| A | B |
|---|
| Erector Spinae Group (unilaterally) | Laterally flex the vertebral column to same side |
| Erector Spinae Group, Semispinalis Capitis, Multifidi & Rotatores (bilaterally) | Extend the vertebral column |
| Diaphragm | Draw down the central tendon of diaphragm, increase volume of thoracic cavity during inhalation |
| Sternocleidomastoid (unilaterally) | Laterally flex head/neck to same side |
| Sternocleidomastoid (bilaterally) | Flex neck, assist in inhalation via elevation of ribcage |
| Serratus posterior superior | Elevate ribs during inhalation |
| Serratus posterior inferior | Depress ribs during exhalation |
| Internal intercostals | Assist in exhalation by drawing the ribs inferiorly |
| External intercostals | Assist with inhalation by drawing the ribs superiorly |
| Rectus Capitis Posterior Minor & Oblique Capitis Superior | Rock and tilt head/neck into extension |
| Rectus Capitis Posterior Major | Rock & tilt head/neck into extension, rotate head to same side |
| Oblique Capitis Inferior | Rotate head to same side |
| Rotatores & Multifidi (unilaterally) | Rotate the vertebral column to opposite side |
| External Oblique (unilaterally) | Laterally flex, and rotate vertebral column to the opposite side |
| External Oblique & Internal Oblique (bilaterally) | Flex the vertebral column, compress abdominal contents |
| Rectus Abdominus | Flex the vertebral column |
| Quadratus Lumborum (unilaterally) | Laterally tilt pelvis, laterally flex vert. column to same side, assist to extend vert. column |
| Quadratus Lumborum (bilaterally) | Fix the last rib during inhalation and forced exhalation |
| Splenius Capitis & Splenius Cervicis (unilaterally) | Rotate head/neck to same side, laterally flex head/neck |
| Splenius Capitis & Splenius Cervicis (bilaterally) | Extend head and neck |
| Internal Oblique (unilaterally) | Laterally flex vertebral column to same side, rotate vertebral column to same side |
| Transverse Abdominis | Compress the abdominal contents |
