Inclusion and exclusion for the healthy participants are defined by the following criteria.  Inclusion criteria:  Age ≥ 18 years Clinically healthy  Exclusion criteria:  Physical or intellectual impairment precluding informed consent or protocol adherence Non-German speaking (precluding informed consent) Pain during exercise of any origin Pregnancy History of thromboembolic event in the lower extremity Resting systolic blood pressure <100 mmHg  Inclusion and exclusion for the COPD participants are defined by the following criteria.  Inclusion criteria:  Age ≥ 18 years Diagnosed COPD according to GOLD-guidelines12  Exclusion criteria:  Physical or intellectual impairment precluding informed consent or protocol adherence Non-German speaking (precluding informed consent) Acute or recent (within the last 6 weeks) exacerbation of COPD Pain during exercise of any origin Pregnancy History of thromboembolic event in the lower extremity Resting systolic blood pressure <100 mmHg