The Acute Cardiorespiratory Response to Blood-flow Restricted Versus Traditional Exercise Training Regimens (CaRe BFR)

This study is comparing blood-flow restriction (BFR) exercise — where a cuff is used to partially limit blood flow during low-intensity exercise — with traditional exercise, to understand how each affects the heart and lungs. The study includes both healthy people and those with COPD (chronic lung disease). **You may be eligible if...** - You are 18 years of age or older - You are either clinically healthy OR you have been diagnosed with COPD according to standard guidelines - You can speak and understand German (required for informed consent) **You may NOT be eligible if...** - You have a physical or intellectual impairment that prevents safe participation - You experience pain during exercise - You are pregnant - You have had a blood clot in your leg (deep vein thrombosis) - Your resting blood pressure is very low (below 100 mmHg systolic) - For COPD group: you have had a flare-up in the last 6 weeks Talk to your doctor to see if this trial is right for you.