biomechanics of breathing

Breathing is driven by the diaphragm and intercostal muscles that control lung volume. When you inhale, the diaphragm contracts and moves downward, while the chest muscles expand the rib cage, increasing lung space. This creates a negative pressure inside the lungs, causing air to flow in. During exhalation, these muscles relax, the diaphragm moves upward, and the chest returns to its resting shape, pushing air out. This process is regulated by your brain to match your body's oxygen needs and remove carbon dioxide, maintaining efficient gas exchange essential for survival.