can a walk a day keep dementia at bay?
walking may help strengthen connections between brain networks, including those implicated in cognitive functioning and alzheimer’s disease.
3 minute read
previous research found when older adults with mild impairment walk regularly, they may experience enhanced brain function.
getty
a small study has found that walking does a world of good for aging brains by strengthening the connections inside and across three key networks, including one implicated in the occurrence of alzheimer’s disease.
the research, published in the journal for alzheimer’s disease reports, analyzed the brain structure and recollection ability of 33 adults with an average age of 78. some of the participant had normal brain function and others had been diagnosed with mild cognitive impairment. subjects in the latter group were experiencing early symptoms of mental decline, including issues with memory, reasoning and judgment.
“historically, the brain networks we studied in this research show deterioration over time in people with mild cognitive impairment and alzheimer’s disease,” said j. carson smith, principal investigator of the study and a kinesiology professor at the university of maryland school of public health. “they become disconnected and, as a result, people lose their ability to think clearly and remember things. we’re demonstrating that exercise training strengthens these connections.”
alzheimer’s disease is the most common cause of dementia in the world, accounting for 60 to 80 per cent of all cases, according to the alzheimer’s association. more than 747,000 canadians are currently living with the disease or another form of dementia. roughly 65 per cent of people diagnosed with the disease after the age of 65 are women.
advertisement
previous work by smith found that older adults with mild impairment who walk regularly may experience a decrease in cerebral blood flow and enhanced brain function. following up on these findings, the researcher recruited another 33 subjects, between the ages of 71 and 85, and supervised them as they walked on a treadmill four days a week for 12 weeks. before and after stepping on the treadmill, participants were required to read a short story to themselves and then repeat it out loud for researchers while trying to remember as many details as possible.
the group was also given a functional magnetic resonance imaging (fmri), which gave researchers a better look at the interplay between the three key brain networks controlling cognitive function:
the default mode network — an area connected to hippocampus that activates when the brain isn’t actively engaged in a task. this network, which is associated with daydreaming, is one of the first areas affected by alzheimer’s and where the amyloid plaques associated with the disease are found
the frontoparietal network — this area is plays a role in decision-making and also holds implications for working memory, problem-solving and executive functioning.
advertisement
the salience network — this area is thought to play a role in detecting and co-ordinating the brain’s response to behaviourally relevant stimuli. it helps the brain toggle between networks
by the end of the study, the team witnessed a significant improvement in the ability of subjects to recall details of the stories they read. they also detected stronger activity within the default and salience networks and stronger connections between all three networks.
“the brain activity was stronger and more synchronized, demonstrating exercise actually can induce the brain’s ability to change and adapt,” smith said. “these results provide even more hope that exercise may be useful as a way to prevent or help stabilize people with mild cognitive impairment and maybe, over the long term, delay their conversion to alzheimer’s dementia.”
dave yasvinski is a writer with healthing.ca
thank you for your support. if you liked this story, please send it to a friend. every share counts.
share story
