Forced-rate aerobic cycling enhances motor recovery in persons with chronic stroke: A randomized clinical trial

ABSTRACT Background: The potential for intensive aerobic exercise to enhance neuroplasticity post-stroke has been theorized but not systematically investigated. Our aim was to determine the effects of forced-rate aerobic exercise paired with an abbreviated session of upper extremity (UE) repetitive task practice (FE+RTP) compared to time-matched UE repetitive task practice (RTP only) on the recovery of motor function in individuals with chronic stroke. Methods: A single center randomized clinical trial was conducted from April 2019 to December 2022. Sixty individuals ≥6 months following single stroke with residual UE hemiparesis aged 18-85 were recruited. Participants were randomized 1:1 to one of two time-matched groups: FE+RTP (N=30) or RTP only (N=30). Both groups completed 90-minute sessions, 3x/week for 8 weeks. The FE+RTP group underwent 45-minutes of forced-rate aerobic exercise (FE) followed by 45-min of UE RTP. The RTP only group completed 2 sequential 45-minute sessions of UE RTP. The primary UE outcomes were the Fugl-Meyer Assessment (FMA) and the Action Research Arm Test (ARAT). The Six-minute Walk Test (6MWT) assessed walking capacity. Results: Sixty individuals 60.5 (±10.6) years of age and 26.0 [13.0, 69.0] months post-stroke were enrolled, and 56 completed the study. The RTP only group completed more RTP in terms of repetitions (411.8±44.4 versus 222.8±28.4, P<0.001) and time (72.7±6.7 versus 37.8±2.4 minutes, P<0.001) compared to FE+RTP. Both groups improved on the FMA (FE+RTP, 36.2±10.1 to 44.0±11.8 and RTP only, 34.4±11.0 to 41.2±13.4, P<0.001) and ARAT (FE+RTP, 32.5±16.6 to 37.7±17.9 and RTP only, 32.8±18.6 to 36.4±18.5, P<0.001). A group main effect was not observed. The FE+RTP group demonstrated greater improvements on the 6MWT (274.9±122.0 to 327.1±141.2 meters) compared to the RTP only group (285.5±160.3 to 316.9±170.0, P=0.004). Conclusions While both interventions elicited comparable improvements in UE motor recovery, the summative value of FE+RTP in improving UE and lower extremity function was demonstrated. Trial Registration: ClinicalTrials.gov NCT03819764