Static and dynamic balance in ballet dancers: a literature review

Abstracts

A dança envolve integração de movimento, equilíbrio postural e aspectos relacionados ao controle postural. Informações sobre o equilíbrio em bailarinos são de grande importância, pois eles são considerados modelos de controle postural. O objetivo foi revisar estudos sobre equilíbrio postural estático e dinâmico em bailarinos, caracterizando o controle e a dependência visual desses atletas para a manutenção do equilíbrio. Para isso, foi realizada uma revisão nas bases de dados PubMed, SciELO, Lilacs e Science Direct, considerando o período entre 1997 a 2013, utilizando os descritores equilíbrio, controle postural, plataforma de forças, ballet, bailarinos clássicos e aferência visual. Foram selecionados 18 artigos capazes de fornecer dados quantitativos para avaliação do equilíbrio nesses atletas classificados pelo nível de evidência científica Oxford. A literatura revisada mostra completa concordância quanto ao efeito da retirada da informação visual sobre a estabilidade postural de bailarinos considerados como executantes altamente treinados. Estudos mostrando a comparação do equilíbrio de bailarinos com outras técnicas desportivas confirmaram um padrão específico de equilíbrio nesses indivíduos. Entretanto, associando-se à restrição visual, bailarinos apresentaram maior deslocamento do centro de pressão comparado a outras modalidades desportivas, sugerindo maior dependência visual para a manutenção do equilíbrio. Bailarinos apresentam menor oscilação postural em relação a indivíduos não treinados e indivíduos treinados em outras práticas desportivas, com maior dependência visual para manutenção do equilíbrio.

equilíbrio postural; dança; terapia pela dança

LITERATURE REVIEW

Static and dynamic balance in ballet dancers: a literature review

Equilibrio estático y dinámico en bailarines: revisión de la literatura

Michelle Silva da Silveira Costa^I; Arthur de Sá Ferreira^II; Lilian Ramiro Felicio^II

^IPostgraduate Program of Rehabilitation Sciences of UNISUAM – Rio de Janeiro (RJ), Brazil

Correspondence to

ABSTRACT

Dance involves integration between movement, postural balance and the multiple aspects involved with postural control. Information regarding the balance of ballet dancers is of great importance, as they are considered models of great postural control. The aim was to review studies about static and dynamic postural balance of ballet dancers, characterizing visual dependency in the postural control of these athletes to maintain balance. A review of literature was performed on PubMed, SciELO, Lilacs, and Science Direct databases considering the period between 1997 and 2013, and using the descriptors balance, postural control, force plates ballet dancers, classical ballet dancers and visual afferences. Eighteen articles were considered able to provide the quantitative and qualitative data to assess the balance among those athletes, and were thus, selected. These papers were classified by Oxford level of evidence. The reviewed literature shows full consensus regarding the effect of removing visual information over postural stability according to the experience of subjects considered highly trained dancers. Studies comparing the balance of ballet dancers to other sporting techniques confirmed that they have a specific postural balance pattern. Nevertheless, in association with visual restriction, ballet dancers show a greater center of pressure dislocation and instability compared to other sports, which suggests that they have higher visual dependence to maintain balance. Ballet dancers have better static balance compared to non-trained subjects and other types of athletes, but greater visual dependence to maintain balance.

Keywords: postural balance; dance; dance therapy.

RESUMEN

La danza envuelve integración de movimiento, equilibrio postural y aspectos relacionados al control postural. Informaciones sobre el equilibrio en bailarines son de gran importancia, pues ellos son considerados modelos de control postural. El objetivo fue revisar estudios sobre equilibrio postural estático y dinámico en bailarines, caracterizando el control y la dependencia visual de esos atletas para la manutención del equilibrio. Para eso, fue realizada una revisión en las bases de datos PubMed, SciELO, Lilacs y Science Direct, considerando el período entre 1997 y 2013, utilizando los descriptores equilibrio, control postural, plataforma de fuerzas, ballet, bailarines clásicos y aferencia visual. Fueron seleccionados 18 artículos capaces de proveer datos cuantitativos para evaluación del equilibrio en esos atletas clasificados por el nivel de evidencia científica Oxford. La literatura revisada muestra completa concordancia en cuanto al efecto de la retirada de la información visual sobre la estabilidad postural de bailarines considerados como ejecutantes altamente entrenados. Estudios mostrando la comparación del equilibrio de bailarines con otras técnicas deportivas confirmaron un estándar específico de equilibrio en esos individuos. Entre tanto, asociándose a la restricción visual, bailarines presentaron mayor desplazamiento del centro de presión comparado a otras modalidades deportivas, sugiriendo mayor dependencia visual para la manutención del equilibrio. Bailarines presentan menor oscilación postural en relación a individuos no entrenados e individuos entrenados en otras prácticas deportivas, con mayor dependencia visual para manutención del equilibrio.

