A six-month exercise program improves executive control in persons in the prodromal stages of Alzheimer's disease: Short- and long-term benefits


Older adults with memory complaints and/or objective cognitive deficits exhibit milestones for progression to dementia – a finding drawing attention to the need to develop intervention strategies that ameliorate further cognitive decline. The present work involved a large sample of individuals meeting the definition of a subjective cognitive complaint (Scc) who participated in a 24-week aerobic/resistance training (multi-modality group: M2) and aerobic/resistance with cognitive training (multi-modality, mind-motor group: M4) program. Each group completed three one-hour exercise sessions per week over the course of the training program and it is notable that the mind-motor group's training included a cognitively challenging task (i.e., square-stepping program) – a manipulation used to determine whether exercise in addition to cognitive training imparts an enhanced benefit to brain health than aerobic/resistance training alone. To determine whether the aforementioned programs improved executive control we contrasted pre-exercise antisaccade performance (i.e., saccade mirror-symmetrical to a target) with an immediate post-exercise time point, and again at a 28-week washout evaluation (i.e., without study-based intervention). Results showed that immediate and six-month post-exercise antisaccade reaction times for M2 and M4 groups were shorter than their respective pre-exercise performance, and that the magnitude of the executive benefit did not vary across groups. Thus, multi-modality exercise training improved executive control in persons with Scc regardless of the inclusion of cognitive training and this benefit persisted up to 28-weeks post-exercise. The washout results may reflect carryover benefits of the training program or an unanticipated increase in leisure time recreation activities.

Acknowledgments: Supported by NSERC and CIHR.