Swimming Training Prevents Stress-Induced Spatial Memory Impairment by Reducing Neurodegenerative Changes in Hippocampus.

This study investigated the effects of swimming training (ST) on hippocampal structure, specifically glial fibrillary acidic protein (GFAP), dark neurons, and the thickness of the CA1 region and dentate gyrus (DG), as well as spatial memory performance in young male rats subjected to chronic stress (CS). Adult male Wistar rats were randomly assigned to five groups: swimming training (ST), chronic mild stress (CMS), chronic mild stress followed by swimming training (CS + ST), chronic mild stress followed by a recovery period (CS + recovery), and a control group with no exercise or stress intervention. Spatial memory was assessed using the Morris water maze (MWM). The findings revealed that the ST group exhibited the lowest levels of GFAP and dark neurons, as well as the highest thickness of the CA1 and DG regions and the best spatial memory performance. In the CS + ST group, ST reduced GFAP and dark neurons, increased the thickness of the CA1 and DG, and improved memory performance compared to the control and CS + recovery groups. The CS group had the highest levels of GFAP and dark neurons, alongside the thinnest CA1 and DG regions. Meanwhile, in the CS + recovery group, GFAP and the number of dark neurons were lower than in the CS group. In summary, ST reduced GFAP and the number of dark neurons in both stressed and nonstressed rats, with a more pronounced effect observed in nonstressed rats. Overall, ST improved stress-induced spatial memory performance and hippocampal morphology in young male rats.