The Core, anatomy, functions and postural dysfunctions.


When I decided to write this article, I immediately realized that dealing with the topic in depth would have taken a really long time.

However, given its importance and my personal interest in it, I decided that it would be worthwhile to dig deeper into a compartment that holds great importance in movement, both in daily life activities, and in particular in Fitness and Sports.

People who usually frequent Fitness centers and, above all, the operators in the sector, should pay more attention to “Mr. Core”, because countless and highly important movement dynamics depend on, and are commanded by, it.

I am aware that, nowadays, people do not enjoy reading very much, so probably few of you will be interested in getting to the end of this article; for those who do, I hope it meets your expectations and, above all, you can get some interesting ideas from it.


“Anatomically speaking”…

Question: What is the Core?

Answer: Abdominals.

Wrong answer! Or rather, incomplete answer.

Besides being incomplete and, therefore, inaccurate, it would be an understatement to consider the Core as just “abs”.

We know that in popular thinking, the rectus abdomini is incorrectly considered as being the abdominals: the rectus is the muscle compartment that originates from the xiphoid process and from the fifth and seventh costal cartilage into a descending course down to the pubic symphysis.

Popular thinking aside, though, we need to specify that the musculature that includes the anterior portion of the trunk is made up, along with the rectus abdomini, by the internal and external obliques, that are superficial or external; there exists, however, also an internal unit that includes the transverse abdominis, the pelvic floor and the diaphragm.

That’s not everything, however, because the Core also includes the rear compartment of the trunk, also bringing into play the multifidus, the longissimus dorsi, the quadratus lomborum, the latissimus dorsi, the gluteus maximus, the scalenes (anterior, medius and posterior) and the erectors spinae. In its specific dynamic of contraction, the Core triggers their simultaneous and total activation.

Stuart McGill (Waterloo University, Canada), one of the leading experts and researchers in lumbar spine studies, states that to understand what the Core is made of and how it works, you can imagine the body without arms and legs contained by a bodice wrapping it like a big, narrow belt.

From the orthostatic position, if you place one hand on your navel and the other one on your lumbar muscles, you can feel how, from a voluntary contraction of the former, there is a consequent identical activation of the muscles in the posterior compartment, highlighting how the system works simultaneously.

This is co-contraction and co-activation of the two compartments: while training, you need to pay the same attention to both, and avoid overloading the front one, getting an imbalance of forces that can lead to an incorrect positioning of the pelvis, with consequent paramorphism, especially while in retroversion.

This last statement introduces something that I always deal with during the TRX Rip Trainer instructor course: as a matter of fact, the tool – made up of an elastic resistance bound by only one side of a bar – rotates and compels you to be “aware” while using your pelvis in its entirety, with the aim of exploiting its total dynamism to produce a fast, precise and controlled rotation while at the same time counteracting the occurrence of injuries to the lumbar spine area.

To achieve optimal proprioception of this anatomical part, pelvic mobilization exercises associated with proper breathing may be necessary. I have often noted that the compartment is blocked especially in individuals of an android biotype, and prevents even simple control in ante/retroversion.

To understand the importance of the Core, we will now analyze its main characteristics and functions, and then review the main postural problems – paramorphism – concerning the area.

This central muscular area where all the ascending and descending forces meet has the primary task of managing its “impetus” sometimes derived from exploding movements, instability, or lack of balance, that occur both in sports and in daily life; motor patterns always include the Core and therefore its stability, strength and sensitivity always translate into increased performance for two reasons: 

1. the movement may require less energy, as it increases control and coordination;

2. the risk of injury decreases considerably.

Throws in athletics, punches and kicks in martial arts, rotations in swimming, shots in golf, tennis and volleyball are just examples to understand how important the Core is in sports.

At the same time in everyday life, all the movements lead back to a management of the Core: from taking the grocery bags out of the car, to moving a closet.

From these examples, we can understand that one of the main functions of the Core is the distribution of the forces conveyed in that part by the set of muscles that compose it.

The transfer capacity that the power of a movement has, therefore, is linked to an anatomical/functional efficiency of the apparatus in question: I am thinking, for instance, about snatches in weight lifting, where the work of the kinetic chain is greatly facilitated by a strong, powerful, compact Core.

