Supramaximal High-Intensity Interval Training in People With and Without Chronic Obstructive Pulmonary Disease

The inclusion criteria are: 1. 60 years of age or older 2. Independent in activities of daily living 3. For people with COPD: Symptomatic (COPD assessment test \[CAT\] ≥10 or modified Medical Research Council dyspnea scale \[mMRC\] ≥2) or not being regularly physically active at a moderate or high intensity over the last year defined as not meeting WHO requirements for physical activity. 4. For people with COPD: Post-bronchodilator spirometry confirmed COPD diagnosis (forced expiratory volume in one second (FEV1) to forced vital capacity (FVC) ratio \< 0.70). 5. For healthy controls: Normal lung function The exclusion criteria are: 1. Movement related conditions, cardiovascular, neuromuscular, metabolic, skeletal and/or rheumatic conditions and diseases that are unstable and/or prohibits exercise or tests, based on screening by a physician. For example, but not limited to: I. Musculoskeletal pain prohibiting participation in tests and exercise II. Recent myocardial infarction, coronary artery bypass grafting, angioplasty, or other cardiac events III. Uncontrolled arterial hypertension IV. Pathological ECG-findings during CPET 2. Other lung conditions, including, but not limited to asthma, interstitial lung disease, lung cancer, pulmonary hypertension, pulmonary vascular disease, pulmonary fibrosis 3. Medical conditions and treatments with known effects on brain function and cognition, for example: I. Previous trauma to the head with lasting cognitive or symptom-related issues II. Physical or mental disabilities III. Neurological condition (dementia, multiple sclerosis, stroke) IV. Psychiatric illness, not including depression or general anxiety disorder V. Severe cognitive impairment VI. Recent or current cancer diagnosis and treatment 4. For those accepting MRI or PET/CT: metal implants, pacemakers, claustrophobia and other MRI incompatible factors. 5. Inability to read or speak Swedish (Umeå participants), Dutch, French (Hasselt participants) or English (Umeå and Hasselt participants). 6. For people with COPD: I. Co-morbid conditions that limit exercise performance to a greater extent than the COPD diagnosis. II. Currently participating in a pulmonary rehabilitation program or have been involved in pulmonary rehabilitation in the last 12 months. III. Experienced a COPD exacerbation that led to a change in medication dosage or frequency in the preceding six weeks.