Regular Physical Activity Linked to Larger Brain Volume

Engaging in regular physical activity is associated with increased brain volume in critical areas, including gray and white matter and the hippocampus, according to recent research.

Study Overview:

• Objective: To explore the neuroprotective effects of regular physical activity on brain structure, addressing the unclear relationship between exercise and reduced dementia risk.
• Method: Researchers analyzed MRI brain scans from 10,125 healthy adults (average age 53; 52% male) who self-reported their physical activity levels. Moderate to vigorous physical activities—those elevating respiration and pulse for at least 10 continuous minutes—were examined in relation to brain volumes, with adjustments for various factors. The threshold for being considered physically active was set at 2.5 days per week, lower than current guidelines.
  
  Key Findings:
  
• Approximately 75% of participants engaged in moderate to vigorous physical activity about four days per week.
• After adjusting for multiple factors, an increase in days of moderate to vigorous activity correlated with larger normalized brain volumes in several regions, including total gray matter, white matter, hippocampus, and the frontal, parietal, and occipital lobes.
  
  Practical Implications:
  
• Co-author Dr. David Merrill from the Pacific Brain Health Center in Santa Monica, California, stated, “We found that even moderate levels of physical activity, such as taking fewer than 4,000 steps a day, can have a positive effect on brain health. This is much less than the often-suggested 10,000 steps, making it a more achievable goal for many people.”
  
  Limitations:
  
• Participants self-reported their physical activity over the past two weeks, which may not reflect lifetime activity levels.
• The observed correlation between physical activity and brain volumes may not be solely attributable to physical activity.
  
  Source:
  
  The study, led by Dr. Cyrus A. Raji from Washington University School of Medicine in St. Louis, was published online on December 7 in the Journal of Alzheimer’s Disease.

Print PDF