Descritores: equilibrio postural; danza; terapia por la danza.

INTRODUCTION

Ballet is a physical activity that requires musculoskeletal conditioning by the use of complex high impact movements, with major joint amplitude, which works on the development of coordination, balance and laterality associated with efficient strength and flexibility in technical execution¹.

Postural control is important to understand the capacity of the human being to perform their activities and maintain body balance, providing stability and orientation during motor tasks². Such control depends on sensory information of the vestibular, visual and somatosensory systems, so that motor actions can be triggered based on experiences and skills^3-5. One determining factor for balance control is the size of the support base, and the movements executed by the ballet dancer are usually performed on a small base, such as the en pointe balance⁶ (Figure 1A). This movement involves major weight discharge at the tip of the foot, besides being more unstable and depending on ligaments and muscles for stability and support⁶.

Balance training begins early for dancers, around the age of five, and becomes more complex when they perform en pointe⁶, however, balance is rarely analyzed within the context of dance⁷. Training is conducted in the vertical position, with reduced support bases and the use of mirrors, and the direction of the eyes is important to keep control during spins, which implies visual dependency in order to maintain balance when compared to athletes of other sporting activities⁸.

Some studies used stabilometry to quantify the dislocation of the center of pressure (CoP) during orthostatic posture⁹, and they demonstrated that visual restriction limits postural control patterns, thus increasing postural oscillations^10,11. The common interpretation of the stabilometry suggests that postural tasks with higher values of parameters deriving from stabilometric signals are related to postural instabilities¹². Another important aspect in stabilometric tests is the possibility to identify the visual dependency of the individual, characterized by higher values of these parameters when vision is restricted during a motor task, such as more oscillation speed and longer distance crossed by the CoP¹².

The dynamic balance of ballet dancers was assessed by a few authors, and the execution of spins (pirouette) was considered as a complex task, involving a strategy of head movement, the "marking the head", which dissociates the rotation of trunk and head — while the body spins, the eyes stare at an established point, and when the maximal cervical rotation is reached, the head performs a fast rotation towards the same direction of the movement, and then the eyes stare at the same point again; therefore, it is possible to observe the importance of visual information for balance and quality of the motor performance during the spin, correlated to less postural oscillation^8,13-17.

Considering that the analysis of static and dynamic balance of ballet dancers, in the main moves, is very important for their performance, besides collaborating with the elaboration of training and rehabilitation programs for these athletes, the objective of this study was to review scientific literature concerning balance in ballet dancers, by observing if specific training would lead to less postural oscillation and to more visual dependency in order to control balance.

METHODOLOGY

A literature review was performed with the following databases: Lilacs, Medline, PubMed, SciELO and Science Direct, with the descriptors: ballet dancers, postural control, balance, force platform, classic ballet and visual afference, combined in groups of three. The pre-selection inclusion criteria of the articles were: date of publication (1997-2013), language (English or Portuguese) and the relation of title and abstract with the subject of interest (ballet and balance). The articles identified in the pre-selection search were assessed according to the following inclusion criteria: (1) population (ballet dancers) and (2) intervention (assessment of static or dynamic balance).

Review was carried out in three stages. In the first one, there was a general selection of publications on the subject, resulting in 57 studies. In the second stage, those which were duplicated and did not belong to the theme were excluded — the 18 remaining articles were included in the review and grouped together according to the year of publication, being selected based on the abstract. In the third stage, these articles were classified according to the recommendation criteria and evidence-based classification from the Oxford Centre for Evidence-Based Medicine (OCEBM)^18,19. Due to the low classification of the selected articles, the level of classification was not used as a selection criterion. The OCEBM levels consider the strength of evidence for therapeutic effect and damage, evidence of prevalence, accuracy of diagnostic tests, prognosis, therapeutic effects, rare damage, common damage, and are used as screening in review studies¹⁸.

RESULTS

The 18 articles selected for this study are presented in Table 1, describing sample, objective, tools used to assess balance, synthesis of results and Oxford classification^18,19.

