In Pilates, which group of muscles assists with rib cage movement during breathing?

The intercostal muscles play a critical role in rib cage movement during breathing. These muscles are located between the ribs and are primarily responsible for expanding and contracting the rib cage as we inhale and exhale. During inhalation, the intercostal muscles contract to lift the ribs upward and outward, which increases the volume of the thoracic cavity and allows air to enter the lungs. Conversely, during exhalation, these muscles help to lower the ribs back to their resting position, assisting in the expulsion of air from the lungs.

While the diaphragm is indeed a primary muscle involved in breathing, it operates differently than the intercostal muscles. The diaphragm primarily separates the thoracic cavity from the abdominal cavity and moves downward during inhalation, creating a vacuum that draws air into the lungs. The serratus anterior and pectoralis major have roles in different movements and stabilization of the shoulder girdle, but they do not significantly assist in rib cage movement during breathing. Thus, the intercostal muscles are the correct answer in the context of rib cage mechanics during respiration.