Original Article

Electromyographic Comparison of the Développé Devant at Barre and Centre

M. Virginia Wilmerding, Ph.D., Vivian H. Heyward, Ph.D., Molly King, M.D., Kurt J. Fiedler, M.D., Christine A. Stidley, Ph.D., Stuart B. Pett, M.D., and Bill Evans, M.F.A.

Abstract viding by their respective maximum raditionally, classical dance This investigation compared the elec- voluntary contraction (MVC). A four- masters formulated ballet tromyographic (EMG) activity of selected way ANOVA was used to assess the ef- T techniques at a time when muscle groups of skilled dancers execut- fects and interactions of subjects, tri- kinesiological and biomechanical ing the développé devant at barre and in als, phases, and “treatment” (barre concepts were at best primitive, and centre. A four-channel Nicolet-Viking versus centre). Results indicated no sig- often erroneous. As a result, Biomedical electrograph system was used nificant difference (p < 0.05) between misconceptions became part of the to assess muscular activity. Surface elec- barre and centre for either the quadri- tradition of didactic ballet training trodes were placed over four muscles: ceps femoris or hamstring muscle of the and tended to be passed down as quadriceps femoris, hamstrings, tibialis gesture leg. The main effect of phase critical aspects of the master’s artistic anterior, and abductor hallucis. The par- was significant (p < 0.05). There was a ticipants performed five trials of the significant difference in EMG activity insights. A problem associated with développé devant at barre and centre in (p < 0.05) between barre and centre for these inchoate scientific principles randomized order. The dancers per- the tibialis anterior and abductor may be the potential for increased formed the six phases of the développé hallucis of the standing leg across susceptibility to injury and decreased devant (coupé, passé, attitude, full exten- phases. Post-hoc analysis indicated that aesthetic performance.1 sion, tendu, closure to fifth position) in EMG activity of the tibialis anterior Electromyography has been used time with a metronome set in three-quar- and abductor hallucis muscles was sig- to examine the traditional theoretical ter time at 144 beats per minute. EMG nificantly greater at centre compared to models and movement metaphors amplitude was recorded at each of the six barre during all phases of the développé promoted universally by ballet in- time phases (1200, 2400, 3600, 4800, devant. It was concluded that the train- structors. The specific aspects of bal- 6000, and 7200 msec, respectively). The ing at barre is an acceptable way of pre- let movements that have been stud- EMG values (mV) of the raw amplitude paring the muscles of the gesture leg, ied using EMG include the grand of each phase of the développé devant for but not the standing leg, for the de- 2 each subject were “standardized” by di- mands of centre. battement or high kick, the demi- plié,3,4 and the grand-plié,5,6 as well as complex dance sequencing.7 Kine- M. Virginia Wilmerding, Ph.D., and Vivian H. Heyward, Ph.D., are at the siological studies such as these are Center for Exercise & Applied Human Physiology, University of New Mexico, deemed imperative to the safe and Albuquerque, New Mexico. effective teaching of ballet.1,8-11 Fur- Molly King, M.D., Kurt J. Fiedler, M.D., and Stuart B. Pett, M.D., are at the ther, empirical measurement aimed at Veterans Administration Medical Center, Albuquerque, New Mexico. determining the effectiveness of tra- Christine A. Stidley, Ph.D., is in the Department of Family & Community ditional training techniques has been Medicine, University of New Mexico, School of Medicine, Albuquerque, New identified as an important component Mexico. of the field of dance science.11 An essential aspect of the warm- Bill Evans, M.F.A., Department of Theatre & Dance, University of New Mexico, up period of a ballet class is the sup- Albuquerque, New Mexico. port device known as the barre. The Correspondence and reprint requests: M. Virginia Wilmerding, Ph.D., Center for techniques of ballet that are executed Exercise & Applied Human Physiology, University of New Mexico, Albuquerque, at the barre are broken down into New Mexico 87131. small, accessible, and repeatable