DISCUSSION

The studies included in this review mostly presented (83%) sample size between 8 and 45 dancers, and 11% of the articles ranged from 4 to 8 dancers. With that, it is possible to observe the difficulty to perform studies with larger samples, probably due to the level of expertise and training of these athletes. Because of the number of articles discussing specific movements of professional dancers, especially those related to dynamic balance, these articles were included in this review despite the low sample, level of evidence 3–4 and recommendation B (little satisfactory).

Stabilometry was the most used method to assess static balance (55.5%). However, a major variation was observed as to positions and time of permanence on the force platform for the static balance evaluation according to CoP variables and anterior-posterior and medial-lateral dislocation areas, thus characterizing the balance of dancers by means of these variables.

The difficulty of the balance task increases with unipodal support, and this position is common for the ballet practice²⁰, considered to be of easy execution with good reliability^21,22. Therefore, considering specific positions of classic ballet, 27% of the articles assessed the static balance in specific unipodal postures^{6,10,11,20,23-28}. Lobo da Costa et al.²⁹ assessed ballet dancers in several demi-point positions (Figure 1B), wearing ballet slippers and barefoot, being the use of ballet slippers the cause for more dislocations of the CoP in all of the positions. Bruyneel et al.¹⁰ also found a much smaller dislocation area in similar conditions when the free limb was turned backwards (attitude derriére), in conditions with vision^29,30. Barcellos and Imbiriba²³ verified, by means of kinetics, the angular variations of pelvis, hip, knee and ankle joints, and, together with the mean speed of CoP oscillation, they observed a smaller dislocation area in the en pointe position than in a position with total plantar support.

The oscillating platform and the accelerometer (33% of the articles) were used to compare dynamic balance in relation to different visual conditions and different positions, among individuals grouped as to age and sex^{8,15,17,21,31}. It was observed that male professional dancers (>18 years old) with more practice time presented more visual dependency on a bipodal support over a mobile platform in comparison to younger male dancers (<18 years old)¹⁵, as well as women (>18 years old), because under the same conditions they presented smaller CoP area than the men³¹; according to the authors, the relationship between balance and gender would be related to the different movements performed by the dancers during a technical execution, in which men perform rougher and more explosive movements, while women perform more contained and soft moves.

Besides, male ballet dancers seem to be more dependent on their vision than female dancers^{6,15,21,31,32}, due to differences related to maturity and the development of the vestibular system, which takes place at the age of 9 and 10 years old among women, and 13 and 14 years old among men³³.

Kiefer et al.³⁴ also assessed female ballet dancers during a static task, with the objective of identifying differences in postural coordination between professional dancers and controls, who were not trained during a dynamic visual follow-up task by means of a electrogoniometer, thus verifying the ankle and hip angular oscillations while the athlete searches for the target³⁴. Since dancers are trained to look for reference points during gesture movements, they presented more control, as well as more stable hips and ankles when compared to controls³⁴.

The balance of ballet dancers in comparison to athletes of other sporting activities, such as judo wrestlers, runners, acrobats and soccer players, was discussed in 28% of the selected articles, and the dancers' high balance pattern without visual restriction was consensual, probably related to the specificity of the training for these athletes^{10,11,20,21,26,27,31}. However, 61% of the articles did not control the position of the upper limbs of the athletes^{6,7,10,11,15,17,24,27,29,32,34}; therefore, dancers could have taken the first rank for the upper limb, thus improving balance in the different assessed positions.

However, when assessing balance in association with visual restriction, ballet dancers presented a larger CoP dislocation in comparison to judo wrestlers, acrobats and non-athletes^11,31, thus pointing out to the major visual dependency of ballet dancers to maintain balance. On the other hand, Schmitt, Kuni and Sabo ²⁶ indicated that ballet dancers presented less postural oscillation in relation to athleticism. However, they assessed nonhomogeneous groups as to age, time of profession, gender, gestural and analyzed position.

According to Kiefer et al.³⁴, the difficulty to compare dancers with different groups of athletes is due to the fact that there are diversities not only concerning the different types of bodies, but also distinct training.

Despite the increased postural oscillation, other parameters should be taken into account to determine the efficacy of postural control, such as kinematics and kinetics. In relation to dynamic control, no studies comparing the specific activities of ballet with other sport modalities were found, nor those analyzing different types of dancers. Besides, assessing the visual dependency for balance during gestures of other modalities is important to understand the specificity of training for balance.

