• Posted December 12, 2024

Staying Fit Can Keep Seniors' Brains Sharp

Seniors who want to stay sharp as they age should hit the treadmill, elliptical or exercise bike as often as possible.

A new study shows that better cardio fitness in older age is linked to healthier brain aging.

That sort of fitness preserves brain health as people age even if they carry genetic risk factors that make them vulnerable to Alzheimer’s disease, researchers reported Dec. 10 in the British Journal of Sports Medicine.

“We found that cardiorespiratory fitness, which predicts the onset of numerous diseases and can be modified by regular exercise, was positively associated with cognitive performance across all domains assessed,” concluded the research team led by Kirk Erickson, director of translational research at AdventHealth Research Institute in Orlando, Fla.

For the study, researchers recruited nearly 650 brain-healthy seniors ages 65 to 80 and tested their cardio fitness using a graded treadmill running test.

Their brain power was also assessed with a comprehensive battery of tests carried out over two days.

Previous research has linked cardio fitness to a reduced risk of age-related brain decline and dementia, but it’s not clear which aspects of brain function cardio specifically boosts, researchers said in background notes.

The cognitive tests assessed five different types of brain function. These included processing speed, short-term working memory, long-term episodic memory, planning and organizational skills and the ability to interpret visual and spatial relationships.

As expected, people performed more poorly in all five areas as they got older, one researcher said.

But the results showed those with better cardio fitness performed more ably across all the domains of brain function than those with worse fitness. This benefit was irrespective of their age and whether they carried the APOE4 gene, which dramatically increases risk of Alzheimer’s.

The link between cardio fitness and brain function was greater in women than in men in the areas of processing speed and planning skills, researchers found. This also was true for people with fewer years of education and those taking beta blockers for high blood pressure.

The fact that cardio fitness benefitted people with less education supports the notion that exercise can protect against Alzheimer’s, since fewer years of education has been linked to greater risk of brain decline and dementia, the report shows.

“These findings, if replicated, suggest that the presence of one protective factor [eg, higher cardiorespiratory fitness] could attenuate the lack of another [eg, few years of education],” the researchers wrote.

Fitness might boost brain health by improving blood flow to the brain, prompting the growth of fresh neurons and new connections, and enhancing brain chemical systems, the researchers speculated.

Other factors linked to cardio fitness like improved mood, less fatigue and better sleep might also help protect brain health.

“These data emphasize cardiorespiratory fitness as an important health factor and therapeutic target for preserving multi-domain cognitive functioning in late adulthood,” the researchers concluded.

More information

The Cleveland Clinic has more on exercise and brain health.

SOURCE: BMJ Group, news release, Dec. 10, 2024