None listed
Conditions
Brief summary
Regular exercise helps people with chronic obstructive pulmonary disease (COPD) to remain independent, stay out of hospital and live longer. However, current COPD clinical guidelines don’t provide clear, evidence-based recommendations around what intensity people with COPD should exercise at. Recommendations provided are based on healthy adults and don’t consider the limitations to breathing and high levels of breathlessness experienced by people with COPD. This may mean people with COPD exercise at intensities too high, causing intolerable breathlessness and negative exercise experiences, or too low, not eliciting health benefits. This study will evaluate the benefits of using respiratory-specific parameters to guide exercise prescription in COPD. We will compare the benefits of three, 6-week exercise training groups: (1) usual care, defined as 25 minutes of continuous cycle exercise at a breathlessness intensity of 3 (moderate) to 5 (severe) on Borg's 0-10 category ratio scale; (2) 25 minutes of continuous cycle exercise based on respiratory-specific parameters; (3) high intensity interval exercise training (HIIT, 4 lots of 4 minute exercise periods, interspersed with 3 minute rest periods) based on respiratory-specific parameters. Specifically, this study aims to answer two research questions: 1. Do people with COPD achieve greater adherence and health benefits from 6 weeks of continuous exercise prescribed based on respiratory specific parameters compared with current exercise training practices (usual care)? 2. Is it safe and feasible for people with COPD to perform HIIT prescribed based on respiratory specific parameters, to further maximise health benefits from an exercise training program?
Interventions
Participants will be randomised to one of three groups: 1) 25-minutes continuous exercise at a breathlessness intensity rating of between 3 to 5 on the 0-10 modified Borg scale (control); 2) 25-minutes continuous exercise at 90% of the critical inspiratory constraint threshold on tidal volume (CIC), where CIC is defined as the power output where a plateau in tidal volume (<0.15 L change) occurs despite increasing ventilation and the tidal volume is at least 73% of inspiratory capacity (interven
Participants will be randomised to one of three groups: 1) 25-minutes continuous exercise at a breathlessness intensity rating of between 3 to 5 on the 0-10 modified Borg scale (control); 2) 25-minutes continuous exercise at 90% of the critical inspiratory constraint threshold on tidal volume (CIC), where CIC is defined as the power output where a plateau in tidal volume (<0.15 L change) occurs despite increasing ventilation and the tidal volume is at least 73% of inspiratory capacity (intervention group 1); or 3) high intensity interval training (HIIT) at 110% CIC, with four 4-minute bouts of exercise interspersed with 3-minutes of rest at low intensity (intervention group 2). Each group will start and finish the exercise session with 5 minutes of low intensity cycling performed at 20% of peak power output. For all groups, exercise training will be performed on an electronically braked cycle ergometer, supervised by a trained exercise specialist (exercise scientist or accredited exercise physiologist), and consist of 3 sessions per week, for 6 weeks. The duration of each session (assessments and exercise training) will typically last around 1 hour. Throughout each exercise training session, participants in all groups will: * Rate their breathlessness intensity and unpleasantness using Borg's 0-10 Category Ratio scale (Borg's CR10) * Rate their level of leg discomfort using Borg's CR10 * Rate their affect using the Feeling Scale * Have their heart rate, peripheral oxygen saturation (pulse oximeter), and blood pressure assessed These measures will be taken before and after each session, and in the last 30-sec of the warmup and cool down, and every 5-minute interval during the training session for the control group and intervention 1 group, or at the end of every 4-min exercise bout for intervention 2 group (HIIT). Participants attendance to each exercise session will be recorded with an attendance checklist, and any deviations to the exercise training protocol will be recorded in an exercise training log. This includes rest periods (frequency and duration) and/or changes to prescribed intensity. Adverse events will be recorded in the adverse events log.
Sponsors
Dr Hayley Lewthwaite
Study design
Allocation
Randomised controlled trial
Intervention model
Parallel
Primary purpose
Treatment
Masking
Blinded (masking used) (Outcomes Assessor)
Eligibility
Sex/Gender
All
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
• Are aged 18 years or older • Self-report being previously diagnosed with COPD by a medical doctor • Meet spirometric criteria for COPD according to Global initiative for Obstructive Lung Disease criteria (forced expiratory volume in 1-sec to forced vital capacity ratio of <0.70 and/or less than the lower limit of normal) • Are willing and able to participate in a 6-week exercise training intervention involving cycle exercise
Exclusion criteria
• Have contraindications to lung function testing in accordance with international clinical guidelines13 (American Thoracic Society/European Respiratory Society; heart attack; lung collapse; blood clot in the lung; aneurysm; eye, chest or stomach surgery; or any history of coughing up significant amounts of blood in the previous 3 months) • Have significant extra-pulmonary disease that could impair exercise tolerance • Have an important contraindication(s) to cardiopulmonary exercise testing (e.g., significant cardiovascular, musculoskeletal, neurological disease) • Changed their respiratory medication dosage and/or frequency of administration in the preceding two weeks • Had a disease exacerbation/hospitalisation in preceding six weeks
Outcome results
None listed