Comparative Efficacy of Exercise Intensity on Cognitive Function for Older Adults with Cognitive Impairment: A Systematic Review with Meta-Analysis

Abstract

The incidence of mild cognitive impairment (MCI) and dementia is on the rise due to an ageing population, and there is currently a lack of pharmacological prospects in mitigating this risk. As a result of this, physical activity has been identified as a potential preventative and intervention measure for delaying or preventing cognitive impairment. This meta-analysis aims to explore the effect of high-intensity exercise and low- to moderateintensity exercise on cognition for older adults with a diagnosis of either MCI or dementia. A number of different online databases were searched, and 18 studies were identified as meeting all of the inclusion criteria for this meta-analysis. Results indicated that exercise significantly improves cognitive ability for older adults with cognitive impairment. Highintensity exercise did not have a significant effect on cognition, and higher frequency of high-intensity exercise led to poorer cognitive performance. Low- to moderate-intensity exercise did have a significant effect on cognition, and longer durations at this level of intensity leads to bePer cognitive outcomes. The results of the subgroup analyses indicates that the effect of exercise differs depending on the length of the intervention with shortterm interventions eliciting significant cognitive benefits but long-term interventions not having an effect. A diagnosis of MCI also leads to exercise having a larger effect than a diagnosis of dementia. This meta-analysis provides information that can help to inform best practice and further our understanding of what intensity of exercise elicits greater cognitive benefits for this population.