Every movement starts from the trunk: your core. You core is the base for any movement in the rest of your body. For example, when you start moving your arm up, you need enough tension in your core to create a stabilized base for your shoulder to move. Daily movements and training exert a lot of forces within your body every day. To absorb these forces, you need core stability: a stabilized trunk. It is a very important system in the body. So, let’s find out more about core stability.
What is Core Stability?
Core stability is a very popular term but what does it mean? The core is a term for all the stabilizing muscles of the spine. It is like a corset that protects the spine. All the muscles between neck and hips relate to your spine. A distinction is made between local and global stabilizing muscles. The global stabilizing muscles are multi-joint muscles located below the surface of the body. The local stabilizer muscles are very small single-joint muscles located deeper inside the body and closer to the spine.
Core Functions
The core has several functions. Very importantly, it protects the spine and nerve roots. But of course, it is also used to carry loads. It creates a stabilized base for the upper and lower limbs to move. And it helps use energy as efficiently as possible. But the core muscles are not the only stabilizing system. To explain the stability system of the core and the rest of the body we use the theory from White & Panjabi.
Core Stability – Panjabi Theory
Stability is not just a matter of your core but also of other body parts. To explain the term stability we use the Panjabi theory. Panjabi describes stability in 3 subsystems:
- The passive musculoskeletal subsystem includes vertebrae, facet joints, intervertebral discs, spinal ligaments, and joint capsules. Components of the passive subsystem (for example ligaments) do not provide any significant stability to the spine in the neutral position. It is toward the ends of the ranges of motion that the ligaments develop reactive forces that resist spinal motion. In a neutral position, the passive components probably function as transducers (signal-producing devices) for measuring vertebral positions and motions.
- The active musculoskeletal subsystem consists of the muscles and tendons surrounding the spinal column (the local and global stabilisers). The muscles and tendons of the active subsystem are the means through which the spinal system generates forces and provides the required stability to the spine. The magnitude of the force generated in each muscle is measured by the force transducers built into the tendons of the muscles.
- The neuromuscular and feedback subsystem consists of the various force and motion transducers, located in ligaments, tendons, muscles, and the neural control centre. It transports important feedback of body positions, loads and joint angles to the brain and gives correcting information back to the active stabilizing system to make adaptations to external forces.
Core Stability – Injuries
If one of these three subsystems does not function well it can lead to acute or chronic problems. A problem in the passive system may be caused by mechanical injury such as overstretching of the ligaments. The injury may result from overloading of a normal structure or normal loading of a weakened structure. This will lead to a decrease of the load-bearing and stabilizing capacity of the passive subsystem. And it may require compensatory changes in the active subsystem.
Problems in the active subsystem could be caused by overloading the system. If the active subsystem cannot handle the load it will result in a disfunction of the structure. The neuromuscular subsystem is very important for information processing. The active and passive system cannot function without receiving correct information from the brain and vice versa.
An injury does not always lead to trauma. In fact, overloading is a bigger problem! But why does this give you pain? Let’s look at the three subsystems again. The passive system cannot be trained much. The transducers relay information to the brain but you cannot really influence it much. If it does not work well, you need to compensate for it with other sub systems, like the active system.
Training Your Core Stability
The active system consists of moveable body parts, like muscles. You can train this sub system and make it strong enough to compensate a passive sub system. But this takes time. The muscles need to adapt to the new load. So, how can we get faster results? By training the neuromuscular system.
You can train this system by performing controlled and correct movements with the trunk. It is not always about heavy weights and fast movements. Controlling a movement you make with your trunk is harder than you may think.
While performing a heavy deadlift you take a deep breath and lock your core by holding your breath. You will use your global stabilisers to do that. But those muscles cannot do that all day long. The local stabilisers go from one vertebra to another. They are very small and do not generate a lot of power. And it is very hard to use them correctly. Additionally, you need them all day long to correct your body position and to adapt to external forces. They consist of a type of muscle fiber that can be active on low intensity for a very long time. This is a very effective system protecting your back from injury, but it is hard to use.
That is why we recommend to start training carefully. Make sure to perform each exercise correctly. Do not start doing as many reps as possible but start with perfect form. While using perfect form, you can focus on stabilizing all your body parts. Once you learn the perfect form you can start increasing reps and weight. But remember, perfect form comes first!
Take Home Message
Core stability is a very popular term in training, but a lot of people do not know how it works or how to train it. There are three sub systems involved in stability: the passive, active and neuromuscular system. To get the most out of your core stability system, you need to make the active system (the muscles) strong enough to handle external forces. In addition, the neuromuscular system needs to be on point to control every single muscle movement, especially by the local stabilisers. Careful practice will help increase your control and core stability.
Sources
- Vincent Huang et al. Spinal Instability: Definition, theory and assessment of spinal column function and dysfunction. American Academy of Physical Medicine and Rehabilitation. https://now.aapmr.org/spinal-instability-definition-theory-and-assessment-of-spinal-column-function-and-dysfunction/ November 2016.
- Manohar M. Panjabi. The Stabilizing System of the Spine. Part I. Function, Dysfunction, Adaptation, and Enhancement. JOURNAL OF SPINAL DISORDERS & TECHNIQUES. https://www.tigraheerenveen.nl/wp-content/uploads/2017/11/16-The-Stabilizing-System-of-the-Spine.-Part-I.-Funct.pdf August 1992.
- Elwin den Dulk. Core stability. Masseurs netwerk Nederland. https://masseursnetwerk.nl/core-stability/ June 2020.