69 70 Journal of Dance Medicine & Science Volume 5, Number 3 2001 movements. By placing one or both ments practiced in a ballet class is the which can take 25% to 50% of class hands on the barre, the dancer is pro- développé devant. This requires time, actually prepares the artist to vided in effect with a “partner.” After standing on one leg while pulling the dance in centre. The purpose of this the techniques are practiced there, the gesture leg into the extreme ranges of study was to compare the electromyo- dancer proceeds to centre and repeats hip flexion while maintaining exter- graphic (EMG) activity of selected these techniques in increasingly com- nal rotation (Fig. 1). This is referred muscle groups of skilled dancers ex- plex fashions without hand support. to as “extension.” Dancers are highly ecuting the développé devant at barre There is a presumed positive transfer regarded if, in their “extension,” they and in centre. The quadriceps femo- of training when moving the dancer are capable of lifting their leg abnor- ris and hamstrings on the gesture leg from the barre to centre. The exer- mally high. Traditionally, lifting one’s were chosen because of the pervasive cises practiced with hand support leg from underneath provides the use in classroom settings of the afore- during warm-up are meant to facili- dancer with an metaphorical image of mentioned metaphor that is possibly tate the execution of the same move- lightness and a weightlessness of the incorrect. In addition, the muscles of ments without physical support. The gesturing leg.12 Scientific models, us- the lower leg and foot showed the transfer of training from barre to cen- ing mathematical concepts to assess greatest variance in EMG measure- tre is undocumented. It is unknown the direction of muscle pull, point of ments in pilot work on balance man- if the muscular movements at barre application, and co-contraction com- agement, and thus were chosen as the are similar enough to be appropriately ponents, might disprove this idea.13 muscles to be measured formally on assigned as positive transfer, or dis- It is possible that the développé devant the standing leg to shed light on the similar enough to cause a negative causes the greatest confusion among differences between barre training and transfer. If the latter is the case, the dancers faced with what they are told centre dancing. warm-up at barre may be eroding, or to do by their teacher and what they, at least interfering with, dancing abil- in fact, feel occurring within their own Materials and Methods ity. bodies. Further, it is unknown Subjects and Electromyographic One of the more complex move- whether the warm-up period of barre, Arrangement Eighteen professional and advanced pre-professional female dancers (aged 18 to 45 years) were invited to par- ticipate as a convenience sample on a volunteer basis. Potential participants were screened to ensure that they had been in training a minimum of 10 years, were currently taking class regu- larly, and were actively performing. Further, each subject had to be free of injury or orthopaedic disorders that could potentially compromise their performance. The research was ap- proved by the Human Subjects Re- view Board of the Veterans Adminis- tration Medical Center. Prior to testing, each participant received a complete explanation of all proce- dures and written informed consent was obtained. The participants were tested in the Electromyography Labo- ratory at the Veteran’s Administration Medical Center in Albuquerque, New Mexico. Measurements were taken in an enclosed room in which the tem- perature and humidity were con- trolled at a comfortable level. The participants wore a leotard with no tights. Ballet shoes were not worn. Figure 1 Développé devant (left to right): A, Phase 1 – Coupé; B, Phase 2 – Passé; A four-channel Nicolet-Viking C, Phase 3 – Attitude; D, Phase 4 – Full Extension; E, Phase 5 – Tendu; F, Phase 6 – Biomedical (Madison, Wisconsin) Fifth Position. electrograph system was used to as- Journal of Dance Medicine & Science Volume 5, Number 3 2001 71 sess muscular activity. Surface elec- in EMG activity for the six phases of all subjects. However, most dancers trodes were placed on the gesture leg the movement. Based on this data, a were also skilled in other dance forms over the quadriceps femoris at the cen- sample size of 15 dancers was needed such as modern dance, tap, jazz, and tral aspect of the vastus lateralis, and to achieve a power of 0.80 for effect flamenco. Five of the 18 dancers in- over the hamstring muscles. Surface sizes of interest and a significance level dicated no dance training other than electrodes were also placed over the of 0.05. Ultimately, 18 dancers con- ballet. abductor hallucis and tibialis anterior sented to participate in this study. In addition, 78% of the dancers muscles of the standing leg. Electrodes These dancers represented nearly all engaged in other forms of exercise were placed as close as possible to the of the eligible dancers in the city, and such as cycling, stair-stepping, spin- centers of the fully contracted muscle thus, were not a random sample of a