A Systematic Review of Aerobic Exercise to Improve Cognitive Function in Older People Without Known Cognitive Impairment

AIMS: There is an increasing amount of evidence to suggest that regular physical exercise supports healthy ageing. Regular physical activity provides health benefits for the cardiovascular, respiratory and musculoskeletal systems as well as many other benefits. As well as improving cardiovascular fitness, aerobic activity in particular may also have beneficial effects on cognition among older people. In this paper, we aimed to systematically review the effect of aerobic physical activity, aimed at improving cardiorespiratory fitness, on cognitive function in older people without known cognitive impairment. METHODS: We searched the Cochrane Dementia and Cognitive Improvement Group's Specialized Register, the Cochrane Controlled Trials Register (CENTRAL), MEDLINE, EMBASE, PsycINFO, LILACS, World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (http://apps.who.int/trialsearch), ClinicalTrials.gov with no language restrictions. We included all published randomised controlled trials (RCTs) comparing the effect of aerobic physical activity programmes with any other active intervention or no intervention on cognitive function. Participants were ages over 55 with no known cognitive impairment. We looked at trials, which measured effects on both fitness and cognition. We reviewed the data from trials published since August 2013 to further the research completed by Young J, Angevaren M, Rusted J, Tabet N (published in 2015). This systematic review looked at all the studies completed before August 2013. RESULTS: There were a few trials that met our inclusion criteria. The aerobic activity programme that participants were subjected to varied in length. The comparison between aerobic exercise to any active intervention showed no evidence of benefit from aerobic exercise in cognition. None of our analyses showed a cognitive benefit from aerobic exercise despite the interventions demonstrating benefits to cardiorespiratory fitness CONCLUSION: The findings from the available data from the RCTs did not show any evidence that aerobic physical activities, including those which successfully improve cardiorespiratory fitness, have any cognitive benefit in cognitively healthy older adults. Larger studies with longer term interventions and longer follow up would be recommended.