What additional TWO muscles plya a role in MAXIMAL inspiration?

"The muscles of respiration are also called the 'breathing pump muscles', they form a complex arrangement in the form of semirigid bellows around the lungs. All muscles that are attached to the human rib cage have the inherent potential to cause a breathing action. Muscles that helpful in expanding the thoracic cavity are called the inspiratory muscles because they help in inhalation, while those that compress the thoracic cavity".

Explanation:

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