Forced Aerobic Exercise for Stroke Rehabilitation

The goal of this study is to determine the potential for forced aerobic exercise to augment the recovery of motor function in individuals with stroke. Current approaches to stroke rehabilitation involve intensive, therapist-directed task practice that is both expensive and in some cases, ineffective in fostering functional neuromotor recovery. The identification of a safe, cost-effective approach, such as forced aerobic exercise, to augment the recovery of function achieved through task practice while simultaneously decreasing the cardiovascular risk factors prevalent in stroke survivors would be significant to rehabilitation and stroke communities. Animal studies along with preliminary human data indicate a specific type of aerobic exercise (AE), forced aerobic exercise (FE), may be ideal in facilitating motor recovery associated with repetitive task practice (RTP). The hypothesis is that that deficits in afferent input and motor cortical output following stroke prevents patients from achieving and maintaining an exercise intensity that is sufficient for facilitating motor recovery; therefore, FE is needed to augment their voluntary efforts and achieve greater gains in recovery. In previous research, a safe lower extremity FE intervention was initially applied to individuals with Parkinson's disease and subsequently to individuals with stroke. Preliminary results indicate that those completing an 8-week FE intervention paired with an abbreviated session of RTP exhibited significantly greater improvement in Fugl-Meyer scores at end of treatment despite completing 40% fewer RTP repetitions, compared to those receiving voluntary-rate aerobic exercise (VE) and RTP and time-matched RTP only. Improvements in cardiovascular fitness and lower extremity motor function were also evident in both groups that engaged in aerobic exercise (FE and VE). Positive results from a preliminary trial indicate safety, feasibility, and initial efficacy of combining two modes of aerobic exercise training with RTP provide rationale for a systematic and larger scale trial to determine the precise role of aerobic exercise, forced and voluntary, in facilitating motor recovery following stroke. For this study, 30 individuals with chronic stroke will be randomized into one of the following groups: FE = RTP, VE + RTP or patient education and RTP. All three groups will receive an identical dose of contact time over 8 weeks (3X per week). An intervention group receiving a 45-minute session of patient education paired with RTP will serve as the non-exercise control. Clinical and biomechanical outcomes measuring change in upper extremity motor function, lower extremity motor function, and cardiovascular fitness will provide the most complete picture, to date, on the potential neurologic effects of AE (forced and voluntary) on motor recovery and brain function in humans with stroke.