The study is about understanding how the muscles that help us breathe work in people with Chronic Obstructive Pulmonary Disease, or **COPD**. COPD is a lung disease that makes it hard to breathe. Researchers will use a tool called **MyotonPro** to measure how these muscles perform in people with COPD and compare them to healthy people.

Key points to consider:

• The study is for people diagnosed with group C or D COPD, as well as healthy individuals over 18 who don't smoke or have chronic diseases.
• Participants with recent COPD flare-ups or other lung diseases can't join.
• The study requires participants to have consistent medication use for 4 weeks before joining and must not have fatty tissue at measurement points.

Participation is voluntary, and it's crucial for participants to meet specific health criteria. If you have COPD, have been stable in your medication, and don't have other significant health issues, you might be eligible. Healthy people must be non-smokers and free from chronic diseases. This research will help doctors better understand COPD and improve treatments.