ning, aerobic dancing, simulated belly to obtain maximal EMG poten- large population. cross-country skiing, running, and tials.14 The skin surface was cleaned A mixed effects four-factor analy- lifting weights. On average, the sub- with alcohol and gently abraded to sis of variance (ANOVA) was used for jects spent 2.75 hours per week in maximize electrical conductance. each muscle group with subjects as a cross-training activities. Electrodes were affixed to the skin random effect (SAS-JMP, Thompson with Transpore™ tape. All measure- Learning, Florence, KY). The fixed Quadriceps Femoris Muscle of the ments were collected during one ses- effects were the phases of the Gesture Leg sion. développé devant (coupé, passé, atti- The EMG activity of the quadriceps Following a suitable warm-up and tude, full extension, tendu, and clo- femoris is illustrated in Figure 2. The practice period, the participants per- sure to fifth position), performed at “treatment” (barre versus centre) by formed the développé devant at barre two positions (barre and centre), over phase interaction was not significant and centre in a fully randomized or- five trials by 18 subjects. All two and (F5,340 = 0.95; p = 0.45). As expected, der. The dancers stood in fifth posi- three factor interactions of the fixed the main effect of phase was signifi- tion on a platform with an embed- effects were considered. The raw data cant (F5,340 = 582.53; p < 0.0001). ded signal switch underneath their underwent log transformation prior Tukey’s post-hoc pair-wise compari- right foot. Each trial began with the to statistical analysis in order to at- sons indicated that the amplitudes in dancer depressing the switch. The tenuate the effect of outliers. Tukey’s most phases were significantly differ- dancers performed the six phases of post hoc tests were used to detect sig- ent from each other. However, there the développé devant (coupé, passé, nificant differences among treatment, was no significant difference in EMG attitude, full extension, tendu, and phases, and trials. The experiment- amplitude of the quadriceps femoris closure to fifth position) in time with wise alpha level was set at p = 0.05. muscle between attitude and full ex- the audible and visual cue of a metro- tension (3600 msec and 4800 msec) nome set in three-quarter time at 144 Results and between passé and closure to fifth beats per minute. The full movement The descriptive characteristics of the position (2400 msec and 7200 msec). took 7.2 seconds to execute. The trial subjects are presented in Table 1. The was completed when the signal switch average age was 27.7 ± 7.21 years. Av- Hamstring Muscle of the Gesture was depressed again. erage height and body weight were Leg Hard copy output of the raw data 166.79 ± 5.13 cm and 54.84 ± 4.16 The EMG activity of the hamstrings was obtained following each repeti- kg, respectively. The subjects had on is presented in Figure 3. The “treat- tion. Amplitude was recorded at each average 20.3 years (range: 15 to 37 ment” (barre versus centre) by phase of the time segments that corre- years) of ballet training. The young- interaction was not significant (F1,340 sponded to the phases of the est a dancer had begun training was = 0.22; p = 0.64). As expected, the développé devant (1200, 2400, 3600, at 2 years of age; the oldest was 23 main effect of phase was significant 4800, 6000, and 7200 msec respec- years. On average, training in dance (F5,340 = 49.68; p < 0.0001). Tukey’s tively). Peak amplitude at each of began at 6.8 years of age. Ballet was post-hoc pair-wise comparisons indi- these phases was compared to a maxi- the predominant form of training for cated that the amplitudes in most mum voluntary contraction (MVC) that each dancer performed at the end Table 1 Descriptive Characteristics of Subjects of the testing period. MVC was iden- tified as the peak EMG amplitude a Mean SD Min Max dancer achieved in a ten-second trial Age (years) 27.7 7.21 18 44 of contraction against the imposed Height (cm) 166.79 5.13 157.5 176.5 external force of the technician. Weight (kg) 54.61 4.16 47.5 61.3 Age began ballet 6.81 4.86 2 23 Statistical Analysis Years of experience 20.3 5.52 12 37 Pilot studies were conducted on two Dance training (hrs/wk) 11.31 6.79 3 15.5 dancers and used to assess variability Other modes of training (hr/wk) 2.75 2.31 0 6 72 Journal of Dance Medicine & Science Volume 5, Number 3 2001

Figure 2 Average log ratio of peak EMG amplitude relative to Figure 3 Average log ratio of peak EMG amplitude relative to MVC of the quadriceps femoris muscle of the gesture leg during MVC of the hamstring muscle of the gesture leg during phases phases of the développé devant. of the développé devant.

