kyphotic subjects have respiratory disturbances due to weakening of the diaphragm, responsible for inhalation, which lead to abnormalities in respiratory mechanics and abnormal gas exchange, leading to respiratory complications. Myofascial release of the diaphragm is an intervention intended to indirectly stretch the diaphragm muscle fibers to reduce muscle tension, normalize fiber length, and promote the efficiency of muscle contraction. Although diaphragm myofascial release has been used in clinical practice, to the best of the authors' knowledge, the current study is the first research investigating the effect of diaphragmatic myofascial release on lung function, chest mobility and kyphotic curve in hyperkyphotic subjects.

Inclusion Criteria:

• The participant's age ranged from 20 to 40 years.
• kyphosis angle 40-50◦
• reporting pain on palpation of the diaphragm

Exclusion Criteria:

• A history of respiratory diseases, heart disease, vascular disease, central nervous system disorder, psychiatric disorders, hypertension.
• History of any trauma or fracture to the thoracic spine.
• inflammatory diseases such as rheumatoid arthritis, musculoskeletal problem and neurological deficit
• Restrictive respiratory disease, smokers.