The concept and specific work of the Core or middle zone is increasingly widespread and widespread, not only among physiotherapists but also in the field of health, prevention and rehabilitation of injuries at the lumbo-pelvic level and in the world of preparation fitness and sports performance optimization. A series of basic concepts about the Core and its importance are presented in this article.
What is the Core?
Core is a word that in English means center or nucleus. It is located in the center of gravity of the body, from where all the movements of the functional kinetic chains start. Its operation is based on a correct balance of length, strength and neuromotor patterns of all the kinetic chains that will allow efficient acceleration, deceleration and lumbopelvic stabilization during movements; that is to say: the muscles of the Core help to generate and transfer the necessary force from the larger segments to the smaller ones of the body during the activities and movements of the same. Which is formed by 29 pairs of muscles whose insertions are located there.
What elements make up the Core?
The Core or lumbopelvic stability nucleus is made up of three subsystems, and their integrity determines the efficiency of the CORE. These systems are:
Also called Form Closure. They are those structures that lack contractile capacity but help the joint stability of the entire lumbopelvic belt. It is made up of bones, joints/joint surfaces, joint capsule, ligaments, cartilage, and discs. These structures determine the joint balances and the type of movement and allow a certain degree of quite limited loads to be supported.
Also called Force Closure. It is composed of the core muscles, the tendons and the fasciae, that is, the contractile elements. The muscular subsystem is necessary not only to provide greater loads, but also to be able to perform exercises with resistance and dynamic activities.
There are many muscles that make up the Core, but we are going to name the main muscles below:
1. Transversus abdominis muscle
It is one of the main stabilizers of the sacro-iliac joint. The more stabilization required, the greater degree of contraction of the muscle is achieved. The main function of this muscle is to create tension on the thoraco-lumbar fascia in its bilateral contraction. It is also associated by co-contraction with the diaphragm, pelvic floor and multifidus. It has a direct relationship between the decrease in its thickness at rest and the appearance of pathologies related to the pubis.
2. Diaphragm Muscle
It is a main muscle of the body that has two clearly differentiated functions. The first is a respiratory function whose balance is agonist-antagonist with the abdominal muscles. The second is a stabilizing function, synergistically with the abdominal muscles.
It has a direct relationship with abdominal tone and postural control that translates into an improvement in the symptoms of low back pain simply with the improvement of diaphragmatic respiratory function.
3. multifidus muscle
Obliquely oriented postural muscles located in the vertebral column have attachments to the deep layers of the thoracolumbar fascia. They maintain lordosis and segmental stability within the neutral zone. Its neuromuscular activation is identical to that of the transversus abdominis and its activation is essential for the stability of the Core.
4. pelvic floor muscles
Very important for the stabilization of the lumbopelvic girdle, especially in the anteroposterior balance. They also support the abdominal content and have a great role in urinary and fecal control. It coactivates alongside the transversus abdominis to stabilize the symphysis pubis, S1 joints, and pelvis.
5. quadratus lumborum muscle
Muscle that links the motor activity of the vertebrae having a large lever arm through the transverse processes and has insertions in the rib cage and in the pelvis.
6. internal oblique muscle
Muscle whose activity is very similar to the transversus abdominis and many of its fibers are parallel to it. It is included in the core stabilizer system or lumbopelvic belt due to its many insertions in the thoraco-lumbar fascia.
It is in charge of responding to the variations detected and carrying out lumbopelvic corrections, either in sudden situations or organizing compensatory patterns. It is in charge of adjusting the entire body as a whole, receiving information from the passive and active system.
If there is a dysfunction or alteration of a subsystem, the person will be predisposed to lumbar injuries and non-specific lumbar pain, as well as poor performance in sports.
Emotions and the core
Altered emotional states are capable of altering the postures adopted, determining changes in muscle activation patterns, making them less effective in stabilizing and increasing compression and torsion forces on the spine and pelvis.
Situations of stress and anxiety produce alterations in the motor programs of the transversus abdominis and have repercussions on the core. Both chronic and musculoskeletal pain modulate neuromotor activity in more or less the same way, altering the gait pattern. Correct stabilization with correct lumbo-pelvic-femoral neuromotor patterns are essential in the etiology of low back pain.
Why and for what use the Core concept?
The use of the CORE concept is necessary for a good prevention of injuries since if we take into account that the majority of sports gestures and activities of daily life are three-dimensional movements that require both strength and balance of the trunk in the three planes, an alteration of these factors will result in an inefficient technique that will predispose to injuries, one of the clearest examples is low back pain that occurs in sports that require rotation with flexion-extension and repetitive direction changes.
More efficient fiber recruitment of the core musculature with faster nervous system activation is known to improve motor unit synchronization; Several studies have reported that a lack of strength and resistance in the stabilizing muscles of the trunk and pelvis together with an altered recruitment pattern are associated with muscle and joint injuries of the spine and lower limbs.
Therefore, if we are able to stabilize, re-educate and strengthen our CORE we will be able to anticipate injuries or improve rehabilitation and recovery times both at a functional and sports level.