Looking for the Core Part 2 – Core Stability to Movement Control

Back to the future – part 2: The second part of Lincoln Blandfords blog looking at core stability.

This week we conclude last week’s blog on the rise and fall of the core stability (CST) concept. Part one chronicled the ascent of CST, its reinterpretation by different practitioners to suit their own needs (high or low threshold) and the criticisms that this process of dissemination ultimately led to. Functional training or neuromuscular training had taken the place of CST, (even though it looked remarkably similar). It seemed the high threshold, ‘train like an athlete’ approach had won the day.

Movement unites

In 2015, and helping to restore the balance between the high and low intensity approaches to movement quality is the migration of strength and conditioning professionals towards the world of sports rehabilitation. Tasked with the long term management of athletes, the need to understand the working practices of the rehab professionals they operate alongside has opened the motor control, low threshold door again. Equally, physiotherapists, progressing the sub-elite performer back to competition are recognising the job is only half done with low intensity is the only weapon in the arsenal; physios are upskilling in performance training.

Informed on the application of low intensity biased, movement control, contemporary S&C professionals can now supply movement focussed programing across the entire movement control continuum, from the lowest to the highest threshold of muscle recruitment. The physio can now supply low threshold, pain mediating approaches and then progress in to high threshold performance work. The old CST debates of low or high, hollow or brace are slowly resolving themselves out of necessity for what works. Low threshold is back on the menu and the movement control continuum is again broad.

Movement answers to movement questions

Within my own journey, The Performance Matrix movement analysis system has supplied many answers, a systematic, evidenced based approach, acting as a lighthouse in the CST-functional training storm. The system’s ability to asses and retrain movement at both low and high intensity solved the question of motor control or core strength; both are required, but we need to know when. The specificity of the system allowed the performance of seemingly non-functional exercises to be easy to defend to my doubting colleagues and peers; each exercise is addressing specific physiology in a way to reverse a deficit before its put back into an improved, working whole. The cognitive testing of movement control allowed for the development of the concepts of movement health and the possession of choice in individual’s movement outcomes; if you can’t prevent a movement occurring during a test, you have lost movement options, movement choices. Movement control was the

The book concludes the chapter with the following paragraph “Let’s thank CST for all it brought to light, but get on with putting movement at the heart of performance and injury prevention.” (Looking for the core? Finding movement control, 2015)

Everything or nothing?

Within the collective conscious of fitness and beyond, core training and injury prevention have become entwined. This relationship has been bolstered by wealth of academic literature reporting the effective use of core training in reducing injury occurrence (Caraffa et al., 1996; Fitzgerald et al., 2000; McGill et al., 2003; Myer et al., 2004; Paterno et al., 2004). So, if core training works, what actually is it? Today, that omnipresent term ‘core stability’ mercurially slips through the fingers of those seeking to easily define it. In some quarters its very existence is doubted (Lederman, 2009), a perspective contrasted to those who have long seen it as a cornerstone of their discipline (Pilates) and the body as a whole (STOTT, 2012).

A brief history

It used to be so simple. Exercisers used to work their abs, pursuing aesthetics in the main, strong was good, muscular fatigue essential, feeling was believing. Then, things changed…

The late 1990s saw a shift in terminology, understanding and beliefs on how to train the trunk. The continued high prevalence of low back pain led research to inquire into the relationships between this condition and the roles of the abdominal and low back musculature (Hodges & Richardson, 1996). Findings were interpreted and disseminated across the globe, crossing disciplines, beyond the clinical to the sporting, from the peer reviewed to the mass media. Core stability was born, grew up, ‘got famous’.

In more recent times authors such as Willardson (2007) have observed the roles of personal trainers, physiotherapists, and strength and conditioning coaches increasingly merging, yet, within these professions, the application of, and beliefs behind core training vary enormously. The continuum presented below is galactic in scale. At one end, almost imperceptible muscle contractions performed in the clinical setting must be contrasted to the conditioning coaches’ maximal strength workouts at the other. All claim to work the core.

The current continuum

The mass media helps cloud the issue, tapping into baser sentiments such as achieving an ‘attractive core’, a superficial perspective in all senses of the word. Sports commentators confidently pronounce on the world’s number one tennis player’s ‘strong core’, arbitrarily linking performance to a concept born out of therapeutic research.

Core training has a problem, an identity crisis. Applied to so many situations, a victim of its success, has it lost its meaning? Brooks (2012) strongly questions the validity of the whole approach, stating ‘athletes are probably wasting their valuable training time including core training in their routines’. Although less damning the Reed paper (2012) suggests core training is effective; though only for some. Differing outcomes and opposing perspectives can be explained through an exploration of what is meant by core training throughout the continuum and across the numerous movement based disciplines. A search for common ground leads us to consider interpretations of the ‘core’ itself. This quest for shared principles seeks to unite contemporary applications of core training from the rehabilitative to the performance focussed. Ultimately, it desires a shift in perceptions and an embracing of contemporary perceptions on movement and movement control.

Core quest- what is the core?

