Cortical and motor responses to acute forced exercise in Parkinson's disease

Abstract Introduction Studies in animal models of Parkinson's disease (PD) have suggested that the rate of exercise performance is important in treatment efficacy and neuroprotection. In humans with PD, lower-extremity forced-exercise (FE) produced global improvements in motor symptoms based on clinical ratings and biomechanical measures of upper extremity function. Methods fMRI was used to compare the underlying changes in brain activity in PD patients following the administration of anti-parkinsonian medication and following a session of FE. Results Nine individuals with PD completed fMRI scans under each condition: off anti-PD medication, on anti-PD medication, and off medication + FE. Unified Parkinson's Disease Rating Motor Scale scores improved by 50% in the FE condition compared to the off-medication condition. The pattern of fMRI activation after FE was similar to that seen with anti-PD medication. Direct comparison of the fMRI activation patterns showed high correlation between FE and anti-PD medication. Conclusion These findings suggest that medication and FE likely utilize the same pathways to produce symptomatic relief in individuals with PD.