The association between sedentary behavior and cognitive ability in older adults

Executive functions (EF) are a grouping of cognitive abilities essential for daily life. Previous research has shown that physical activity (PA) may in fact preserve EF in older adults, but the link between sedentary behavior (SB) and cognitive ability has been less explored. The purpose of this study was to examine the relationship between SB and cognition (executive function and memory) in older adults. Seventy five older adults (74.6 +/- 9 years) self-reported their sedentary time (ST) and PA, as well as EF ability (paper-based measure of EF). Participants also completed several performance-based measures of EF and a memory task. Older adults who were less sedentary had superior EF and memory (e.g., Stroop time was significantly faster in less sedentary adults (34.7 s +/- 1.9) compared to more sedentary adults (39.6 s +/- 1.8), p = .02). Regression analysis showed that total ST was associated with several measures of EF after adjusting for age, and physical activity (e.g., Stroop time beta = .005 (.002, .009). Less cognitively demanding SB (TV viewing and napping) was associated with worse performance on most EF and in the memory task. Performing a hobby was also associated with lower levels of EF and memory. For example, the building times for the Lego task were positively related to napping (r(2) = .34), watching TV (r(2) = .27), and performing a hobby (r(2) = .46). Associations of ST with cognitive abilities were more pronounced in older adults who engaged in less PA. These results suggest that SB may play an important role in cognitive abilities of older adults. Longitudinal studies using performance-based assessments of EF are needed. Lara Coelho and Kayla Hauck contributed equally to the manuscript.