Effects of Blood Flow Restriction Aerobic Exercise on Inflammation, Hypoxia, Exercise Capacity, and Lung Function in COPD

Inclusion Criteria: * Individuals aged between 40 and 80 years * Clinically stable patients diagnosed with Chronic Obstructive Pulmonary Disease (COPD) according to GOLD 2024 criteria with post-bronchodilator FEV₁/FVC \< 0.70 * Stable clinical condition (no acute exacerbation within the past 4 weeks) * Individuals clinically evaluated and approved as suitable for pulmonary rehabilitation (PR) participation by a cardiology specialist * Functional capacity sufficient to participate in PR (e.g., 6-Minute Walk Test ≥150 m) * No contraindications to blood flow restriction (BFR) training (e.g., no peripheral vascular disease, no active thrombosis) * Ability to understand and follow instructions (adequate auditory and cognitive function) Exclusion Criteria: * Acute exacerbation of COPD, hospitalization, or systemic corticosteroid treatment within the past 4 weeks * Severe cardiovascular disease (uncontrolled hypertension \>180/110 mmHg, myocardial infarction within the past 6 months, unstable angina, congestive heart failure NYHA Class III-IV) * Neurological or orthopedic conditions significantly limiting lower-extremity function (e.g., hemiplegia, amputation, severe osteoarthritis, knee prosthesis) * Severe renal impairment (GFR \<30 mL/min/1.73 m²) or severe hepatic failure * History of lower-extremity surgery within the past 3 months * Active malignancy or systemic infection * Anemia or chronic inflammatory/autoimmune diseases (e.g., rheumatoid arthritis, systemic lupus erythematosus, inflammatory bowel disease) * History of venous thromboembolism * Peripheral arterial disease * Physician-diagnosed sarcopenia * Psychiatric disorders (major depression, dementia, psychotic disorders) limiting adherence to the study protocol