At risk of Alzheimer's disease? Exercise could help keep him at bay

WEDNESDAY, July 17, 2019 (HealthDay News) – Even if you are at risk of contracting Alzheimer's disease, a little more exercise can save you time, according to new research.

People with high levels of a brain protein called beta-amyloid tend to be more likely to develop Alzheimer's disease and experience rapid brain decline later in life, revealed research. earlier.

But apparently, they can delay the onset of Alzheimer's disease by doing regular exercise, scientists report.

"People who had high levels of amyloid, one of the first changes seen in Alzheimer's disease, had lower rates of cognitive decline and loss of brain volume over time." they were doing more physical activity, "said lead researcher Jennifer Rabin. She is a scientist in the Hurvitz Brain Science Program at the Sunnybrook Research Institute in Toronto.

It did not take much exercise to benefit from this protection either.

The data suggest that people who walked between 8,300 and 8,900 steps a day significantly delayed the onset of Alzheimer's disease, Rabin said.

Previous studies have shown that older people who exercise tend to stay in shape longer, but this new research shows that physical activity is specifically protective for people with these early brain changes related to Alzheimer's disease, said Dr. Howard Fillit. He is Executive Director and Scientific Leader of the Alzheimer's Drug Discovery Foundation.

"This population is different from the one that was studied before because you are looking for clinically normal people but showing signs of Alzheimer's disease in their brains," said Fillit, who did not participate in the study. research.

For this study, Rabin and colleagues asked 182 participants in Harvard's brain aging study to wear a pedometer for a week to measure their usual level of physical activity. Brain scans have been used to detect beta-amyloid levels in their brains.

Beta-amyloid has a tendency to clump in the brain of patients with Alzheimer's disease, congregating in sticky plates between neurons and possibly disrupting the function of brain cells.

The researchers then followed the participants over a period of up to seven years, with annual tests to check the status of their brain functions. Repeated scans were also performed to see if their brains had begun to contract, which is a sign of Alzheimer's progression.

The study found that people who walked more tended to stay sharper and suffer a slower loss of brain volume.

What is remarkable is that the brain benefits of exercise were independent of the benefits to the health of the heart and blood vessels, Fillit said.

This means that physical activity helps the brain in a way that goes beyond the prevention of micro-stroke that can contribute to dementia, said Fillit and Rabin.

Physical activity could preserve brain function by reducing inflammation, improving the overall flow of blood to the brain, or helping people sleep better, Rabin said.

Exercise has also been badociated with higher levels of BDNF [brain-derived neurotrophic factor], a brain chemical that "is the most powerful neuroprotective growth factor we know," Fillit said.

"There is no need for training at the Tour de France level," said Fillit. "It can simply work from a treadmill or elliptical exerciser and get your heart rate up."

Rabin warned that, although physical activity apparently helps to alleviate amyloid-related brain function impairments, people with high levels of beta-amyloid are not likely to age as well as those with without amyloid in their brain.

But it is possible that if these people badociate exercise with heart-healthy habits, such as eating well and controlling their blood pressure, they could further reduce their risk of brain loss, Rabin added.

"If you go for a lot of good lifestyle choices, you might be able to get back to your normal aging path," said Rabin.

The results were published online July 16 in the journal JAMA Neurology and presented the same day at the International Conference of the Alzheimer Association in Los Angeles.

More information

The Alzheimer's Association has more on the prevention of Alzheimer's disease.