The purpose of the study will investigate the safety and effectiveness with eight-week cycling-cognitive dual-task training for early Parkinson's disease.

Background: Parkinson's disease is a neurodegenerative disorder of the basal ganglia in which the production of dopamine is reduced, leading to the motor and non-motor impairment and the loss of automaticity. Recently, the results across studies have indicated that motor-cognitive dual-task deficits in individuals with neurologic disorders appear to be amenable to training. Improvement of dual-task ability in individuals with neurologic disorders holds potential for improving gait, balance, and cognition. The most recent European guideline provides a more graded view, stating that in Hoehn and Yahr stages 2 and 3 dual-task training may be safe and effective. An overview of current ongoing randomized controlled trials focusing on dual-task rehabilitation, gait training or treadmill training was the major motor-task. However, cycling augmented by cognitive training has not been evaluated. In addition, antioxidant capacity is unclear for Parkinson's disease patients with long-term, regular cycling training.

Study purpose: The purpose of the study will investigate the safety and effectiveness with eight-week cycling-cognitive dual-task training for early Parkinson's disease. The antioxidant capacity will be assessed as well.

Methods: Parkinson's disease patients will be assigned to cycling training, cycling-cognitive dual task training, and following 8 weeks. All of the subjects will complete 3 assessments at pre-training, post-4 weeks, and post-8 weeks. The outcome measures are clinical severity and disability, performance of gait-cognitive and cycling-cognitive, cognitive-task performance, peripheral-blood oxidative stress, adverse events, etc.

Significance: In this study, evidence-based practice as the foundation, and perspective to design a safe and effective cycling-cognitive dual-task training for early Parkinson's disease. It can be verified in the clinical application of these experiments feasibility (practice-based evidence).

Inclusion Criteria:

• patients with Idiopathic Parkinson's disease (IPD)
• an age between 45 to 70 years
• asymmetrical onset of at least 2 of 3 cardinal sign
• Modified Hoehn and Yahr staging from 1 to 2.5 during off state
• Montreal cognitive assessment score of 26 or greater

Exclusion Criteria: The patients were ineligible if they had

• a neurological history other than Parkinson's disease
• ever undergone neurosurgery for Parkinson's disease
• had moderate to severe dyskinesia
• been unstable with medical or psychiatric co-morbidities, orthopedic conditions restricting exercise
• done more than 20 min of aerobic exercise over 3 sessions per week on their own

after publishing, we will share IPD