Preserving Cerebral Resilience Through Physical Exercise: An Insight into its Antagonizing Effects on Brain Aging
Work Out Regularly to Boost Brain Health and Reduce Dementia Risk
Evidence continues to pile up that regular aerobic exercise can preserve brain health and cognitive function, keeping dementia at bay, especially in older adults with mild memory and thinking issues. This is what a team of researchers from the University of Texas Southwestern Medical Center in Dallas discovered in their investigation.
The researchers believe their study is the first to measure aerobic capacity objectively to assess the relationship between white matter integrity, cognitive performance, and cardiorespiratory fitness in older individuals with mild cognitive impairment (MCI).
As first study author, Kan Ding (an assistant professor of neurology and neurotherapeutics), puts it, "This research supports the hypothesis that improving people's fitness may improve their brain health and slow down the aging process."
The team's findings were published in the Journal of Alzheimer's Disease.
Individuals with MCI experience memory and reasoning issues but are not serious enough to interfere with daily living or self-care. It's estimated that "15-20 percent of those aged 65 and older may have MCI."
VO2max Testing for Fitness Assessment
The exact causes of MCI are still unknown, although experts suspect that in some cases, it might stem from brain changes occurring early in the stages of Alzheimer's disease or other types of dementia. The factors that increase the risk of developing MCI are the same as those that raise the risk of dementia - such as advanced age, having conditions that increase the risk of cardiovascular disease, and having a family history of dementia.
MCI often leads to dementia, but not everyone with MCI will develop dementia. In some, it can revert to normal cognitive functioning or simply remain static. The study focused on individuals with amnestic MCI, which primarily affects memory and may result in difficulty recalling names, appointments, events, conversations, or other information.
The researchers recruited 81 participants, with an average age of 65. Of these, 55 were people with amnestic MCI, and 26 were healthy individuals without MCI (controls). The team assessed the participants' cardiorespiratory fitness by measuring their maximal oxygen uptake (VO2max) during an aerobic exercise test.
Fitness Level and White Matter Integrity
Forty-three of the participants were female. In addition to assessing their fitness levels, the participants completed memory and reasoning tests and underwent diffusion tensor imaging (DTI), a type of scan used to assess white matter fiber integrity in the brain.
White matter is comprised of millions of bundles of neural fibers that connect brain cells, allowing them to convey messages. DTI enables researchers to assess white matter integrity in specific brain regions.
The results showed that MCI patients and the healthy controls had no differences in global white matter fiber integrity and VO2max. However, a closer examination revealed that reduced fitness levels were associated with weaker white matter in some parts of the brain. This link "remained statistically significant after adjustment of age, sex, BMI, white matter lesion burden, and MCI status."
Aerobic Fitness and Brain Health
The study also found that, for the participants with MCI, DTI measurements from brain areas with low white matter integrity linked to poor aerobic fitness correlated with performance on memory and thinking tests. Thus, higher levels of aerobic fitness are linked to better integrity of the brain's white matter, which in turn is connected to better executive function performance in MCI patients.
Aerobic exercise is just one element of a broader approach to managing MCI and potentially reducing the risk of dementia. Other studies have demonstrated that messages are passed more efficiently between brain cells in seniors who exercise, while other research indicates that aerobic exercise "may be key" for Alzheimer's prevention, and yet another finds that walking 4,000 steps per day can boost brain function.
"A lot of work remains to better understand and treat dementia," says Prof. Kan Ding. "But, eventually, the hope is that our studies will convince people to exercise more."
- The study by the researchers from the University of Texas Southwestern Medical Center found a connection between aerobic fitness and brain health, suggesting that improving fitness may slow down the aging process and reduce the risk of dementia, particularly in individuals with mild cognitive impairment (MCI).
- The findings were published in the Journal of Alzheimer's Disease and indicated that reduced fitness levels were associated with weaker white matter in some parts of the brain, even after adjusting for factors like age, sex, BMI, and MCI status.
- The study focuses on individuals with amnestic MCI, a condition that primarily affects memory and may result in difficulty recalling names, appointments, events, conversations, or other information. Experts suspect that MCI might stem from brain changes occurring early in the stages of Alzheimer's disease or other types of dementia.
- Although the exact causes of MCI are still unknown, it's estimated that 15-20 percent of those aged 65 and older may have MCI. Aerobic exercise, along with other elements of a holistic approach to health and wellness, could potentially play a role in managing MCI and reducing the risk of dementia.
