In a study, elderly women who engaged in the most activity — for example, walking at least 6 hours per week — had a 20 percent decrease in risk of cognitive impairment compared to those who were inactive. they also demonstrated the cognitive functioning of someone three-years younger than their actual age. The findings were published in the Sept. 22, 2004, issue of the Journal of the American Medical Association. “Walking is a popular, accessible and inexpensive activity for older adults that appears to provide many health benefits. In addition to studies showing a reduced risk of heart disease, pulmonary disease and diabetes, a moderate level of walking also appeared to reduce the rate of cognitive decline in our study,” said lead author Jennifer Weuve of the Harvard School of Public Health. “What is most striking is that for older women who are able to engage in several hours per week of physical activity, their cognitive function seemed to be comparable to that of a woman several years younger.” Researchers analyzed the data from 18,766 U.S. women, aged 70 to 81 years, from the Nurses’ Health Study.