Desired:

• Cylindrical abdominal activation + proportional eccentric contraction.
• Collar bones not lifted + chest kept in caudal position
• Lower ribs stabilised via oblique abdominal muscle chains.

Observe for:

1. Decreased abdominal tone
2. Lateral gorges in abdominal wall
3. Impaired respiration
4. Pseudohernia

A positive trunk curl up test reveals:

• A dominance of the hip flexors over weakened abdominal muscles.
• Minimal curling of upper trunk
• Anterior tilt of pelvis