According to the selected articles, it is possible to observe moderate or unsatisfactory level of recommendation, thus, studies using different control groups, which can monitor the positions of lower limbs, different support bases and different gestural movements, can contribute with the evaluation both of the static and dynamic balance of these athletes.

Based on the used articles, we understand that ballet provides better balance in relation to non-trained groups and in relation to other sport modalities, which leads to better body stability³⁴, however, the visual dependency to maintain balance seems to be more present among dancers. Besides, it is possible to observe a relationship between sports training and postural oscillation, therefore, inserting balance exercises in the training of ballet dancers without emphasizing visual fixation could increase the postural control of these athletes.

Data in this study point out the increased oscillations among ballet dancers with visual deprivation in relation to other populations of athletes. Given the importance of balance for the performance of movement in classic ballet, it is important to explore different situations in dancing gestures, exploring its specificities. When postural control and balance is improved, producing more coordinated and coherent movement patterns, the probabilities of lesions could be reduced due to the presence of strategies of preprogrammed movements.

So, in order to better understand balance, it is important to emphasize aspects of the ballet dancer's gestures, and also work with a more homogeneous sample.

CONCLUSION

In literature, it was consensual that ballet dancers presented better static balance in relation to non-trained individuals and athletes of different sport modalities, however, dancers presented more visual dependency in order to maintain static balance due to the specificity of their training.

