Inspiration Mechanics: Chest Wall Expansion Drives Lung Inflation
Physics of Inhalation
- Diaphragm Contracts: Flattens, descends → ↑ vertical thoracic volume.
- External Intercostals Contract: Elevate ribs → ↑ anteroposterior & lateral dimensions (bucket-handle + pump-handle motion).
- Thoracic Volume ↑ → Intrapulmonary Pressure ↓ (subatmospheric).
- Pressure Gradient: Atmospheric pressure > alveolar pressure → air flows in.
- Lung Expansion: Elastic recoil of lung + chest wall outward pull → alveoli expand.
- Gas Exchange: O₂ diffuses into pulmonary capillaries; CO₂ diffuses out.
Expiration (Passive at Rest)
Muscles relax → elastic recoil of lungs/chest wall → volume ↓ → pressure ↑ → air flows out.
Forced Breathing
Accessory muscles (sternocleidomastoid, scalenes, pectoralis minor) augment inspiration; internal intercostals, abdominals drive forced expiration.
Breathwork - Related Articles
- Wetting Yourself and Then Showering: Health Risks and Reality Check
- MERS-CoV: Lung Infection Mechanism, Transmission, and Clinical Features
- Oxygen Therapy During Resuscitation: Why 100% O2 Is Standard & Exceptions
- Secondhand Smoke & Vocal Cord Damage: Evidence & Protection
- Stethoscope: Medical Instrument for Auscultation of Heart, Lungs, and Bowel Sounds
- Humorous Comebacks for Bad Breath (Use With Caution & Kindness)
- Voice Recovery After Smoking Cessation: Evidence-Based Strategies