Priming the Rehabilitation Engine: Aerobic Exercise as the Fuel to Spark Behavioral Improvements in Stroke

Stroke is a leading cause of disability in the United States and poses a significant burden to Veterans. The effectiveness of current intervention approaches is limited and many individuals following stroke live with persistent functional, cognitive and psychological impairments that significantly reduce long-term quality of life.

The prevalence of post-stroke disability coupled with reduced stroke mortality rates reflects an increasing need to develop effective rehabilitation strategies aimed at reducing disability and improving quality of life for Veteran stroke survivors. Aerobic exercise (AEx) promotes numerous functional, cognitive, and psychological benefits.

Additionally, AEx may enhance neuroplasticity through increases in circulating brain-derived neurotrophic factor (BDNF) and corticomotor excitability (CME). Emerging evidence also supports the use of AEx as a priming tool to enhance motor outcomes following targeted rehabilitation. Our conceptual framework involves priming with

AEx prior to targeted motor rehabilitation to enhance the ‘neuroplastic environment” and make the brain more amenable to adaptation, thereby enhancing response to rehabilitation. Specifically, we propose to pair AEx with an upper extremity virtual reality rehabilitation game called Duck Duck Punch (DDP), developed by our team

(Co-mentor: Woodbury) as the platform for examining the adjunctive potential of AEx. Therefore the primary aim of this proposal is to evaluate the priming effects of AEx on a motor rehabilitation intervention (i.e. DDP) for chronic stroke survivors. This will be accomplished by examining a cohort of stroke survivors who

will be randomly assigned to receive 8 weeks (3 sessions/week) of DDP preceded by either 15 minutes of AEx (AEx+DDP) or a stretching control (CON+DDP). Assessment of physical function before and after the intervention will provide insight into the ability of AEx to enhance the response to motor rehabilitation. The

secondary aim of this proposal is to gain insight into the mechanisms that underlie the priming effects of AEx through assessment of circulating BDNF and CME. Additionally, since stroke survivors often experience cognitive and psychological impairments we will also explore the influence of cognitive and psychological

function on response to AEx+DDP. A potentially exciting possibility is that AEx facilitates an enhanced neuroplastic environment, which fosters improved function in a variety of aspects of stroke recovery including physical, cognitive, and psychological function. This proposal will be supported by the infrastructure and

resources provided by the South Carolina Research Center for Recovery from Stroke (NIH P20 GM109040). Furthermore, the combination of the Ralph H. Johnson VA Medical Center and its affiliated academic institution, Medical University of South Carolina is uniquely positioned to fill the aforementioned gap in understanding for

several reasons: 1) Charleston, South Carolina has one of the highest rates of stroke in the nation, and 2) in the last 5-years we have received over $23 million in research funds to support rehabilitation research in stroke recovery. During the award period, the applicant will capitalize on the opportunity to utilize these resources to

develop the requisite skills and understanding of neurobiological data acquisition, analysis, and interpretation through direct hands-on training from local renowned experts. The overall goal of this CDA-2 application is to expose the candidate to a rich local environment for stroke recovery research, providing the

foundation for his development into an independent VA researcher studying the effects of exercise- based interventions, alone or as adjuvants, for the treatment of Veterans. To accomplish this goal, the proposed training plan will enhance the candidate’s understanding of the neurobiological effects of AEx and the

design and delivery of neurorehabilitation trials. The data generated will inform the development of additional AEx-based interventions aimed at improving function and quality of life for individuals following stroke and perhaps other neurological or neuropsychiatric conditions.