Exercise reverses memory loss
Moderate exercise increases the size of part of the brain that controls memory, researchers suggest
By Peter Russell
WebMD Health News, February 1, 2011
Reviewed by Dr Rob Hicks
Article Link: http://www.webmd.boots.com/healthy-ageing/news/20110201/exercise-reverses-memory-loss
1st February 2011 – Exercising for 40 minutes three times a week can boost memory in older people, a new study suggests.
Researchers in the US say a year’s worth of moderate physical activity was enough to increase the size of the brain’s hippocampus, leading to the improvement in spatial memory.
820,000 people in the UK have dementia, a number forecast to rise as our population ages. Although the study did not look at people with the condition, it could have important implications for an ageing society.
Teams led by scientists from the University of Pittsburgh and the University of Illinois recruited 120 inactive people aged between 55 and 80 without dementia and assigned them at random to two groups. Half began an exercise regime in which they walked around a track for 40 minutes a day, three times a week. The remainder acted as a ‘control’ group for the experiment and were limited to stretching and toning exercises.
Magnetic resonance images of the brains of all those taking part were collected before the experiments began, after six months and at the end of the one year study.
The researchers found that in the aerobic exercise group they were able to measure an increase in volume of the left and right hippocampus of 2.12% and 1.97%, respectively.
The same regions of the brain in those who did stretching exercises decreased in volume by 1.40 and 1.43 percent, respectively.
Reversing age-related loss
Writing in Proceedings of the National Academy of Sciences, the authors note that the size of the Hippocampus shrinks by 1-2% each year in older adults who do not have dementia, and that this loss of volume increases the risk of losing brain function. They write, “Exercise training increased hippocampal volume by 2%, effectively reversing age-related loss in volume by one to two years.”
Spatial memory tests were carried out on all participants at the three intervals. Those in the aerobic exercise group showed improved memory function, when measured against their performance at the start of the study, the researchers report.
"We think of the atrophy of the hippocampus in later life as almost inevitable," Kirk Erickson, professor of psychology at the University of Pittsburgh and the paper’s lead author said in a statement. "But we’ve shown that even moderate exercise for one year can increase the size of that structure. The brain at that stage remains modifiable."
Art Kramer from the University of Illinois, and lead author of the research, said in a statement: "The results of our study are particularly interesting in that they suggest that even modest amounts of exercise by sedentary older adults can lead to substantial improvements in memory and brain health."
Never too late to exercise: Dementia charity
Dr Simon Ridley, Head of Research at the Alzheimer’s Research Trust, said in an emailed statement: “Although this study doesn’t look at memory loss in Alzheimer’s or dementia, it suggests it’s never too late to start exercising to help keep our brains healthy. Even modest exercise may improve memory and help protect the brain from normal decline caused by ageing.”
“Increasing evidence suggests regular exercise and a healthy diet may help reduce our risk of developing dementia as well as reaping numerous other benefits from living a healthy lifestyle.”
Press release, University of Pittsburgh.
‘Exercise training increases size of hippocampus and improves memory’, Arthur F Kramer et al, Proceedings of the National Academy of Sciences, doi/10.1073/pnas.1015950108.
Dr Simons Ridley, Alzheimer’s Research Trust.
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