GLOSSARY

The accessory muscles of respiration play little part in quiet breathing but are recruited to increase ventilation during deep breathing, intense exercise, or respiratory disease.

Accessory Inspiratory Muscles

• Sternocleidomastoid: raises the sternum.
• Scalenes: raise the first and second ribs; some research shows them active even in quiet breathing.
• Pectoralis minor and major: when the shoulders are fixed.
• Serratus anterior, trapezius, and levatores costarum.

Accessory Expiratory Muscles

• Abdominal muscles: rectus abdominis, obliques, and transversus abdominis, raising intra-abdominal pressure and pushing the diaphragm upward.
• Latissimus dorsi: in coughing and forced expiration.

Clinical Signs

• Use of accessory muscles at rest (prominent neck muscles, raised shoulders) is a sign of respiratory distress in an asthma attack, COPD, or pneumonia.
• Tripod position: leaning forward with hands on the knees, fixing the shoulders for better use of the pectoral muscles.

Relevance to Sport

• After intense exercise: many athletes instinctively adopt the hands-on-knees position; research shows this may improve heart rate recovery and ventilation compared with hands on the head.
• Dysfunctional breathing pattern: upper-chest breathing with overactive scalenes and trapezius at rest may be associated with neck pain and shoulder tension; diaphragmatic breathing training helps.