Figure 4 Average log ratio of peak EMG amplitude relative to Figure 5 Average log ratio of peak EMG amplitude relative to MVC of the tibialis anterior muscle of the gesture leg during MVC of the abductor hallucis muscle of the gesture leg during phases of the développé devant. phases of the développé devant. phases were significantly different Tibialis Anterior Muscle of the way interactions were significant (p > from each other. The significant pair- Standing Leg 0.05). wise comparisons included the EMG The EMG activity of the tibialis an- Abductor Hallucis Muscle of the amplitude of coupé and all the other terior is illustrated in Figure 4. The Standing Leg phases of the movement. In addition, “treatment” (barre versus centre) by significant pair-wise comparisons phase interaction was significant The EMG activity of the abductor were between passé and attitude (F5,340 = 2.31; p = 0.04). Tukey’s post- hallucis is presented in Figure 5. The (2400 msec and 3600 msec), passé hoc pair-wise comparisons indicated “treatment” (barre versus centre) by and tendu (2400 msec and 6000 that at each phase of the développé phase interaction was significant msec), attitude and full extension devant (coupé, passé, attitude, exten- (F5,340 = 2.34; p = 0.02). Tukey’s post- (3600 msec and 4800 msec), attitude sion, tendu, and closure to fifth posi- hoc pair-wise comparisons indicated and closure to fifth position (3600 msec tion), EMG amplitudes were signifi- that at each phase of the développé and 7200 msec), and full extension and cantly greater in centre as compared devant (coupé, passé, attitude, exten- tendu (4800 msec and 6000 msec). to barre. No other two-way or three- sion, tendu, and closure to fifth posi- Journal of Dance Medicine & Science Volume 5, Number 3 2001 73 tion), EMG amplitudes were signifi- msec), the knee of the gesture leg was full extension phase of the movement. cantly greater in centre as compared flexed to a mild degree to hold the At this point, the action of the ham- to barre. No other two or three way lower leg toward the medial malleo- string muscle would be expected to be interactions were significant (p > lus of the standing leg. As the leg was purely antagonistic. Therefore, the in- 0.05). drawn to passé (2400 msec), the crease in EMG activity may reflect co- quadriceps femoris displayed in- contraction of the antagonist, serving Discussion creased electrical activity, probably to decelerate and smooth the movement Quadriceps Femoris Muscle of the due to increased hip flexion and of the lower limb in full extension. Gesture Leg “cross-talk” of the rectus femoris. However, it is unlikely that this provides It was expected that the quadriceps During attitude, the leg was moved evidence that a trained dancer can ac- femoris muscle would display signifi- forward in the sagittal plane to a fur- tually “lift their leg from underneath,” cantly higher EMG activity when the ther increased degree of hip flexion. a metaphor used by many ballet instruc- développé devant was performed The thigh was held in place until the tors when teaching this movement. It is without external support in centre lower leg was fully extended. During simply not mechanically or anatomically compared to at barre. Although the this time, EMG activity decreased correct to suggest that a muscle can push moment of force requirements of the slightly. As the leg was lowered to a limb. knee and hip joint would not be dif- tendu, the diminished hip flexion was ferent, it was expected that lack of revealed by a lower electrical signal. Tibialis Anterior Muscle of the external support would generally re- In closure of the gesture leg back to Standing Leg quire all muscles to work harder to the starting point of fifth position, the It was expected that displacement of maintain balance. This hypothesis was relative EMG activity diminished fur- the body posteriorly must occur to not borne out by this research. Each ther. counterbalance the movement of the dancer showed a great range of rela- gesture leg anteriorly and away from tive electrical activity during the Hamstring Muscle of the Gesture the center of gravity when initiating course of the movement, but gener- Leg the développé devant. Presumably, ally, the pattern was homogeneous It was additionally expected that the this displacement would generate and nearly identical when comparing hamstring muscle group of the ges- greater relative electrical activity in- the overall average results