In the initial phase of the snatch, the athlete is crouched and, after grabbing the barbell, s/he performs an exploding extension of the lower limbs bringing the barbell up to shoulder height with a single movement; at this point s/he slips under the barbell with the weight over their head and their arms stretched up in an crouch; now, stretching their legs, s/he will return to a standing position.

It is easy to imagine how every single muscle in such a movement can be important: in this case, the Core always helps the action both as an agonist-synergist, and as a stabilizer in the intermediate phase of the movement. A weak core would probably not allow the athlete to maintain the correct curvatures of the dorsal spine, especially during the lift off phase.

From a purely anatomical point of view, the bodice that is formed is mainly intended to contain and protect the internal organs and the spine by making the system compact; the same muscles contribute to maintaining a correct posture.

In addition to the mere aesthetics, a correct posture leads to adequate management of the movement, improving the motor patterns and contributing to the correct interaction between the body districts joined in the chain.

The muscles that contribute significantly in guaranteeing the movement are those of the external unit: the internal muscles, joined to form a rectangle, act more in the stabilization phase and in low frequency regimes. The multifidus that runs along the spine is the long side of the rectangle; it meets at the top with the diaphragm to form the upper-short side; the same muscle meets the long side opposite the multifidus, constituted by the transverse abdominis. The base is the pelvic floor.

To obtain a highly performing movement, the passage of energy, coordinated at an intra-muscular and intra-district level, should not be “spoiled” – allow me – by incorrect positioning/re/tractions, either osteoarticular or muscular; also, the muscles of the inner region should preserve the characteristic of anticipating the movement, i.e. activating before the movement even begins, and being a stability mechanism, adequate to assist the true motor action of the exterior.

In addition to the correct correlation between the internal and external compartments, the correct arrangement of a “standard” posture – where the column has normal curvatures, the position of the pelvis is “neutral”, the lower limbs in an alignment ideal to support the upper compartment – offers many advantages in terms of quality of control of the tool or the movement.

In sports, quality (of movement or tool) is synonymous with performance.

A correct posture allows us to make the most of the energy we can develop without wasting even one Joule, making the most of what the nervous system has assimilated through the constant repetition of movement and stimuli: training.

The goal is to achieve the highest performance with minimum energy expenditure.

What are the main postural defects due to the wrong positioning of the pelvis? How and why do they occur?

Given the importance of posture and control of the Core in movement, we will now analyze the main paramorphisms we can find in which the position of the pelvis plays a fundamental role.

Kypho-lordotic/hyper-lordotic posture: in this case, the marked anterior pelvic tilt determines a reduction of the angle between the pelvis and the thigh in the anterior area, causing the hip to flex; this leads to a hyper-lordosis at the lumbar level and, in most cases, a hyper-kyphosis compensating the dorsal area.

Often, this type of paramorphism occurs due to a shortening of the iliopsoas muscle, which fixes on the last lumbar vertebrae and inserts itself into the small trochanter of the femur, creating a rotational force on the sagittal plane, leading to a forward inclination of the pelvis, sometimes associated with a strong lumbar muscle which contributes to the increase in the anterior inclination.

Flat back posture: in this case, the pelvic inclination is posterior so the pelvis is in retroversion; the hip joints extend and the lumbar region flattens. This is often caused by a strong abdominal compartment and short hamstrings that assist in “dragging” the pelvis to retroversion.

Sway-back posture: by observing a person on the sagittal plane with this type of posture, it is possible to notice how the head is positioned forward, the person usually has a long dorsal kyphosis with a flattening of the lumbar area; the pelvis is inclined posteriorly.

In this case, the muscles of the lumbar region are as strong as the hamstrings and the upper fibers of the internal oblique, which are also shortened.


The Core is the fulcrum of movement: training it correctly should be a priority both for the athlete and for the average fitness lover.

If there is something that should be clear from this article on the Core, it is that the exercises designed to stimulate this fascinating compartment need to include compound movements, rotations, flexions and/or extensions, isometries, small and large stimuli to always activate the SYSTEM.

Francesco Vetri

Wellness Escapes® Co founder