REFERENCES

• 1. Thiesen T, Sumiya A. Equilíbrio e arco plantar no balé clássico. Conscientiae Saúde. 2011;10(1):138-42.
• 2. Soares AV. A contribuição visual para o controle postural. Rev Neurocienc. 2010;18(3):370-79.
• 3. Carvalho RL, Almeida GL. Aspectos sensoriais e cognitivos do controle postural. Rev Neurocienc. 2009;17(2):156-60.
• 4. Mann L, Kleinpaul JF, Mota CB, Santos SG. Equilíbrio corporal e exercícios físicos: uma revisão sistemática. Motriz Rev Educ Fís. 2009;15(3):713-22.
• 5. Teixeira CS, Lemos LFC, Lopes LFD, Mota CB. A influência dos sistemas sensoriais na plataforma de força: estudo do equilíbrio corporal em idosas com e sem queixa de tontura. Rev CEFAC. 2010;12(6):1025-32.
• 6. Cheng-Feng L, I-Jung L, Jung-Hsien L, Hong-Wen W, Fong-Chin S. Comparison of Postural Stability Between Injured and Uninjured Ballet Dancers. Am J Sports Med. 2011;39:1324-31.
• 7. Picon AP, Lobo da Costa PH, Sousa F, Sacco ICN, Amadio AC. Biomecânica e Ballet Clássico: Uma avaliação de Grandezas dinâmicas do "sauté" em primeira posição e da posição "en pointe" em sapatilhas de ponta. Rev Paul Educ Fís. 2002;16(1):53-60.
• 8. Golomer E, Bouillette A, Mertz C, Keller J. Effects of mental imagery styles on shoulder and hip rotations during preparation of pirouettes. J Mot Behav. 2008;40:281-90.
• 9. Vieira TMM, Oliveira LF. Equilíbrio postural de atletas remadores. Rev Bras Med Esporte. 2006;12(3):135-38.
• 10. Bruyneel AV, Mesure S, Paré JC, Bertrand M. Organization of postural equilibrium in several planes in ballet dancers. Neurosci Lett. 2010;485(3):228-32.
• 11. Perrin P, Deviterne D, Hugel F, Perrot C. Judo, better than dance, develops sensorimotor adaptabilities involved in balance control. Gait Posture. 2002;15(2):187-94.
• 12. Raymakers JA, Samson MM, Verhaar HJJ. The assessment of body sway and the choice of the stability parameter(s). Gait Posture. 2005;21:48-58.
• 13. Denardi RA, Ferracioli MC, Rodrigues ST. Informação visual e controle postural durante a execução da pirouette no ballet. Rev Port Cien Desp. 2006;8(2):241-50.
• 14. Di Fabio RP, Emasithi A. Aging and the Mechanisms underly head and postural control during voluntary motion. Phys Ther. 1997;77(5):458-75.
• 15. Golomer E, Crémiex J, Dupui P, Isableu B, Ohlmann T. Visual contribution to self-induced body sway frequencies and visual perception of male professional dancers. Neurosci Lett. 1999;267(3):189- 92.
• 16. Imura A, Yeadon MR. Mechanics of the Fouetté turn. Hum Mov Sci. 2010;29(6):947-55.
• 17. Golomer EME, Gravenhorst RM, Toussaint Y. Influence of vision and motor imagery styles on equilibrium control during whole-body rotations. Somatosens Mot Res. 2009;26(4):105-10.
• 18. Phillips B, Ball C, Sackett DL, Badenoch D, Straus S, Haynes B, et al. Oxford Centre for Evidence-based Medicine Levels Evidence. 2001. [cited 2012 Sep 12].. Available from: http://www.cebm.net/index.aspx?o=1025
• 19. Pereira AL, Bachion MM. Atualidades em revisão sistemática de literatura, critérios de força e grau de recomendação de evidência. Rev Gaúcha Enferm. 2006;27(4):491-98.
• 20. Emery CA. Is there a clinical standing balance measurement appropriate for use in sports medicine? A review of the literature. J Sci Med Sport. 2003;6(4):492-504.
• 21. Guillou E, Dupu P, Golomer E. Dynamic balance sensory motor control and symmetrical or asymmetrical equilibrium training. Clin Neurophysiol. 2007;118(2):317-24.
• 22. Bläsing B, Calvo-Merino B, Cross ES, Jola C, Honisch J, Stevens CJ. Neurocognitive control in dance perception and performance. Acta Psychol (Amst). 2012;139(2):300-8.
• 23. Barcellos C, Imbiriba LA. Alterações posturais e do equilíbrio corporal na primeira posição em ponta do ballet clássico. Rev Paul Educ Fís. 2002;16(1):43-52.
• 24. Cheng Feng L, Fong-Chin S. Ankle biomechanics of ballet dancers in relevé en pointé dance. Res Sports Med. 2005;13(1):23-35.
• 25. Simmons WR. Neuromuscular responses of trained ballet dancers to postural pertubations. Int J Neurosci. 2005;115(8):1193-203.
• 26. Schmitt H, Kuni B, Sabo D. Influence of Professional Dance Training on Peak Torque and Proprioception at the Ankle. Clin J Sport Med. 2005;15(5):331-9.
• 27. Gerbino PG, Griffin ED, Zurakowski D. Comparison of standing balance between female collegiate dancers and soccer players. Gait Posture. 2007;26(4):501-7.
• 28. Chockley C. Ground Reaction Force Comparison Between Jumps Landing on the Full Foot and Jumps Landing en Pointe in Ballet Dancers. J Dance Med Sci. 2008;12(1):5-8.
• 29. Lobo da Costa PH, Nora FGSA, Vieira MF, Bosch K, Rosenbaum D. Single leg balancing in ballet: Effects of shoe conditions and poses. Gait Posture. 2012;15 [Epub ahead of print]
• 30. Aberg AC, Thorstensson A, Tarassova O, Halvorsen K. Calculations of mechanisms for balance control during narrow and single-leg standing in fit olders adults: A Reliability study. Gait Posture. 2011;34(3):352-57.
• 31. Golomer E, Dupui P, Monod H. Sex-linked differences in equilibrium reactions among adolescents performing complex sensorimotor tasks. J Physiol Paris. 1997;91(2):49-55.
• 32. Rein S, Fabian T, Zwipp H, Rammelt S, Weindel S. Postural control and functional ankle stability in professional and amateur dancers. Clin Neurophysiol. 2011;122(8):1602-10
• 33. Steindl R, Kunz K, Schrott-Fischer A, Scholtz AW. Effect of age and sex on maturation of sensory systems and balance control. Dev Med Child Neurol. 2006;48:477-82.
• 34. Kiefer AW, Riley MA, Shockley K, Sitton CA, Hewett TE, Cummins-Sebree S, et al. Multi-segmental postural coordination in professional ballet dancers. Gait Posture. 2011;34:76-80.
• 35. Golomer E, Philippe D, Sereni P, Monod H. The contribution of vision in dynamic spontaneous sways male classical dancers according to student or professional level. J.Physiol. 1999, 93:233-237.
• 36. Cheng HS, Law CL, Pan HF, Hsiao YP, HU JH, Chung FK, et al. Preliminary results of dancing exercise on postural stability in adolescent females. Kaohsiung Journal of Medical Sciences. 2011, 27:566-572.

Publication Dates

• Publication in this collection
  01 Nov 2013
• Date of issue
  Sept 2013

History

• Received
  Oct 2012
• Accepted
  Aug 2013