Aerobic Exercise Stabilizes Motor Progression, Helps Cognition
Aerobic exercise stabilizes progression of motor symptoms and improves cognitive function in people with Parkinson’s disease, according to additional data from the Park-in-Shape clinical trial.
Notably, these benefits were found to be associated with increased neuronal connectivity in brain areas controlling such functions and with reduced brain atrophy (shrinkage).
These results add to previous findings from Park-in-Shape highlighting the benefits of aerobic exercise in Parkinson’s progression, and shed light on underlying brain changes.
The study, “Aerobic exercise alters brain function and structure in Parkinson’s disease a randomized controlled trial,” was published in the journal Annals of Neurology.
Increasing evidence points to a link between physical activity and brain health, with regular exercise helping to delay brain aging and neurodegenerative diseases such as Parkinson’s.
Notably, two independent clinical trials — SPARX (NCT01506479) in the U.S. and Park-in-Shape (NTR4743) in the Netherlands — have shown that aerobic exercise eases motor symptom progression in Parkinson’s disease. Other studies also suggested that exercise can lessen both motor and non-motor symptoms of Parkinson’s.
However, the underlying neural mechanisms of these benefits remain unclear.
To address this, researchers evaluated functional and structural brain changes in a subset of Park-in-Shape participants who also completed an additional cognitive control task.
Park-in-Shape involved 130 adults with mild Parkinson’s who were assigned randomly to undergo either 30- to 40-minute sessions of aerobic exercise in a stationary bicycle at home, or 30-minute sessions of stretching, flexibility, and relaxation exercises (active control), three times a week for six months.
Those in the aerobic exercise group were instructed to cycle at a target heart rate zone, which was increased gradually as the participants became fitter. All participants had a motivational app with tips for optimal training, support from loved ones, and information to track progress.
An unselected subset of participants — 25 in the aerobic exercise group and 31 in the active control group — underwent resting-state functional and structural magnetic resonance imaging, followed by a cognitive control task at the study’s start and at six months.
In this study, the researchers investigated how aerobic exercise influences brain function and structure, particularly at regions known to be involved in motor and cognitive functions and affected by Parkinson’s.
In terms of motor function, the team looked at changes in the cortico-striatal sensorimotor network that is involved in the emergence of motor deficits in Parkinson’s disease.
Previous studies showed that cortical sensorimotor regions that normally communicate with the posterior putamen in healthy individuals rely more on the anterior putamen in Parkinson’s patients. The putamen is a brain region involved in motor function control that forms part of the striatum, and its posterior portion is heavily affected in early Parkinson’s.
Results showed that aerobic exercise, but not stretching, led to a shift in cortico-striatal sensorimotor connectivity toward the anterior putamen, which is affected less by the disease.
An opposite increase in posterior putamen connectivity was detected in patients in the stretching group — the only Park-in-Shape group that showed motor symptom worsening after six months.
These findings suggest aerobic exercise may strengthen a compensatory brain mechanism that increases connectivity between cortical sensorimotor regions and the anterior putamen, and stabilizes motor function.
Six months of aerobic exercise also improved patients’ cognitive control, which was associated with increased functional connectivity between two brain networks involved in such function. Notably, greater increases in this network connectivity were associated with greater fitness improvements in these patients.
Moreover, patients undergoing aerobic exercise had significantly reduced global brain shrinkage relative to those in the stretching group.
Together with results from the Park-in-Shape study, these findings suggest that “aerobic exercise stabilizes motor progression and enhances cognitive performance in individuals with [Parkinson’s] by stimulating functional and structural plasticity in cortico-striatal sensorimotor and cognitive control networks,” the researchers wrote.
Neuroplasticity refers to the brain’s ability to make new connections in response to new information, stimulation, or development.
“Our study suggests that a viable alternative to influence clinical decline may be to focus on maintaining cortico-striatal sensorimotor function against disease progression and to strengthen compensatory cognitive processes,” the team wrote.
Larger studies are needed to confirm these findings.