respiratory muscles
Medical/anatomical term for the muscles involved in breathing, such as the diaphragm and intercostal muscles.
呼吸筋が弱ると、呼吸が苦しくなることがあります。
When the respiratory muscles weaken, breathing can become difficult.
Compound of 呼吸 (kokyū, 'breathing') and 筋 (kin, 'muscle').