High-intensity interval training in people with Parkinson's disease: a randomized, controlled feasibility trial

Objectives: To investigate whether people with Parkinson's disease can exercise at a high-intensity across a 12-week intervention and to assess the impact of the intervention on cardiorespiratory fitness. Design: This is a randomized, controlled, feasibility study with waiting list control. Assessors were blinded to group allocation. Setting: The intervention took place at an exercise centre and assessments at a district general hospital. Subjects: This study included 20 people with idiopathic Parkinson's disease. Intervention: A total of 36 exercise sessions over 12 weeks, with each session lasting similar to 45 minutes, were conducted. Main measures: The main measures were maximal heart rates achieved during exercise, recruitment rate, attendance, drop-out, change in peak oxygen consumption, cardiac output, cognitive function and quality of life. The study was considered technically feasible if participants achieved > 85% of maximal heart rate during exercise. Results: There were 12 male and 8 female participants; they had a mean age of 68.5 years (standard deviation 6.825). Two participants were of Hoehn and Yahr stage I, 11 stage II and 7 stage III. In all, 17 participants completed the intervention. The median (interquartile range) proportion of repetitions delivered across the intervention which met our high-intensity criterion was 80% (67% to 84%). Mean peak heart rate was 88.8% of maximal. Peak oxygen consumption increased by 2.8 mL kg(-1) min(-1) in the intervention group and 1.5 mL kg(-1) min(-1) in the control group after 12 weeks of exercise. We estimate that a fully powered randomized controlled trial would require 30 participants per group. Conclusion: High-intensity interval exercise is feasible in people with Parkinson's disease. Improvements in cardiorespiratory function are promising.