The unique relation of physical activity to executive function in older men and women

To determine whether physical activity participation was specifically and positively associated with executive function in older individuals after accounting for age, education, and IQ.

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.

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.

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.