Background: Early recovery from stroke appears rapid and is at least partially underpinned by a time-limited period of heightened neuroplasticity. However, recovery often remains incomplete, with gains slowing in chronic stroke. Upregulation of neuroplasticity might help accelerate ongoing recovery in people with chronic stroke.
Aim: Investigate whether moderate intensity cardiovascular exercise could increase neuroplasticity in people with chronic stroke.
Methods: Thirty-three people with chronic stroke (aged 63.87 ± 10.30 years) participated in a randomised controlled trial. Participants were randomly allocated (1:1) to exercise or control. Those allocated to exercise completed 20 minutes of cycling at 60-80% heart rate max. The control group remained sedentary. Transcranial magnetic stimulation measured corticospinal excitability of the contralesional hemisphere by recording motor evoked potentials. Intermittent theta burst stimulation repetitively activate synapses in the contralesional motor cortex, initiating the early stages of neuroplasticity and increasing excitability. The hypothesis was that if exercise increased neuroplasticity, there would be a greater facilitation of corticospinal excitability following intermittent theta burst stimulation.
Results: Participants allocated to exercise had a stronger response to intermittent theta burst stimulation (Time*Group interaction P = 0.009). A non-significant trend indicated time since stroke might moderate this relationship (P = 0.055). Participants who were 2–7.5 years post stroke exhibited a much stronger intermittent theta burst stimulation response (P < 0.001). There was no effect of age, sex, lesion volume or weighted lesion load.
Conclusion: Moderate intensity cycling appears to enhance neuroplasticity in people with stroke. This therapy adjuvant could provide opportunities to maximize stroke recovery.