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Exercise may keep brain sharp in old age- 22-Sep-2014
The white matter is composed of fibre-like parts of brain cells that enable communication between brain regions.
Researchers at the University of Illinois studied 88 people between ages 60 and 78 who had low cardiovascular fitness but were otherwise healthy.
The participants wore accelerometers for a week to track their daily physical activity, as well as how much time they spent sitting.
The researchers examined the brain scans of the participants to look at how structurally sound the white matter was.
They looked for lesions called "white matter hyperintensities," which are common in older people, 'Live Science' reported.
The results showed that the more people engaged in moderate or vigorous exercise, the fewer white-matter lesions they had.
The findings suggest that increasing physical activity and avoiding a sedentary lifestyle could be beneficial for brain health, researchers said.
The researchers also found that light physical activities, such as housework and gardening, was related to how structurally sound people's white matter was in some parts of the brain.
The more people engaged in light physical activities, the more structurally sound their white matter was in the temporal lobe, a part of the brain that lies behind the ears and is involved in memory and language.
In contrast, the more time people spent sitting, the more they showed lower structural soundness in the white-matter tracts connecting the hippocampus, a brain area important for learning and memory.
The study was published in the journal PLOS ONE.
