Corticospinal excitability enhances when aerobic exercise matches regular physical activity intensity

Abstract

Corticospinal excitability (CSE) increases after a single bout of aerobic exercise (AE), facilitating neuroplasticity. However, while some individuals enhance in CSE after a bout of AE, others show a decrease or no apparent change. This variability may result from the AE intensity being improperly tailored to the intensity of one’s regular physical activity (RPA) behaviours. As such the objective of this research study was to determine the influence RPA behaviours have on facilitating CSE after a single bout of AE. The relationship between RPA intensity, assessed using accelerometers, and CSE, assessed using single-pulse transcranial magnetic stimulation, was examined at three different AE intensities (low, moderate, and high) to determine if there was a match between RPA intensity and AE intensity that leads to a change in CSE. We hypothesized greater CSE increases would result when the RPA intensity matched with the AE intensity. Results showed a positive relationship between time spent in vigorous physical activity and CSE, in that CSE increased to a greater extent after the bout of high intensity AE in those participants who spent a greater percentage of time doing vigorous physical activity. No such relationship was observed between time spent in moderate physical activity and CSE or time spent in low physical activity and CSE. These findings improve our understanding of the impact RPA behaviour has on the brain’s response to an acute bout of AE, and overall may help in advancing the individualized prescription of AE