Effects of endurance exercise training on the motor and non-motor features of Parkinson's disease: a review.

Background: Despite the benefits of medications and surgical interventions for Parkinson's disease (PD), these treatments are not without complications and neuroprotective strategies are still lacking. Therefore, there is a need for effective alternative approaches to treat motor and non-motor symptoms in PD. During the last decade, several studies have investigated endurance exercise training as a potential treatment for individuals with PD.
Objective: This paper reviews the therapeutically beneficial effects of endurance exercise training on motor and non-motor symptoms in PD.
Methods: First, we performed a systematic review of the literature on the effects of endurance exercise training on motor and non-motor signs of parkinsonism, functional outcomes including gait, balance and mobility, depression and fatigue, quality of life and perceived patient improvement, cardiorespiratory function, neurophysiological measures, and motor control measures in PD. Second we performed a meta-analysis on the motor section of the UPDRS. Then, we focused on several important factors to consider when prescribing endurance exercise training in PD such as intensity, duration, frequency, specificity and type of exercise. In addition, we identified current knowledge gaps regarding endurance exercise training in PD and made suggestions for future research.
Results: A total of eight randomized controlled trials met the inclusion criteria and were reviewed. This systematic review synthesizes evidence that endurance exercise training at a sufficiently high level enhances cardiorespiratory capacity and endurance by improving VO2 max and gait in moderately to mildly affected individuals with PD. However, there is not yet a proven effect of endurance exercise training on specific features of PD such as motor signs of parkinsonism.
Conclusion: Endurance exercise training improves physical conditioning in PD patients; however, to date, there is insufficient evidence to include endurance exercise training as a specific treatment for PD. There is a need for well-designed large-scale randomized controlled trials to confirm benefits and safety of endurance exercise training in PD and to explore potential benefits on the motor and non-motor signs of PD.