1220 GMT December 02, 2021
There’s currently no cure, but one study, published in the Neuro image: Clinical journal showed six months of strength training slowed and even halted the degeneration of the hippocampus and its subregions a year after the exercise, techiazi.com reported.
The University of Sydney study published in 2020 involved 100 participants at high risk of Alzheimer’s disease due to mild cognitive impairment — a decline in memory and other thinking skills, but daily skills still intact.
The participants were randomly split into four groups and given tasks including computerized brain training, strength training, a combination of the two and a control group.
Those doing strength exercises completed 90 minutes of supervised strength training (using dumbbells, weights or machines) each week for six months.
"They did that for 45 minutes, twice a week, for six months and then we waited for 12 months and that's when we saw these really strong effects,” explained senior author of the study Michael Valenzuela.
Professor Valenzuela, from the Brain and Mind Center, said it was the first time that any medical or lifestyle intervention had been shown to slow or halt degeneration in the brain over such a period.
"What we saw was a difference in terms of decline," he said.
"In the control group, those sub-parts of the hippocampus were shrinking at an expected level of around three to four percent.
"In those doing weight training, we saw much less, so one to two percent and in some areas none at all."
Professor Valenzuela was surprised by how clear the results were.
He continued: “There was no grey zone about these results.
“There was a clear difference in terms of brain anatomy and linked to that, those people doing strength exercises had far better cognitive outcomes than otherwise.
“These are not just structural changes, which are interesting for their own sake, they have a functional consequence.
“I do think it's very important and it's really pointing to the message that people hopefully have heard that exercise is good for the brain and the body but part of that exercise mix really should be strength training and lifting weights."
According to Professor Valenzuela there were two competing ideas of why strength training improved cognitive performance.
“One is the chemical idea which is pumping weights and doing exercise releases a whole myriad of chemicals into the bloodstream which are good for the body, good for anti-diabetes, they're good for anti-inflammatory," he said.
“Some might get into the brain and promote plasticity.
"The other idea is a central nervous system idea, which is that doing exercise repetitively stimulates almost electrically these memory parts of the hippocampus.
"We know this from rodents, we're not sure if this happens in humans."
Professor Valenzuela concluded there was a clear message that "resistance exercise needs to become a standard part of dementia risk-reduction strategies".
There’s no certain way to prevent all types of dementia, according to the NHS, as researchers are still investigating how the condition develops.
But the health body said there’s good evidence a healthy lifestyle can help reduce a person’s risk of developing dementia when they’re older.
It explained: “Experts agree that what's good for your heart is also good for your brain.
“This means you can help reduce your risk of dementia by eating a healthy, balanced diet, maintaining a healthy weight, exercising regularly, stop smoking, and keeping your blood pressure at a healthy level.”