Posted on Dec 14, 2010, 6 a.m.
Walking may slow cognitive decline in adults with mild cognitive impairment (MCI) and Alzheimer's disease, as well as in healthy adults.
Alzheimer's Disease is a severe neurodegenerative disorder of the brain that is characterized by loss of memory and cognitive decline. Mild cognitive impairment (MCI) is a condition where a person has cognitive or memory problems exceeding typical age-related memory loss, but not yet as severe as those found in Alzheimer's disease; about half of the people with MCI progress to Alzheimer's disease. Cyrus Raji, from the University of Pittsburgh (Pennsylvania, USA), and colleagues have published data from an ongoing 20-year study of 299 healthy adults (mean age 78), and 127 cognitively impaired adults (mean age 81), including 83 adults with MCI and 44 adults with Alzheimer's dementia. The researchers monitored how far each of the patients walked in a week. After 10 years, all patients underwent 3D MRI exams to identify changes in brain volume. In addition, patients were given the mini-mental state exam (MMSE) to track cognitive decline over five years. Physical activity levels were correlated with MRI and MMSE results. The analysis adjusted for age, gender, body fat composition, head size, education and other factors. The findings showed across the board that greater amounts of physical activity were associated with greater brain volume. Cognitively impaired people needed to walk at least 58 city blocks, or approximately five miles, per week to maintain brain volume and slow cognitive decline. The healthy adults needed to walk at least 72 city blocks, or six miles, per week to maintain brain volume and significantly reduce their risk for cognitive decline. The researchers conclude that: “These results demonstrate that walking at least 72 blocks in two-weeks protects against gray matter volume loss in late adulthood and reduces the risk of experiencing cognitive impairment 13-years later.”
Raji C., et al. “Physical Activity and Gray Matter Volume in Late Adulthood: The Cardiovascular Health Cognition Study” [SSA17-01].” Presented at the 96th Scientific Assembly & Annual Meeting of Radiological Society of North America (RSNA), Nov. 28, 2010.