The term “core stability” is used frequently in the media and fitness world and increasingly in dance training, but what does it actually mean for dancers and why do they need it?
The core is generally thought of as the centre of the body (the part between the sternum and the knees) and stability is about gaining control of the spine and pelvis to support torso movement and coordinate the action of the limbs. A good functional core helps to connect the upper and lower body in order to produce a refined and efficient dynamic alignment when dancing.
To engage the core effectively, dancers need to understand the relevant groups of muscles that are involved and the way they can be accessed. Sometimes instructional cues and execution are unfocused and dancers might spend a lot of time on supplemental exercises that are not as helpful in increasing their core stability as they could be. Dancers do not only need to know which muscles to locate but clear instruction on how to find them. Giving the direction simply to “use your core” in class is not very beneficial!
Rather than simply seeing the core as the front of the body (abdominals), it might be helpful to think of it as a cylinder, incorporating the back muscles and also the diaphragm at the top and the pelvic floor at the bottom. To stabilize the core requires a team of muscles, each one playing a role in organising and coordinating the body. “Global” muscles support mobility and effective orientation in the spine – these have been identified as the rectus abdominis, the lateral fibers of the external obliques, the psoas major and the erector spinae muscles. “Local” muscles, including the multifidi and the quadratus lumborum, help with inter-segmental stability because of their short length and their attachment to the vertebrae. Primarily, the transversus abdominis (TA), and the multifidi are seen as key, as they have been shown to be the first muscles to contract in order to stabilize the movement of an extremity, but through their connection to the thoracolumbar fascia, the internal obliques additionally contribute to the cylindrical support. The diaphragm and pelvic floor also play their part in spinal and pelvic stability while helping to reduce the strain on the abdominal and back muscles.
To improve the core, it is important to train all of the contributing muscles collectively – inefficient local muscles can cause compensation of the global muscles, negatively affecting overall stability. The local muscles must be able to maintain isometric contractions continuously, working at lower grade intensities, but in a coordinated way. For the general population, there are often recommendations made for sit-ups and crunches to improve the look of the abdominals (see the “ripped” six packs advertised by fitness magazines!). However, this emphasis solely on the superficial abdominals, using repeated flexion of the spine and hip joints when performing sit-up exercises can often lead to overwork and imbalance without achieving functional efficiency. Instead, it has been suggested that a combination of endurance, strength, power and proprioception training is the most effective way to achieve the synergetic motor patterns that will benefit dancers. This can be done using dynamic exercises that challenge balance and use resistance to maintain control against the disruption of stability.
SiDI says……
- While research suggests that core stability work is effective in enhancing general fitness and helping to prevent lower back pain, training should avoid exercises that place increased compressive loads on the lumbar spine.
- Be aware that an emphasis solely on the superficial abdominals can negatively affect the strength and flexibility relationship between the front and back of the torso, potentially leading to muscle imbalance and back pain.
- To work safely and effectively, dancers should avoid routinely engaging in overly strenuous abdominal workouts and instead try to identify the weaker links in their combined core musculature, both local and global, to gain better dynamic control.
Bibliography
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Behm, D.G. & Colado Sanchez, J. C. (2013). Instability resistance training across the exercise continuum. Sports Health, Nov, 5(6): 500–503.
Kline, J.B., Krauss, J.R., Maher, S.F. & Xianggui, Q. (2013). Core strength using a combination of home exercises and a dynamic sling system for the management of low back pain in pre-professional ballet dancers: A case series. Journal of Dance Medicine and Science, 17(1), 24-33.
Philips, C. (2005). Stability in dance training. Journal of Dance Medicine and Science, 9(1), 24-28.
Quin, E., Rafferty, S. & Tomlinson, C. (2015). Safe dance practice: An applied dance science perspective. Champaign, IL: Human Kinetics.
Sharrock, C., Cropper, J, Mostad, J., Johnson, M. & Malone, T. (2011). A pilot study of core stability and athletic performance: Is there a relationship? International Journal of Sports Physical Therapy, Jun; 6(2): 63–74.
Simmel, L. (2014). Dance medicine in practice: Anatomy, injury prevention, training. London, England: Routledge.
