title: Exercise-induced neuroplasticity in human Parkinson's disease: What is the evidence telling us?
abstract: BACKGROUND
  While animal models of exercise and PD have pushed the field forward, few studies have addressed exercise-induced neuroplasticity in human PD.
  
  
  METHODS
  As a first step toward promoting greater international collaboration on exercise-induced neuroplasticity in human PD, we present data on 8 human PD studies (published between 2008 and 2015) with 144 adults with PD of varying disease severity (Hoehn and Yahr stage 1 to stage 3), using various experimental (e.g., randomized controlled trial) and quasi-experimental designs on the effects of cognitive and physical activity on brain structure or function in PD. We focus on plasticity mechanisms of intervention-induced increases in maximal corticomotor excitability, exercise-induced changes in voxel-based gray matter volume changes and increases in exercise-induced serum levels of brain derived neurotrophic factor (BDNF). Finally, we provide a future perspective for promoting international, collaborative research on exercise-induced neuroplasticity in human PD.
  
  
  CONCLUSIONS
  An emerging body of evidence suggests exercise triggers several plasticity related events in the human PD brain including corticomotor excitation, increases and decreases in gray matter volume and changes in BDNF levels.
authors.affiliation: Carolinas Rehabilitation, Department of Physical Medicine and Rehabilitation, and Carolinas Neurosciences Institute, Carolinas Medical Center and HealthCare System, Charlotte, NC, USA. Electronic address: mark.hirsch@carolinashealthcare.org.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Hirsch
authors.affiliation: Carolinas Rehabilitation, Department of Physical Medicine and Rehabilitation, and Carolinas Neurosciences Institute, Carolinas Medical Center and HealthCare System, Charlotte, NC, USA.
authors.forename: Sanjay S
authors.initials: SS
authors.lastname: Iyer
authors.affiliation: Carolinas Rehabilitation, Department of Physical Medicine and Rehabilitation, and Carolinas Neurosciences Institute, Carolinas Medical Center and HealthCare System, Charlotte, NC, USA.
authors.forename: Mohammed
authors.initials: M
authors.lastname: Sanjak
mesh_terms: D002540:Cerebral Cortex / Q000378:metabolism; D015444:Exercise / Q000502:physiology*; D005081:Exercise Therapy / Q000379:methods*; D006801:Humans; D009414:Nerve Growth Factors / Q000378:metabolism; D009473:Neuronal Plasticity / Q000502:physiology*; D010300:Parkinson Disease / Q000378:metabolism* / Q000628:therapy*
chemical_list: D009414:Nerve Growth Factors
keywords: Exercise; Human; Neuroplasticity; Neurotrophic factor; Parkinson's disease