Associations between physical activity and sedentary behaviour patterns and cognition: A cross‐sectional analysis of the Canadian Longitudinal Study on Aging

Abstract Background Engaging in regular physical activity (PA) and limited sedentary behaviour (SB) are critical for healthy cognitive aging. However, it is unclear what combination of PA and SB patterns (e.g., high PA and low SB, high PA and high SB, etc.) is most beneficial for cognition. We thus examined how different combinations of PA and SB were associated with cognitive performance in community‐dwelling middle‐aged and older adults. Method A cross‐sectional analysis using baseline data from the Comprehensive cohort of the Canadian Longitudinal Study on Aging (CLSA; 2010‐2015) among participants with complete PA and SB data (n = 23,125; age range 45‐86 years). PA and SB were indexed using the Physical Activity Scale for the Elderly (PASE) and cognition using a three‐factor structural equation model (i.e., memory, executive function, and verbal fluency). Participants' PA and SB levels were classified as 1) low PA and high SB; 2) low PA and low SB; 3) high PA and high SB; and 4) high PA and low SB. Linear regressions assessed associations between PA and SB combinations and cognition, adjusted for age, sex, activities of daily living, income level, educational attainment, and depression. Contrasts with Bonferroni correction tested associations of combinations of PA and SB with cognition. Result High PA was associated with better cognition whether combined with low or high SB. A high PA and low SB combination was associated with better executive function (Estimated mean difference = ‐0.24, 95%CI ‐0.39 to ‐0.10, p< 0.001) and verbal fluency (Estimated mean difference = ‐0.29, 95%CI ‐0.42 to ‐0.16, p< 0.001) vs. low PA and low SB. A combination of high PA and high SB was associated with better executive function (Estimated mean difference = 0.17, 95%CI 0.01 to 0.33, p = 0.034) and verbal fluency (Estimated mean difference = 0.20, 95%CI 0.05 to 0.34, p = 0.002) vs. high PA and low SB. Surprisingly, low PA and high SB was associated with better executive function vs. low PA and low SB (Estimated mean difference = 0.26, 95%CI 0.11 to 0.41, p <0.001) (Table 1 and Figure 1). Conclusion High PA, irrespective of SB, is associated with better cognition. Low PA levels may be more detrimental to cognition than high SB levels.