These researchers found that, aerobic exercise training reverses hippocampal volume loss in late adulthood, which results in improved memory function. Shrinkage of the hippocampus in later adulthood is what leads to loss of memory and an increased risk of dementia.
For this study, the researchers recruited 120 older adults with a sedentary lifestyle and no signs of dementia and assigned them to two groups. One group walked around a track for 40 minutes a day, three days a week, while the second group did stretching and toning exercises. At the beginning, during the middle, and at the end of the year both groups underwent MRI brain scans, spatial memory tests, and gave blood samples. The researchers found that the group who underwent aerobic exercised had an increase in the size of the anterior hippocampus, which resulted in improved special memory.
According to the lead author of the study, Dr. Art Kramer, what is so significant about these results is that even a small amount of exercise makes a signifigant different to memory and brain health in sedentary older people. Dr. Kramer said, "Such improvements have important implications for the health of our citizens and the expanding population of older adults worldwide."
"Exercise training increases size of hippocampus and improves memory."
Kirk I. Erickson, Michelle W. Voss, Ruchika Shaurya Prakash, Chandramallika Basak, Amanda Szabo, Laura Chaddock, Jennifer S. Kim, Susie Heo, Heloisa Alves, Siobhan M. White, Thomas R. Wojcicki, Emily Mailey, Victoria J. Vieira, Stephen A. Martin, Brandt D. Pence, Jeffrey A. Woods, Edward McAuley, and Arthur F. Kramer.
PNAS, published ahead of print 31 January 2011.