Walking may slow Alzheimer's brain effects

CHICAGO, Nov. 29 (UPI) -- Walking may help slow Alzheimer's disease progression and slow cognitive decline in healthy adults as well, a U.S. researcher says.

Cyrus Raji of the University of Pittsburgh in Pennsylvania and colleagues conducted a study linking greater amounts of physical activity with greater brain volume. The researchers say cognitively impaired people needed to walk at least 58 city blocks -- approximately 5 miles -- per week to maintain brain volume and slow cognitive decline.

Healthy adults needed to walk at least 72 city blocks -- or 6 miles -- per week to maintain brain volume and significantly reduce their risk for cognitive decline.

"We found that walking 5 miles per week protects the brain structure over 10 years in people with Alzheimer's and mild cognitive impairment, especially in areas of the brain's key memory and learning centers," Raji says in a statement. "We also found that these people had a slower decline in memory loss over five years."

Raji and colleagues looked at physical activity and brain structure on 426 adults -- 299 healthy adults with a mean age of 78 and 127 cognitively impaired adults with a mean age of 81.

The findings of the 20-year study were presented at the annual meeting of the Radiological Association of North America in Chicago.