and anxiety measures showed no effect of exercise. Analysis of brains demonstrated an increase in expression of parvalbumin immunoreactive neurons in the hippocampus localised to the CA1 and CA2/3 regions. These results demonstrate that low-intensity exercise leads to changes in social behaviour as well as neuroplastic morphological changes within the hippocampus.