between the ture leg would display a significantly dicating increased effort by the tibi- two “treatments.” Furthermore, it was higher signal on average when the alis anterior of the standing leg to expected that the muscular demand développé devant was performed at maintain an upright stance in centre. of extending the gesture leg from at- centre as compared to barre. It, too, While this hypothesis was supported, titude to full extension would be was expected to assist in balance con- it should be noted that at each phase greater in centre. trol. In fact, no difference was ob- of the développé devant, the relative The quadriceps femoris muscle served between these two treatments. EMG activity of the tibialis anterior group consists of four muscles with The muscle did show, on average, in centre exceeded that of the tibialis one segment, the rectus femoris, cross- similar peak activity during the passé anterior at barre. This was unex- ing both the hip and the knee joints. as compared to closure to fifth posi- pected; it was presumed that the As such, it serves as both a hip flexor tion. movement of the gesture leg away and a knee extensor. The electrodes To establish the passé, the ham- from the center of gravity would in- were placed in such a way as to cover string must actively contract to draw duce higher relative EMG activity in the belly of the vastus lateralis, which the lower leg and position the foot the anterior tibialis. This implies that is not a hip flexor. Yet, with the ex- near the knee joint as the hip increases standing on one leg unassisted re- pected “cross-talk” aimed to pick up in flexion. During closure to fifth, the quires more muscle activity from the the four-part muscle group as a whole, hamstring must also contract to draw tibialis anterior muscle to maintain an the quadriceps femoris’ primary role the thigh back to neutral position upright stance; the positioning of the as a knee extensor did not display a from flexion. However, not all of the gesture leg is of less consequence. heightened electrical signal at these dancers made use of the knee flexor- two points in time. In fact, in nearly hip extensor muscle in this manner. Abductor Hallucis Muscle of the half of the subjects, the signal actu- One-third of the subjects did not dis- Standing Leg ally diminished between these two play an increase in EMG activity as The abductor hallucis is a very small phases of the développé devant. the passé was executed, and more than intrinsic muscle that runs superficially The significant main effect of one-quarter did not exhibit increased along the medial border of the foot. phase reflected the changing require- hamstring activity as the leg was It originates on the calcaneus and in- ments of the quadriceps femoris closed to fifth position. serts on the medial side of the base of muscle throughout the course of the It was interesting to note that there the phalanx of the great toe. Its ac- développé devant. At the initial point is a rise in EMG activity of the ham- tions are abduction and flexion of the of measurement, the coupé (1200 string muscle from the attitude to the great toe. Although diminutive, it is 74 Journal of Dance Medicine & Science Volume 5, Number 3 2001 clearly of great importance in main- gesture leg with no apparent displace- and biceps femoris during the “demi- taining an upright stance at centre. ment of the center of gravity or vis- plié” in dance [abstract]. Med Sci- Standing on one leg unassisted re- ible movement of the rest of the body. ence Sport Exerc 15:S159, 1983. quires relatively greater muscle activ- Theoretically, use of the barre assists 4. Trepman E, Gellman RE, Solomon ity of the abductor hallucis muscle; in the training of this skill. However, R, Murthy KR, Micheli LJ, DeLuca the positioning of the gesture leg is of the results from this study indicated CJ: Electromyographic analysis of standing posture and demi-plié in less consequence. that the abductor hallucis is highly in- ballet and modern dancers. Med Sci- volved during the fine alterations that ence Sport Exerc 26(6):771-782, Conclusions occur on the standing leg, and as such, 1994. The développé devant is one of the may not be well served by extensive 5. Clippinger-Robertson KS, Hutton most difficult movements performed training at barre. The same holds true RS, Miller DI, Nichols TR: Me- at barre. It is usually performed near for the tibialis anterior muscle. In con- chanical and anatomical