A new study is the first to find a relationship between cardiovascular fitness and brain health in older adults.
Researchers discovered fitness levels improved the structure of white matter in older adults, a finding that suggests exercise could be a prescribed as a therapy to reduce age-related declines in brain structure.
Interestingly, investigators did not discover improvements in brain structure as related to cardiovascular fitness among younger adults.
The findings are found online in the Annals of Clinical and Translational Neurology.
For the study, researchers compared younger adults (age 18-31) to older adults (age 55-82). All participants had MRIs taken of their brains and their cardiorespiratory (heart and lung) fitness was measured while they exercised on a treadmill.
The researchers found cardiorespiratory fitness was positively linked to the structural integrity of white matter fiber bundles in the brain in the older adults, while no such association was observed in younger adults.
“We found that higher levels of cardiorespiratory fitness were associated with enhanced brain structure in older adults,” said corresponding author Scott Hayes, Ph.D., assistant professor of psychiatry at Boston University School of Medicine and the associate director of the Neuroimaging Research for Veterans Center at the VA Boston Healthcare System.
“We found that physical activities that enhance cardiorespiratory fitness, such as walking, are inexpensive, accessible, and could potentially improve quality of life by delaying cognitive decline and prolonging independent function,” he added.
According to the researchers, these results provide evidence of a positive association between fitness and brain structure in older adults.
“We hope this study provides additional motivation for older adults to increase their levels of physical activity, which positively impacts health, mood, cognition, and the brain.”
Nevertheless, researchers caution that additional research is needed before an accurate exercise prescription can be issued to improve brain structure.
For example, the impact of a specific type of exercise program — be it strength, aerobic, or combined training — on white matter needs to be determined. Researchers also need to define the appropriate exercise dose, in terms of frequency, intensity, duration, required to improve white matter microstructure.