The goal of this clinical trial is to investigate the effects of elastic chest compression on functional exercise capacity and respiratory performance of patients with COPD. The main questions it aims to answer are:

Is there difference in functional exercise capacity and respiratory performance without or with the use of elastic upper chest compression? Is there difference in functional exercise capacity and respiratory performance between the use of elastic upper chest compression and elastic lower chest compression?

Participants will:

Be evaluated under three conditions on three different days: without elastic compression, with upper chest compression, and with lower chest compression, with the order of compression application randomly assigned.

The functional capacity and respiratory muscle performance of all patients will be evaluated.

The days for evaluation will be at least three days apart from each other.

Participants will be evaluated under three conditions: without elastic compression, with upper chest compression, and with lower chest compression, with the order of compression application randomly assigned. A Red Theraband will be used to apply compression to the upper and lower regions of the chest. For a standardized approach to apply compression, the top edge will be aligned with the 3rd intercostal space for the upper chest compression, while the central horizontal part will line up with the xiphoid process of the sternum for the lower chest compression. After exhaling to the EELV, the circumferences of the upper and lower chest regions will be measured, using the 3rd intercostal space as the measurement mark for the upper chest and the xiphoid process of the sternum as the measurement marks for the lower chest. The Thera-Band will be adjusted to 90% of the measured circumferences, ensuring it is securely fastened and standardized resistance is applied consistently to the thoracic regions of interest throughout the study. After chest compression is applied, participants will undergo measurements for functional exercise capacity and respiratory muscle performance.

Inclusion Criteria:

• at least 20 years old
• has a clinical diagnosis of COPD without infection or acute exacerbation in the previous four weeks
• is capable of cooperating with the required tests and measurements of the study

Exclusion Criteria:

• has any clinical diagnosis that could affect test outcomes (e.g., neuromyopathy)
• has experienced unstable angina or an acute myocardial infarction within the last month
• has adjusted COPD related medication within the last month
• a Mini-Mental State Examination (MMSE) score below 24