Exercise response in Parkinson’s Disease : insights from a cross-sectional comparison with sedentary controls and a per protocol analysis of a randomised controlled trial

Objectives: To investigate the acute and adaptation cardiovascular and metabolic training responses in people with Parkinson’s (pwP). Design: 1) A cross sectional study of exercise response of pwP compared to sedentary controls,2) an interventional study of exercise training in pwP. Setting: Community leisure facilities. Participants: pwP (n=83) & sedentary controls (n=55) Interventions: Study (1) included participants from a two arm parallel single blind phase II Randomised Controlled Trial (RCT), that undertook a baseline maximal incremental exercise test and study (2) included those randomised to the exercise group in the RCT, who completed a six-month weekly exercise programme (n=37). The intervention (study (2) was a prescribed exercise program consisting of sessions lasting 60 minutes, twice a week over a six-month period. The control group followed the same protocol which derived the same cardio respiratory parameters, except the they were instructed to aim for a cadence of ~60rpm and the unloaded phase lasted 3minutes with an initial step of 25watts. Primary and secondary outcome measures: Stepwise incremental exercise test to volitional exhaustion was the primary outcome measure. Results: Study (1) showed higher maximum values for heart rate, VO2l.min-1, VCO2l.min-1 and Ventilation l.min-1 for the control group; Respiratory Exchange Ratio (RER), perceived exertion and O2 Pulse (VO2l.min-1/ HR) did not differ between groups. In study (2), for pwP who adhered to training (n=37), RER increased significantly and although there was no significant change in aerobic capacity or heart rate response, reduced blood pressure was found. Conclusions: An abnormal cardiovascular response to exercise was observed in pwP compared to controls. After the exercise programme, metabolic deficiencies remained for pwP. These observations add to the pathogenic understanding of PD, acknowledge an underling metabolic contribution and support that certain cardiovascular symptoms may improve as a result of this type of exercise Trial registration: ClinicalTrials.Gov (NCT01439022)