Abstract
OBJECTIVE: To determine how physical activity at various ages over the life course is associated with cognitive impairment in late life. DESIGN: Cross-sectional study. SETTING: Four U.S. sites. PARTICIPANTS: Nine thousand three hundred forty-four women aged 65 and older (mean 71.6) who self-reported teenage, age 30, age 50, and late-life physical activity. MEASUREMENTS: Logistic regression was used to determine the association between physical activity status at each age and likelihood of cognitive impairment (modified Mini-Mental State Examination (mMMSE) score >1.5 standard deviations below the mean, mMMSE score