The Association Between Physical Activity and Cognition in a Racially/Ethnically Diverse Cohort of Older Adults: Results From the Kaiser Healthy Aging and Diverse Life Experiences Study.

OBJECTIVE: Most prior research on physical activity (PA) and cognition is based on predominantly white cohorts and focused on associations of PA with mean (average) cognition versus the distribution of cognition. Quantile regression offers a novel way to quantify how PA affects cognition across the entire distribution. METHODS: The Kaiser Healthy Aging and Diverse Life Experiences study includes 30% white, 19% black, 25% Asian, and 26% Latinx adults age 65+ living in Northern California (n = 1600). The frequency of light or heavy PA was summarized as 2 continuous variables. Outcomes were z-scored executive function, semantic memory, and verbal episodic memory. We tested associations of PA with mean cognition using linear regression and used quantile regression to estimate the association of PA with the 10th-90th percentiles of cognitive scores. RESULTS: Higher levels of PA were associated with higher mean semantic memory (b = 0.10; 95% CI: 0.06, 0.14) and executive function (b = 0.05; 95% CI: 0.01, 0.09). Associations of PA across all 3 cognitive domains were stronger at low quantiles of cognition. CONCLUSION: PA is associated with cognition in this racially/ethnically diverse sample and may have larger benefits for individuals with low cognitive scores, who are most vulnerable to dementia.

Exercise training modifies the whole blood DNA methylation profile in middle-aged and older women.

This is a longitudinal single-arm clinical trial aimed to investigate whether exercise training would modify the whole blood methylation profile in healthy women. A total of 45 subjects were engaged in an exercise training protocol during a 14-wk follow up, consisting of aerobic cardiorespiratory and muscle strength exercises. Subjects were evaluated at baseline (PRE), after 7 wk of exercise training (POST 7), and after 14 wk of exercise training (POST 14). Functional primary outcomes included anthropometric, blood pressure, biochemical measurements, physical tests, and global health assessments. Blood samples were collected at each time point to determine the methylation profile using a DNA methylation array technique screening up to 850k different sites. Exercise training decreased blood pressure and triglyceride levels and enhanced physical performance, including upper- and lower-body maximum strength. Moreover, exercise training improved markers of quality of life. In the array analysis, 14 wk of exercise training changed the methylation of more than 800 sites. Across these differentially methylated sites, we found that differentially methylated sites in the promoter region were more hypermethylated after exercise training, suggesting that this hypermethylation process may affect the transcription process. When inputting the differentially methylated sites in pathway analysis, we found several metabolic pathways, including AMPK signaling, TGF-ß signaling, and insulin signaling. This study demonstrates that exercise training promotes a robust change in the whole blood methylation profile and provides new insights into the key regulators of exercise-induced benefits.NEW & NOTEWORTHY We have shown that exercise training lowers blood pressure and triglyceride levels, improves physical performance, and improves quality of life in middle-aged and elderly women. Regarding epigenetic data, we noticed that more than 800 sites are differentially methylated in whole blood after physical training. We emphasize that the differentially methylated sites in the promoter region are more hypermethylated after physical training. In addition, this study shows that key members of metabolic pathways, including AMPK signaling, TGF-ß signaling, and insulin signaling, are among the genes hypermethylated after physical exercise in older women.