Objectively assessed physical activity and sedentary behavior and global cognitive function in older adults: a systematic review.

BACKGROUND: Both physical activity (PA) and sedentary behavior (SB) are important factors for healthy ageing. This systematic review aimed to determine the association of objectively assessed (instrumented) PA and SB with global cognitive function in older adults. METHODS: PubMed, Embase, the Cochrane Library (via Wiley), CINAHL, PsychINFO, and SPORTDiscus (via EBSCO) were searched from inception to June 21, 2020 for articles that described associations of objectively assessed PA/SB with global cognitive function in older adults aged 60 years and older. Results were synthesized using an effect direction heat map and albatross plots portrayed estimated effect sizes (standardized regression coefficients (ßs)), which were summarized in boxplots. RESULTS: In total, 45 articles were included representing a total of 15,817 older adults (mean/median age ranged from 65 to 88 years; 49.5% female). Longitudinal studies (n = 7) showed that higher moderate-to-vigorous and light PA (MVPA and LPA, respectively) and lower SB were associated with better global cognitive function. Standardized ßs of cross-sectional studies (n = 38) showed that lower SB (median [IQR], ß = 0.078 [0.004-0.184] and higher LPA (ß = 0.096 [0.046-0.188]), activity counts (ß = 0.131 [0.049-0.224]), number of steps (ß = 0.155 [0.096-0.246]), MVPA (ß = 0.163 [0.069-0.285]) and total PA (TPA) (ß = 0.174 [0.147-0.255]) were associated with better global cognitive function. CONCLUSIONS: Higher PA and lower SB are associated with better global cognitive function in older adults. The greatest estimated effect sizes were found for moderate-to-vigorous and TPA, suggesting that greater duration of any PA, and high intensity PA could be most beneficial for global cognitive function.

The association of objectively measured physical activity and sedentary behavior with skeletal muscle strength and muscle power in older adults: A systematic review and meta-analysis.

BACKGROUND: Engaging in physical activity (PA) and avoiding sedentary behavior (SB) are important for healthy ageing with benefits including the mitigation of disability and mortality. Whether benefits extend to key determinants of disability and mortality, namely muscle strength and muscle power, is unclear. AIMS: This systematic review aimed to describe the association of objective measures of PA and SB with measures of skeletal muscle strength and muscle power in community-dwelling older adults. METHODS: Six databases were searched from their inception to June 21st, 2020 for articles reporting associations between objectively measured PA and SB and upper body or lower body muscle strength or muscle power in community dwelling adults aged 60 years and older. An overview of associations was visualized by effect direction heat maps, standardized effect sizes were estimated with albatross plots and summarized in box plots. Articles reporting adjusted standardized regression coefficients (ß) were included in meta-analyses. RESULTS: A total of 112 articles were included representing 43,796 individuals (range: 21 to 3726 per article) with a mean or median age from 61.0 to 88.0 years (mean 56.4 % female). Higher PA measures and lower SB were associated with better upper body muscle strength (hand grip strength), upper body muscle power (arm curl), lower body muscle strength, and lower body muscle power (chair stand test). Median standardized effect sizes were consistently larger for measures of PA and SB with lower compared to upper body muscle strength and muscle power. The meta-analyses of adjusted ß coefficients confirmed the associations between total PA (TPA), moderate-to-vigorous PA (MVPA) and light PA (LPA) with hand grip strength (ß = 0.041, ß = 0.057, and ß = 0.070, respectively, all p ≤ 0.001), and TPA and MVPA with chair stand test (ß = 0.199 and ß = 0.211, respectively, all p ≤ 0.001). CONCLUSIONS: Higher PA and lower SB are associated with greater skeletal muscle strength and muscle power, particularly with the chair stand test.