Strength Training and Medication Effects in Parkinson Disease Effects on Hypokinesia in Parkinson Disease
Strength Training and Medication Effects in Parkinson Disease Effects on Hypokinesia in Parkinson Disease
Parkinson disease is a degenerative neurologic condition characterized by slowness of
 movement, tremor, and loss of balance control. It results in significant degrees of
 disability for affected individuals. Exercise and medication management are two treatments
 frequently used to treat Parkinson disease, and although some individuals benefit from these
 treatments, by what effect exercise works is presently not known. We will examine muscle
 structure and movement control responses to strengthening exercises and compare them to the
 therapeutic response observed as a result of medication intake. This process will allow us to
 better understand the mechanisms underlying the therapeutic effects of strengthening exercise
 for persons with Parkinson disease.
Idiopathic Parkinson disease (IPD) is the model movement disorder to explore the motor
 function of the basal ganglia. (Morris ME, 2005) Alterations in the output of the basal
 ganglia lead to reductions in muscle force output and movement amplitude while inactivity and
 impaired mobility contribute to the loss of muscle size and strength.

 Collectively these factors lead to reductions in the size and speed (hypokinesia) of
 functional movements such as gait. Hypokinesia during gait initiation and gait are
 biomechanical events that can precipitates movement deficits such as bradykinesia and falls.
 Previous studies have suggested that resistance training is beneficial in the management of
 persons with PD. Although anatomic, behavioral, and mobility related improvements have been
 demonstrated with resistance training intervention, it is unclear if the observed changes are
 derived solely from peripheral musculoskeletal changes or from central nervous system
 mediated alterations in force output and movement amplitude. The responsiveness of muscle
 force, movement amplitude, and hypokinesia to the CNS mediated effects of dopamine
 replacement provide a model system to which the effects of resistance training can be
 compared. In order to examine this question, we plan to conduct a controlled trial to
 rigorously examine the effects of high force resistance training on muscle structure, muscle
 force output, and hypokinesia in persons with moderate IPD and in the process, characterize
 the potentially differential effects of resistance training effects and dopamine replacement.
 This study assembles a team of investigators with experience in high force resistance
 training, measurement of the biomechanical and clinical balance function in persons with PD,
 and the statistical analysis expertise. Persons with IPD will be recruited, examined, and if
 they meet the inclusion criteria will be randomly assigned to one of two groups (experimental
 or standard care control). A battery of tests including muscle structure, muscle force
 production, and measures of hypokinesia and will be assessed on and off dopamine replacement
 medication both prior to and after a 12 week resistance training intervention. The first
 specific aim of the study is to determine if high force resistance training results in
 improvements in muscle structure, muscle force output, and hypokinesia in persons with
 moderate IPD. The second specific aim is to characterize and compare any differential effects
 of high force resistance training and dopamine replacement on muscle force output and
 hypokinesia in persons with moderate IPD. We hypothesize that dopamine replacement and
 resistance training will interact to improve muscle force output and reduce hypokinesia. In
 addition, we hypothesize that examination of kinematic patterns during gait initiation will
 reveal differential effects on lower extremity hypokinesia. The results of this study will
 help to better understand the differential contributions of resistance training and dopamine
 replacement on hypokinesia in persons with PD.
Inclusion Criteria:

 male or a female at least 40 years of age or older neurologist diagnosed idiopathic PD
 (using UK Brain Bank Criteria) ambulatory and medically cleared by their physician to
 participate in an exercise regimen clinical signs of hypokinesia (reduced movement
 amplitude during ADL tasks) or postural instability have a Folstein Mini-Mental State
 Examination score > 23 currently taking dopamine replacement medication

 Exclusion Criteria:

 previous surgical management of PD (pallidotomy, DBS) motor fluctuations and or dyskinesias
 uncontrolled by medications. central nervous system disorder (e.g., other than Parkinson's
 disease) myopathic disease (e.g., focal myopathy) that affects skeletal muscle
 structure/function rheumatological disease that has an effect on muscle and/or mobility
 unstable cardiovascular disease that limits exercise abilities impaired knee flexion, <90
 degrees, extreme claustrophobia (secondary to the inability to perform the MRI scans)
 regular (2-3x/week) aerobic or resistance exercise performed over the past 6 months