factors re- the end of the barre exercises. Histori- trast, it appears that the gesture leg is lating to the incidence and etiology cally, a great deal of misinformation well served by the ritual of beginning of patellofemoral pain in dancers. In: has been passed to the dancer con- ballet class with external support, and Shell CG (ed): The Dancer as Ath- cerning the role of the major muscles moving to independent and more lete: The 1984 Olympic Scientific complex actions later in the class pe- Congress Proceedings. Champaign, IL: of the gesture leg – the quadriceps Human Kinetics Publishers, Inc., femoris and the hamstring muscle riod. 1986, pp. 53-72. groups – in the execution of this most It is unlikely that the tradition of 6. Trepman E, Gellman RE, Micheli important skill. The exact nature of barre will ever be removed from the LJ, DeLuca CJ: Electromyographic their role in the creation of a smooth format of a ballet class. The implica- analysis of grand-plié in ballet and and aesthetically pleasing développé tions of this research, however, speak modern dancers. Med Science Sport devant has not been quantified prior to the responsibility of the teacher and Exerc 30(12):1708-1720, 1998. to this study. student of dance in recognizing the 7. Chatfield SJ: Electromyographic re- Initial pilot work focused on the limitations of using the barre for ex- sponse of dancers to isokinetic work hip region of the standing leg as ternal support. The value of using the and select dance movements. Kine- well. However, in viewing the re- barre appears to be more appropriate siology and Medicine for Dance for training the gesture leg than the 16(1):60-82, 1993. sponses of a variety of standing leg 8. Cardinal MK, Hilsendger H: A cur- muscles, it appeared that the lower standing leg. As such, the dependence ricular model for dance wellness edu- limb and foot muscles showed the on the apparatus should be de-empha- cation in higher education dance greatest amount of variance and the sized, the duration of barre should be programs. J Dance Med Sci 1(2):67- greatest amplitudes throughout the minimized, and the training of the 72, 1997. phases of the développé devant. standing leg in centre should be more 9. Clippinger KS: Standards and certi- Hence, the tibialis anterior and ab- greatly emphasized in ballet classes. fication for the dance instructor. J ductor hallucis muscles were chosen Dance Med Sci 1(2):44-45, 1997. to represent the changing muscular Acknowledgments 10. Krasnow DH, Chatfield SJ: Dance science and dance technique class. demands placed on the standing leg The authors would like to thank the Vet- when performing the développé erans Administration Medical Center for Impulse 4(2):162-172, 1996. 11. Clarkson PM, Skriner M: Science of the use of their facility and equipment. devant at barre and centre. Dance Training. Champaign, IL: The ballet dancer attempts to We would additionally like to thank Jerome Sarason for illustrating and Human Kinetics, 1988, pp. 17-22. maintain the utmost stillness of the 12. Lawson J: Teaching Young Dancers. Cristine Mermier for assisting in the col- torso in executing any given skill. New York:Theatre Arts Books, 1979, lection of data. However, the body is not capable of p. 79. true and absolute stillness; even with 13. Hammill J, Knutzen KM: Biome- the greatest concentration and intent. References chanical Basis of Human Movement. Gentle swaying always occurs during 1. Howse J: The importance of good Baltimore:Williams & Wilkins, upright stance as agonist and antago- teaching in injury prevention. Med 1995, p. 410. nist muscles interact in a reflexive and Probl Perform Artists 9(2):32-34, 14. Zuniga EN, Truong XT, Simons complex manner to establish and sus- 1994. DG: Effect of skin electrode place- 15 2. Ryman RS, Ranney DA: A prelimi- ment on averages electromyographic tain any given posture. potentials. Arch Physical Med Re- Additionally, the isolation of ges- nary investigation of two variations of the grand battement devant. hab 51:264-272, 1970. ture limb movement is of great con- Dance Research Journal 11(2):2-11, 15. Enoka EM: Neuromechanical Basis of cern in dance training. This is par- 1979. Kinesiology. Champaign, IL:Human ticularly true in adagio or slow 3. Ferland G, Gardiner PF, Lebe-Neron Kinestics Publishers, Inc., 1988, pp. movements such as the développé RM: Analysis of the electromyo- 143-144. devant. The dancer aims to move the graphic profile of the rectus femoris