Rectus Abdominus
Rectus Abdominus is the most superficial of the abdominal muscles. It is this muscle which forms the six-pack shape!
Origin
- Crest of the pubis.
- Pubic symphesis.
Insertion
- Xiphoid process (base of the sternum).
- 5th,6th and 7th costal cartilages.
Actions
- Flexes lumbar spine.
Innervation
- Ventral rami of thoracic nerves.
Daily uses
- Moving from lying to sitting.
Example strengthening exercises
- Crunches or sit-ups.
- Reverse crunch.
Example stretches
- Abdominal stretch.
Related injuries
- Abdominal strain.
Related muscles
- Internal obliques.
- External obliques.
- Transversus abdominus.
