Relations of Executive Function and Physical Performance in Middle Adulthood: A Prospective Investigation in African American and White Adults.

OBJECTIVES: Previous studies in older adults found robust associations between executive functions (EF) and physical performance, as well as sociodemographic variation in physical performance decline. To examine these associations earlier in the adult lifespan, we investigated relations of EF, race, and sex with age-related physical performance decline during middle adulthood.
METHOD: Participants were 2,084 urban-dwelling adults (57.2% female; 57.8% African American; 37.3% living in poverty; mean baseline age = 48.1) from the Healthy Aging in Neighborhoods of Diversity across the Life Span study. Mixed-effects regression was used to examine interactive relations among EF, race, sex, and age (indexing time) with change in dominant and nondominant handgrip strength and lower extremity strength over approximately 5 years. All analyses adjusted for poverty status, and subsequently adjusted for education, body mass index, hypertension, and diabetes.
RESULTS: There were no significant prospective associations between EF and decline in physical performance measures. Significant cross-sectional associations revealed that lower EF was associated with worse performance on all physical performance measures averaged across both time points (p < .05). A significant two-way interaction of Sex × Age (p = .019) revealed that men experienced greater age-related decline in lower extremity strength than women. DISCUSSION: Findings did not reveal prospective associations between EF and physical performance decline in middle adulthood. However, they identified robust cross-sectional associations between EF and physical performance, and unexpectedly greater decline in lower extremity strength in men than women. Ultimately, these findings may inform prevention and intervention strategies targeting groups at risk for poorer physical function status and decline.