Efficacy of simultaneous aerobic exercise and cognitive training in subjective cognitive decline: study protocol for randomized controlled trial of the Exergames Study

Background: Subjective cognitive decline (SCD) is an early manifestation of Alzheimer’s disease (AD) and offers a therapeutic window where interventions have strong potential to prevent or delay the progression of AD. Aerobic exercise and cognitive training represent two promising interventions for AD prevention, but their synergistic effect has yet to be assessed in persons with SCD. Methods/design: The purpose of this single-blinded, 3-parallel group randomized controlled trial is to test the synergistic efficacy of an exergame intervention (simultaneous moderate-intensity aerobic cycling and cognitive training) on cognition and aerobic fitness in community-dwelling older adults with SCD. The Exergames Study will randomize 96 participants on a 2:1:1 allocation ratio to 3-month exergame, cycling only, or attention control (stretching). Primary outcomes include global cognition and aerobic fitness, which will be assessed at baseline and after 3 months. The specific aims of the Exergames Study are to (1) determine the efficacy of the exergame in older adults with SCD and (2) assess the distraction effect of exergame on aerobic fitness. Data will be analyzed using ANOVA following intention-to-treat. Discussion: This study will test the synergistic effects of exergame on cognition and aerobic fitness. It has the potential to advance prevention research for AD by providing effect-size estimates for future trials. Trial registration: ClinicalTrials.gov NCT04311736. Registered on 17 March 2020.