The unique relation of physical activity to executive function...

PURPOSE: To determine whether physical activity participation was specifically and positively associated with executive function in older individuals after accounting for age, education, and IQ. METHODS: Participants were 120 healthy men (N = 38) and women (N = 82) aged 65-92 yr (mean = 78.9, SD = 5.8), who were free of depression and dementia (Beck Depression Inventory and Mini-Mental Status Exam, respectively), had above-average intelligence (mean = 118.1, SD = 9.4) as indexed by the Kaufman Brief Intelligence Test (K-BIT), and stable patterns of physical activity during a 3- to 5-yr period before the study. Participants completed the Yale Physical Activity Survey (YPAS) for older adults and the Stroop Color and Word Test to assess inhibitory executive function. RESULTS: Hierarchical regression analyses revealed that YPAS summary index scores explained a small, but significant amount of variance in Stroop color-word and interference scores (DeltaR2 = 2 and 4%, respectively) after accounting for intelligence and age. The YPAS index was unrelated to nonexecutive performance. CONCLUSIONS: The results support specificity of the physical activity/cognition relationship in older individuals. The results may be explained by additive benefit from participation in physical activity to the frontal lobe (i.e., beyond any benefits from cognitive stimulation), a region that mediates executive function and experiences accelerated age-related decline. In summary, habitual physical activity is positively related to executive performance in older men and women into the 10th decade.