Influences of Aerobic Exercise on Motor Sequence Learning and Corticomotor Excitability in People With Parkinson’s Disease

Abstract

Background People with Parkinson’s disease (PD) are known to have motor learning difficulties. Although numerous studies have demonstrated that a single bout of aerobic exercise (AEX) can facilitate motor learning in non-disabled adults, the same beneficial effect in PD is unknown. Furthermore, associated neuroplastic changes have not been investigated. Objectives This study aimed to determine whether a single bout of aerobic exercise (AEX) can facilitate motor sequence learning in people with PD and to investigate the associated neurophysiological changes. Methods Thirty individuals with PD were recruited and randomized into the exercise group (PD + AEX) and non-exercise group (PD − AEX). At the first visit, corticomotor excitability was assessed using transcranial magnetic stimulation (TMS). All participants then performed a serial reaction time task (SRTT) followed by 20 minutes of moderately-high intensity aerobic exercise (AEX) for the PD + AEX group or rest for the PD − AEX group. The SRTT and TMS were reevaluated at 3 time points: immediately after aerobic exercise (AEX) or rest, on the second day after practice (D2), and a week after practice (D7). Results Both groups showed improvement throughout practice. At retention, the PD + AEX group showed improved SRTT performance on D7 compared to D2 ( P = .001), while the PD − AEX group showed no change in performance. TMS results showed that the PD + AEX group had significantly higher corticomotor excitability than the PD − AEX group on D7. Conclusion A single session of aerobic exercise (AEX) could enhance motor sequence learning and induce neuroplastic changes. Clinicians can consider providing aerobic exercise (AEX) after motor task training for people with PD. Clinical registration: NCT04189887 (ClinicalTrials.gov).

High-intensity acute exercise impacts motor learning in healthy older adults

“…The differing results in the current study may relate to the use of high-intensity exercise, and a more cognitively complex motor task. The current findings also contrast with preliminary findings in clinical populations such as Parkinson’s disease, wherein exercise was found to have no impact on motor acquisition during serial reaction time 36 and whole-body balance tasks 35 , 36 . Notably these studies also utilised moderate intensity exercise protocols, rather than high-intensity as in the current study.…”

“…This may relate to the cascade of neurochemical changes induced by high-intensity exercise, which may maintain an interval environment favourable for memory consolidation, including increased circulation of catecholamines 69 , lactate 70 , and brain-derived neurotrophic factor (BDNF) 71 . Notably, studies involving participants with Parkinson’s disease have shown motor learning improvements following moderate intensity exercise 35 , 36 . Individuals with age-related neurodegenerative disorders may demonstrate benefits from exercise on motor learning at a lower intensity compared to healthy older adults, due to the impact of exercise on disease related processes 72 .…”

“…Exercise intensity appears to be of particular importance, as greater benefits have been identified following high-intensity exercise (76-95% Maximal heart rate) compared to moderate (64-75% maximal heart rate) or light intensity exercise (57-63% maximal heart rate) [32][33][34] . In addition to healthy young adults, there is emerging evidence that exercise can improve motor learning in clinical populations such as Parkinson's disease 35,36 , and Huntington's disease 37 however this represents a relatively new area of research, and few large-scale studies have been conducted within these populations. Similarly, research into the benefits of acute exercise on motor learning in healthy older adults is limited.…”