Which sheet of skeletal muscle contracts to draw air into the lungs and is used by singers to produce powerful notes?

• A. Intercostal muscles
• B. Diaphragm
• C. Pectoralis major
• D. Trachea

Answer: (B)

Breath control for singing relies on the diaphragm, the main sheet of skeletal muscle that contracts to draw air into the lungs. Located below the lungs, the diaphragm flattens when it tightens, increasing the vertical space of the chest cavity and creating negative pressure that pulls air in. This diaphragmatic breathing gives singers a steady, powerful breath supply, essential for sustaining strong notes and controlling phrasing. Intercostal muscles assist breathing by expanding the rib cage, but they aren’t the primary muscle that draws air in. The pectoralis major is a chest muscle used for arm movements, not respiration, and the trachea is an airway, not a muscle.