Something’s core, the central or most important part (Faries & Greenwood, 2007), is a description revealing both a locality and a significance. Laptop computers have a core. Their manufacturers, eager to promote their product, set much store in the qualities of this internal hardware. Agreement upon a definitive location of the ‘hardware’ of the core of ‘core training’ is hard to find. For some, this will always represent the internally located musculature of the low back region, for others, the term encompasses the entire trunk including the pelvic and shoulder girdles (Comerford & Mottram, 2012). These regions are layered in the exerciser’s tools of influence, muscles. Muscles produce, slow down, and limit unwanted movement (both gross & subtle). Training can develop these qualities through the manipulation of strength (high force/structural focus), endurance (sustained effort focus) and skill related (co-ordination) variables.

Core components- Hardware focus

It is apparent certain trunk muscles have been highlighted as playing certain roles more effectively than others (Sahrmann, 2002), based upon their anatomical and physiological properties. As exercise intensity changes, all muscles will be effectively required to play their respective roles to differing degrees, a viewpoint that supports a core comprised of the entire trunk’s hardware, from the deepest to the clearly visible. This allows exercise intensity to be a means to influence training outcomes, placing bias on certain muscles, peeling off or layering on muscular contributions until the correct strategy is found to bring about the desired effect, upon the desired structure.

Influential contributors such as McGill (2001) also emphasise the importance of differentiating training of the hardware, forwarding a separation of core endurance from core strength outcomes when considering injury occurrence. The hardware approach, typically favoured by those from a strength training background, does represent some of the demands of daily living as both strength and endurance are routinely required. As the level of challenge tends to vary throughout a day and between individuals, movement must be controlled in many ways, a variety representative of the core training continuum (subtle to gross). Both strength and endurance are sometimes the answer to a movement challenge ‘question’, yet frequently another element is also required to be the dominant factor challenged in exercise.

Core components- Software focus

The core’s hardware is made ‘smart’ by a ‘controller’; the nervous system. In good movement health, a highly interdependent blend of passive (bones & joints) and active hardware (muscles) operate effectively under the control of this software (Panjabi, 1992). Providing a constant internal conversation the software allows all components to ‘talk and listen’ to one another, a discourse that aims to efficiently meet the challenges of the day. Just like the hardware, this software and its language are also open to persuasion; it can be upgraded through effective training (Tsao & Hodges, 2008). Software biased training often called ‘motor control’ has been typically favoured by those from a rehabilitative background. One function of the software, and central to movement health, are effective patterns of ‘recruitment’ (Briggs et al., 2004). The ‘controller’ must efficiently choose which particular muscles to employ, at which point in time and how much each will contribute to any given task. Hodges & Richardson (1996) have shown training can change the sequencing of the software, selecting some muscles preferentially to others. This discrimination of muscles requires a ‘software biased’ training focus.

Body mapping

The internal conversation also allows for a virtual body to ‘mapped’ out within regions of the brain; the software’s interpretation of the hardware’s form (Wand et al., 2011). In good movement health each section of the hardware is accurately charted, allowing for efficient movement control. In poor movement health certain regions can become over-represented, becoming the ‘squeaky wheel’, demanding excessive attention from the software’s controller. These regions of the body, constantly ‘moaning away’ may change this map, altering efficient navigation/negotiation of movement challenges as the individual makes their way through the world. In such cases a software upgrade is required, redrawing the map and taking the internal spotlight away those attention seeking players.

Unity

Uniting hardware and software biased training approaches allows for a gently graded spectrum to appear; a merging of those at the apparent polar opposites of the core training continuum, from the rehab to the sporting. No good and bad muscles, no redundant software, just the right hardware, employed at the right time, in the right amount, for the right reasons. All contributions and contributors accepted; everything in its right place.

Keep the concepts, lose the term

Helping establish this link between practitioners along a ‘core training continuum’ is a universal desire to control movement. If every time we heard or read ‘core training’ the words were replaced with ‘movement control’ the hardware or software bias debate may be defused and finally left behind. Core training is still jam packed with opposing perceptions and opinions almost religious in nature. The ‘what is the core’ debate may never arrive at an answer. The term ‘stability’ is often misinterpreted in two distinct ways; applied by some only to static exercises the stability of moving systems is ignored. Additionally, as evident in engineering models, exercise does not make the core ‘more stable’ but more robust to movement challenges; systems are either stable or unstable, as opposed to less or more (Reeves et al., 2007).

Moving & moving on           

Movement control, less catchy, but more embracive, spans the continuum between the clinical and the athletic, less loaded with polarising opinion, no ‘previous’. Further expanding the concept, work of Zazulak et al (2007) and Roussel et al (2008) has revealed how quality of movement control in the trunk also relates to injury occurrence in the legs. Movement control now relates to all body regions, removing the need to mention either the core (too confused) or stability (too confusing).

Contemporary usage of exercise within the movement control continuum requires choosing the correct exercise from its spectrum for the correct movement control fault- hardware or software biased. No wonder Brooks (2012) and Reed (2012) found core training to both time wasting in some cases and successful in others if the exercise chosen were randomly employed. Software can fix software, hardware addresses hardware. That movement control faults can be addressed with such specificity suggests the core debate may have proved worth having after all, if only to show how far we have since come.

Summary

The movement control concept this text promotes can be seen to have evolved out of numerous schools of thought. Spinal and trunk ‘stability’ were once the limits of its extent, whereas now the whole body can now be seen through the viewpoint of movement control at varying degrees of intensity. The next chapter considers the range of movement control challenges that must be managed so as to maintain/attain movement health.

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