Exercise as a Strategy for Enhancing Cognitive Health: A Meta-Analysis of Cerebral Blood Flow and Cognitive Function in Aging Populations (Preprint)

BACKGROUND The rapid global aging population has made cognitive decline in older adults a pressing public health challenge. Cognitive decline is closely linked to changes in cerebral blood flow, which is considered a critical physiological mechanism for delaying cognitive deterioration. However, the specific effects of exercise interventions on cerebral blood flow and their relationship to cognitive function remain inadequately understood. OBJECTIVE This study aims to systematically evaluate the effects of exercise interventions on cognitive function and cerebral blood flow in older adults through a comprehensive meta-analysis. By synthesizing data from multiple randomized controlled trials (RCTs) and controlled trials, this study seeks to provide precise and comprehensive evidence regarding the efficacy of exercise interventions in aging populations. Furthermore, the research aims to elucidate the relationship between cerebral blood flow and cognitive health, offering insights to inform the development of personalized exercise intervention strategies for maintaining cognitive health in older adults. METHODS Methods: A systematic meta-analysis was conducted, including studies published up to October 2024 from databases such as PubMed, Embase, and Web of Science. A total of 57 studies on cognitive function and 12 studies on cerebral blood flow were included, comprising randomized controlled trials (RCTs) or controlled trials. Rigorous quality assessments and data extraction were performed. Standardized mean differences (SMD) or weighted mean differences (WMD) with 95% confidence intervals (CIs) were calculated using random/fixed-effects models. Regression analysis was employed to investigate the relationship between cerebral blood flow and cognitive function. RESULTS Results: The meta-analysis revealed that exercise interventions significantly improved cognitive functions, including inhibitory control, switching function, memory, and verbal fluency in older adults. Exercise interventions also increased middle cerebral artery velocity (MCAv) and reduced resting heart rate and pulse index (PI). Regression analysis demonstrated that MCAv was positively correlated with overall cognitive function, memory, and verbal fluency but negatively correlated with inhibitory control. Conversely, heart rate and PI were negatively correlated with overall cognitive function and positively correlated with memory and inhibitory control. CONCLUSIONS Conclusion: Exercise interventions significantly enhance cognitive performance in older adults by improving cerebral blood flow and cardiovascular function. The increase in MCAv and changes in heart rate and PI play pivotal roles in the multidimensional effects of exercise on cognitive health. These findings support exercise as an effective strategy for delaying cognitive decline in aging populations and provide a theoretical foundation for developing personalized exercise programs. This study offers valuable insights for public health interventions targeting cognitive health in aging societies.