Physical activity predicts gray matter volume in late adulthood: the Cardiovascular Health Study

Area of Science:

• Neuroscience
• Gerontology
• Public Health

Background:

• Physical activity (PA) is hypothesized to preserve gray matter volume in aging brains.
• Longitudinal evidence directly linking PA to gray matter volume preservation has been limited.

Purpose of the Study:

• To investigate the association between PA and gray matter volume over a 9-year period.
• To determine a threshold for walking necessary to spare gray matter volume.
• To examine if preserved gray matter volume is associated with reduced cognitive impairment risk.

Main Methods:

• The study analyzed 299 older adults (mean age 78) from the Cardiovascular Health Cognition Study.
• Physical activity was measured by weekly blocks walked.
• Brain scans were conducted 9 years post-PA assessment, with cognitive impairment adjudicated 13 years post-baseline, controlling for covariates.

Main Results:

• Higher levels of physical activity (walking) were associated with greater gray matter volumes in frontal, occipital, entorhinal, and hippocampal regions.
• A minimum of 72 blocks walked weekly was required to observe increased gray matter volume, with no additional benefit beyond this threshold.
• Greater gray matter volume, linked to PA, showed a 2-fold reduction in the risk of cognitive impairment.

Conclusions:

• Increased walking is associated with greater gray matter volume in late adulthood.
• Preserved gray matter volume through physical activity is linked to a reduced risk of cognitive impairment.