Research Report
Population: Adult
Susan M Linder, PT, DPT, MHS, NCS, Research Scientist / Project Staff, Cleveland Clinic linders@ccf.org
Anson Rosenfeldt, DPT, MBA, NCS, Senior Physical Therapist, Cleveland Clinic rosenfa2@ccf.org
Tanujit Dey, PhD, Statistician/ Associate Staff, Cleveland Clinic deyt@ccf.org
Jay Alberts, PhD, Staff, Biomedical Engineering, Cleveland Clinic albertj@ccf.org
Keywords: Plasticity, Forced Exercise, Repetitive Task Practice, Neuroplasticity
Purpose/Hypothesis: Aerobic exercise (AE) training in individuals with stroke has been shown to improve cardiovascular function; however, the potential neuroplastic or neurorestorative role of AE in the stroke population has not been systematically studied. We sought to investigate the effects of two modes of AE training – forced exercise (FE) and voluntary exercise (VE) to determine if either mode of AE, when coupled with upper extremity (UE) repetitive task practice (RTP), resulted in greater improvements in motor recovery compared to time-matched RTP only. We hypothesized that individuals with stroke require augmentation to allow them to achieve and sustain an intensity of AE sufficient to harness its neuro-restorative properties. Therefore, we hypothesized that those who participated in FE+RTP would demonstrated greater improvements in UE motor recovery compared to VE+RTP or time-matched RTP only without an AE component.
Subjects: Seventeen individuals with UE paresis 6-12 months post-stroke
Materials/Methods: Participants were randomized into one of 3 groups: 1)FE+RTP (n=5), 2)VE+RTP (n=6), or 3)time-matched RTP only (n=5). Those in the FE and VE groups completed a 45-min session of stationary cycling at a forced rate (FE) or their voluntary rate (VE), followed immediately by a 45-min session of UE RTP. The RTP only group completed two 45-min sessions of RTP without an AE component. All participants attended 3 times per week for 8 weeks.
Results: Participants in the FE and VE groups demonstrated mean improvements of 12.3 and 4.8 points, respectively on the FMA from baseline to end of treatment, despite completing 40% fewer repetitions than the RTP only group, who demonstrated a mean improvement on the FMA of 4.4 points. Only the FE group’s improvements on FMA were significant. The FE and VE groups demonstrated mean improvements in Peak VO2 of 1.3 mL/kg/min and 2.4 mL/kg/min, respectively, while the RTP group demonstrated a decrease of -0.44mL/kg/min. Cadence was significantly higher for the FE group compared to VE, at 80.7 RPM and 67.2 RPM, respectively, while aerobic intensities as measured by percent heart rate reserve were similar at 56.5% and 55.9%, respectively.
Conclusion: AE training, when paired with an abbreviated session of RTP, may enhance the motor learning benefits associated with task practice while simultaneously improving cardiovascular fitness. Our FE approach, in which pedaling rate is augmented may be optimal over VE in potentially priming the brain for motor recovery.
Clinical Relevance: Physical therapists should consider including AE training as an approach to potentially prime the CNS for motor recovery following stroke, and couple it in close proximity to task practice to optimize motor recovery.
Citation:
Linder, Susan M, PT, DPT, MHS, NCS; Rosenfeldt, Anson B, DPT, MBA, NCS; Dey, Tanujit , PhD; Alberts, Jay L, PhD. Forced Aerobic Exercise Improves Motor Outcomes in Individuals with Stroke.. Poster Presentation. IV STEP Conference, American Physical Therapy Association, Columbus, OH, July 17, 2016. Online. https://u.osu.edu/ivstep/poster/abstracts/048_linder-et-al/