Chronic Obstructive Pulmonary Disease (COPD) is a â€œheterogeneous lung condition characterized by chronic respiratory symptoms (dyspnea, cough, expectoration, exacerbations) due to abnormalities of the airways (bronchitis, bronchiolitis) and/or alveoli (emphysema) that cause persistent, often progressive, airflow obstruction. Muscle Energy Techniques (MET) are a form of soft-tissue, or joint, manipulations or mobilizations, deriving from those employed in the treatment of musculoskeletal dysfunction, where the patient participates actively in the treatment (through isometric and/or isotonic contractions). The study aims to investigate the effect of muscle energy technique for muscles aiding in breathing on maximum voluntary ventilation (MVV) in patients diagnosed with COPD. The study includes group control group and interventional group. Control group recieved conventional Physiotherapy and the interventional group was intervened with Muscle energy technique for respiratory muscles for 1 week. Participants diagnosed with COPD and vitally stable will be included in the study. Participants will be assessed pre and post-intervention via an assessment form; also written consent will be signed. Participants would be assessed on day 1 and reassessed on day 6. Post-intervention statistical analysis would be done and results would be extracted to evaluate the efficacy of intervention.