Relationships Among Physical Activity, Functional Fitness, and Cognitive Task Performance in Adults with Down Syndrome.

Physical activity (PA) and functional fitness (FF) are associated with cognitive task performance in the general population; however, such relationships remain understudied in adults with Down syndrome (DS). The purpose of this study was to examine associations among moderate-to-vigorous PA (MVPA), FF, and cognitive task performance, and explore whether FF may statistically account for associations between MVPA and cognitive task performance. Thirty-seven adults with DS (35 ± 10 years) completed the Timed-Up-and-Go (TUG) and handgrip strength (HGS) tests to assess FF, and the Eriksen Flanker Task (FT) to assess cognitive task performance. MVPA was measured by an accelerometer device over 7 days. Pearson's correlation indicated that MVPA was significantly associated with TUG (r = -.52, p < .001) and the Flanker effect (r = -.32, p = .047). TUG was associated with FT accuracy (r = -.44, p = .006) and Flanker effect (r = .33, p = .048). Exploratory mediation analysis suggested that TUG performance may partly explain an indirect association between MVPA and FT accuracy, with higher MVPA associated with better FF (i.e. lower TUG time) (β = -.48, p = .003), and better FF was also associated with greater FT accuracy (β = -.52, p = .008). Both MVPA and FF are associated with components of cognitive task performance in adults with DS. Mobility‑related FF showed an exploratory indirect association between MVPA and FT accuracy, suggesting that FF may represent a potential pattern of associations among PA and components of cognitive task performance in this population.