A short description, 5000 characters Intro: In phenotypic animal models of Parkinson's Disease (PD), chronic physical exercise has produced nigrostriatal neuroprotection and symptom improvement, provided training was of high-intensity and prolonged duration (>3 months in rodent models). Conventional physical therapy in Parkinson's disease (PD) has traditionally avoided fatigue and high intensity workouts. Yet, in PD controlled studies have shown that: (i) an acute aerobic stress produces endogenous dopamine immediately after the exercise and (ii) short term (a few weeks) high intensity aerobic training enhances D2 striatal receptor density and cortical excitability and clinically improves walking, upper limb and executive functions; (iii) long-term (six months) high intensity aerobic treadmill training is associated with less deterioration of subjective UPDRS III score compared to a waiting list. Long-term high intensity aerobic training has not been compared to low or medium intensity training in PD patients for its objective motor, cognitive and putative neuroprotective effects.~Hypothesis/Objective~Hypothesis High-intensity aerobic exercises practiced over 9 months will produce greater symptomatic motor and cognitive benefits and neuroprotective effects in PD patients, than low or medium intensity training.~Primary Objective To compare the motor effects of a 9-month conventional physical therapy program (light aerobic exercises), an aerobic program of medium intensity on stationary bicycle (50% maximal oxygen uptake, VO2 max), and an aerobic program of high intensity (70% VO2 max) in Parkinson's disease.~Secondary Objectives~To evaluate aerobic capacities before and after the program.~To evaluate cognitive functions, depression, quality of life before and after each program as well as 3 months following program termination and motor function 3 months following program termination.~To explore potential neuroprotective effects of a 9-month aerobic program through specialized brain imaging (123I-Ioflupane SPECT) and a potential aerobic intensity-effect of such neuroprotection.~Primary outcome measure Change in MDS-UPDRS III Score (Movement Disorders Society - Unified Parkinson's Disease Rating Scale) in the  OFF  state between Day 1 and Month 9.~Secondary outcome measures OFF-state at Day 1, Month 9, Month 12~Two-minute walking test from D1 to M9~Modified 20-meter up-and-go test (AT20)~2-minute walk test (from M1 to M12)~Global Mobility Task (GMT) scale (standing up off the floor)~Upper limb performance in activities of daily living (Mount Sinai Parkinsonism Impairment Rating Scale, MSPIR)~Static posturography~Maximal aerobic capacity (VO2 max)~Montreal Cognitive Assessment test (MoCA)~Digit span task (forward and backward)~Trail Making Test~ON-state at D1, M9, M12~MDS-UPDRS III Score;~Mean number of steps performed over the past three weeks (pedometry);~Monthly incidence of falls in the past 3 months (questionnaire)~Daily consumption of dopaminergic medications~Quality of life (EQ-5D)~Depression (GDS15)~Dopaminergic striatal function by SPECT [123I] beta-CIT striatal uptake at D1, M12.~Method Design~Single-blind randomized study, 3 parallel groups (n= 7 or 8 per group and per center, over 3 centers):~Group 1  High Intensity Aerobic exercise , HIA (70% VO2 max);~Group 2  Medium Intensity Aerobic exercise , MIA (50% VO2 max);~Group 3  Conventional Physical Therapy , CPT HIA and MIA groups are experimental groups and CPT group is the control group. Each group will attend 3 weekly 45-minute sessions at the hospital for 9 months.~Number of subjects needed: 69 Inclusion criteria Patients with diagnosis of PD according to the UKPDSBB criteria to distinguish idiopathic PD from atypical parkinsonism such as multi-system atrophy, progressive supra-nuclear paralysis or vascular parkinsonism; Previous MRI available, to further help distinguish idiopathic PD from atypical parkinsonism; Hoehn & Yahr Stage 1-3 in OFF state; Age > 18; Signed informed consent to participate in study.~Non-inclusion criteria Patients lacking motivation or ability to participate in training sessions for 9 months, in the investigator's opinion; contra-indications to high-intensity aerobic training in the cardiologist's opinion; contra-indications to perchlorate de potassium or to the use of 123I-FP-CIT; concurrent severe co-morbidities; cognitive deficit limiting participation to the program; Montreal Cognitive Assessment test (MoCA)<23; uninsured patient; participation in another ongoing interventional clinical trial (drug therapy, surgical treatment, another rehabilitation treatment, medical device); Pregnancy or current lactation, or no efficacious contraception during the 9 months of intervention.~Recruitment period: 1 year; Study duration: 26 months (24 patients recruited in 2 centers and 21 patients in the other 2 centers) Participation duration for each patient: 14 months Number of participating centers: 3
In phenotypic animal models of Parkinson's Disease (PD), chronic physical exercise has produced nigrostriatal neuroprotection and symptom improvement, provided training was of high-intensity and prolonged duration (>3 months in rodent models). Conventional physical therapy in Parkinson's disease (PD) has traditionally avoided fatigue and high intensity workouts. Yet, in PD controlled studies have shown that: (i) an acute aerobic stress produces endogenous dopamine immediately after the exercise and (ii) short term (a few weeks) high intensity aerobic training enhances D2 striatal receptor density and cortical excitability and clinically improves walking, upper limb and executive functions; (iii) long-term (six months) high intensity aerobic treadmill training is associated with less deterioration of subjective UPDRS III score compared to a waiting list. Long-term high intensity aerobic training has not been compared to low or medium intensity training in PD patients for its objective motor, cognitive and putative neuroprotective effects.