Long periods of inactivity may lead to atrophy of the part of the brain
responsible for memory, according to a preliminary study from the University of
California, Los Angeles. Researchers surveyed 35 people between the ages of 45
and 75 who did not have dementia about their physical activity levels and the
average hours per day they spend sitting over a seven-day period. Participants
also underwent MRIs, which provided a high-resolution image of the medial
temporal lobe, the region of the brain involved in the formation of new
The researchers - who cited past research on the connection between physical
activity and the delay of the onset of dementia and Alzheimer's disease - found
that more sitting led to thinner medial temporal lobes, which can be an early
sign of cognitive decline and dementia in middle-aged and older adults. They
stress, however, that their findings do not prove that excessive sitting causes
thinner brain structures - only that increased sedentary time is associated
with thinner brain regions.
The researchers also concluded that physical activity, no matter the level,
does not compensate for the harm done by sitting for extended periods.
The study was published in the journal PLOS ONE.
AplusA-online.de - Source: safety and health magazine