Aerobic Exercise May Slow Brain Shrinkage in People at High Risk for Alzheimer’s

Researchers at UT Southwestern Medical Center report that exercising several times every week may help slow undesirable brain changes, such as those linked to Alzheimer’s disease.

Aerobic Exercise

In the new study, it was found that aerobic exercise may offer more benefits for reducing brain atrophy in people at high risk of dementia than flexibility training.

Researchers observed that people with amyloid-beta buildup in their brains who did regular exercise for a year had reduced hippocampal atrophy. The hippocampus is a part of the brain necessary for memory.

A buildup of amyloid-beta in the brain has a connection to Alzheimer’s disease. Scientists have found that amyloid plaques seem to be responsible for neuronal death in the brains of people with dementia.

“What are you supposed to do if you have amyloid clumping together in the brain? Right now doctors can’t prescribe anything,” said lead researcher Rong Zhang.

While the exercise did not exactly prevent brain deterioration, it is notable that it helps to slow it.

Zhang, a professor at UT Southwestern, said that doctors will be recommending exercise more for people at high risk for dementia if their findings are replicated in a bigger trial. He also noted that there was nothing wrong if doctors have already started doing so.

Exercise and the brain

It is believed that more than 5 million people suffer from Alzheimer’s in the United States. The need to find effective treatments is increased by the prediction that the incidence of this disorder will triple in about three decades.

This is not the first time scientists will observe the beneficial effects of exercise on brain health. Zhang and his team seem to actually draw inspiration for this study from research showing similar results in mice.

In a study reported last year, researchers also found that individuals who were less-fit experienced a more rapid decline of white matter in their brains.

Some scientists, including Zhang and his colleagues, are now shifting their attention to exercise as a possible remedy for dementia. This is after billions of dollars already spent in search of a cure have failed to yield anything significant yet.

The recently-published study is the first randomized, controlled research to show how aerobic exercise may be more beneficial than other forms of exercise.

Shrinkage reduced

There were 70 sedentary subjects in the current study. These were 55 years of age or older and had mild amnestic mild cognitive impairment (aMCI), an early sign of Alzheimer’s.

The participants were divided into two groups. Subjects in a group performed aerobic exercise lasting a minimum of 30 minutes, four to five times a week, for a year. Those in the second group only did flexibility training (stretching and toning).

At the end of 12 months, both groups showed similar results in terms of cognitive abilities, such as memory and executive function. Individuals in the two groups still had amyloid buildup.

Brain imaging, however, showed that subjects in the aerobic exercise group who had amyloid buildup experienced less hippocampal deterioration, compared to those in the other group.

“It’s interesting that the brains of participants with amyloid responded more to the aerobic exercise than the others,” Zhang said.

Further research

The scientists noted that this was only a “proof-of-concept study,” so they could not draw definitive conclusions from it just yet.

Zhang stated that there was a need for further research to know more about if or how the reduction of brain atrophy can improve cognition.

The UT Southwestern professor leads a five-year clinical study involving over 600 at-risk subjects for Alzheimer’s whose ages fall between 60 and 85 years.

Researchers aim to understand the possible relationships between exercise and dementia in the trial. They will evaluate how aerobic exercise and certain medications may be useful for guarding against brain atrophy and decline in cognitive abilities.