Criteria for inclusion | Written informed consent Age: 18–30 or 60–80 years, respectively Adequate age-based response to physical stress Normal performance of upper limbs |
Criteria for exclusion | Missing consent Long-term medication Acute medication (within the past 14 days) Peripheral arterial disease Diabetes mellitus Hypertension, NYHA > II Pre-existing nerve damage of the upper limb Status after thrombo-embolic events Smoking (within the past 5 years, > 10 pack years) Pregnancy Chronic pain disorders and psychiatric or neurologic disorders leading to missing legal competence |