Which muscle is NOT part of the Inner Core Unit according to the core description?

• A. Transversus Abdominis
• B. Pelvic Floor
• C. Multifidi
• D. Deltoid

Answer: (D)

The inner core unit consists of muscles that brace the spine from inside to provide stability during breathing and movement. Transversus Abdominis acts like a corset, increasing intra-abdominal pressure to stabilize the trunk. The pelvic floor supports the base of the core and coordinates with the abdominal muscles for spinal and pelvic stability. The multifidi are small deep back muscles that provide segmental stabilization of the lumbar spine. The deltoid, on the other hand, is a large shoulder muscle responsible for lifting the arm and does not contribute to spinal stability as part of the inner core. Therefore, the deltoid is not part of the Inner Core Unit.