Professional Dancers Research Articles

Preliminary study of bone biomarkers in elite female ballet dancers

Elite female ballet dancers are at high-risk of bone stress injuries (BSI) due to high-levels of weight-bearing exercise causing micro-cracks to form in the bone. The consistently high volumes of weight-bearing exercise may lead to a low BMI which reduces oestrogen levels by suppressing the gonadotrophin axis. The combination of high-levels of weight-bearing exercise and low oestrogen may be associated with increased bone remodelling. Investigating the relationship between exercise, BMI, oestrogen, and bone remodelling is crucial for developing prevention and management strategies for BSI. We conducted a pilot study of 4 weeks in a group of elite female professional ballet dancers and in female controls: the study subjects were monitored for self-reported weekly exercise, BMI, urinary oestrogen metabolites (2OHE1 and 16OHE1) and urinary NTX, a marker of bone resorption and proxy for remodelling. Measurements were collected at baseline, week 2 and 4. Dancers exhibited significantly higher hours of exercise per week (p = 0.004), and a BMI significantly lower (p = 0.030) than that of age-matched controls. In contrast, the levels of oestrogen metabolites (p = 0.050) and NTX (p = 0.460) were comparable in the two groups. Using NTX as a biomarker of bone remodelling, these results suggest that despite intense weight-bearing exercise, ballet dancers may not undergo higher bone remodelling than controls. The resulting insufficiency of bone remodelling may increase the risk of BSI because micro-cracks might accumulate in the bone faster than damaged tissue could be replaced. Based on these findings, larger studies will be designed to assess the effect of bone remodelling on BSI risk and recovery in professional ballet dancers, to develop a platform of prevention and treatment strategies including screening programmes to identify dancers at risk.

Psychological stress responses to a live performance by professional flamenco dancers.

Dance is a high demanding discipline that involves physiological and psychological pressures. The pressure increases when dancers perform in front of an audience that, on a physiological level, can generate hormonal responses similar to those of an athlete before a competition for social status. Low levels of testosterone (T) and high levels of cortisol (C) are related to a decrease in performance and an increase in the risk of injury. Therefore, this study sets out to analyse hormone response patterns in professional flamenco dance performances depending on whether the performances are completed successfully and whether there are differences by sex and professional category. Saliva specimens (2-5 ml) were taken from the participants before and after the performance. Samples were immunoassayed by duplicate to analyze momentary fluctuations in two hormones regularly used in studies with professional athletes. The results showed significant differences in solo dancers' T responses before and after the performance (p < 0.01), suggesting that the dancing role in the show (soloist or corps the ballet) and responsibility over the performance were important modulators to the hormone responses observed.

Human Motion Recognition in Dance Video Images Based on Attitude Estimation

With the deep integration of science and technology and culture, the estimation of human movements in dance video images will become an important application field of computer vision technology, which can be used not only for professional dancers’ movement correction, dance self-help teaching, and other application scenarios but also for athletes’ movement analysis. Therefore, it will greatly promote the implementation of teaching students in accordance with their aptitude by applying information technology to estimate dancers’ movements and postures in real time and obtaining information of classroom dance teaching status in time. In this paper, human motion recognition in dance video images is studied based on an attitude estimation algorithm. When the number of experiments reaches 20, the average value of deep learning algorithm and particle swarm optimization algorithm is 76.23 and 75.23, respectively, while the average value of attitude estimation algorithm in this paper is 77.95. Therefore, the average results of attitude estimation algorithm in this paper are slightly higher than those of other algorithms.

Prevalence of Asymptomatic Talar Bone Marrow Edema in Professional Ballet Dancers: Preliminary Data From a 2-Year Prospective Study.

Compared with symptomatic bone marrow edema (BME) associated with stress fractures, asymptomatic BME seen on magnetic resonance imaging (MRI) is a phenomenon that has been described in high-level athletes and is thought to be related to bone adaptation to biomechanical loading unique to each sport. However, the prevalence, natural history, and management of these lesions remain poorly understood, particularly in dance, which places tremendous stress on the feet and ankles. The purposes of this study were to (1) determine the prevalence of asymptomatic BME in the talus before the start of the performance season, (2) identify contributing demographic and training factors, and (3) compare the radiological evidence of talar BME with validated functional foot and ankle scores. We hypothesized that talar BME would be highly prevalent among asymptomatic professional dancers. Case series; Level of evidence, 4. A total of 14 professional ballet dancers (6 female and 8 male; mean age, 24 years) were included in this 2-year prospective study. For each participant, we recorded complete medical and surgical history along with scores on the Foot and Ankle Ability Measure (FAAM) and the Foot and Ankle Disability Index. Bilateral foot and ankle 3.0-T MRI scans without contrast were completed before the start of the performance season and were evaluated for BME of the talus using the Fredericson criteria. Evidence of talar BME was seen in 15 of the 28 (54%) ankles examined and in 9 of 14 (64%) dancers. We found that 6 dancers demonstrated bilateral talar BME, 3 dancers demonstrated unilateral BME, and 5 dancers demonstrated no evidence of BME. The most common location of BME was the posterior talus, seen in 8 of 15 (53%) ankles. No statistically significant differences were noted in dancers with versus those without talar BME with regard to functional scores, demographic characteristics, or weekly training hours. Asymptomatic talar BME was highly prevalent (64%) in professional ballet dancers and tended to occur posteriorly. Long-term clinical and radiographic follow-up is necessary to determine the natural history of these lesions.

‘Brexit put us in the Fridge, Covid in the Freezer’: The Impact of Covid-19 and Brexit on UK Freelance Dance Artists

This article investigates how Covid-19 and Brexit have impacted the practices, finances and wellbeing of UK dance professionals, drawing on first-hand data collected in early 2021 from interviews, questionnaires and a panel discussion. The testimonies of freelance practitioners from different backgrounds, as well as key stakeholders from national institutions and organisations employing or otherwise interacting with freelancers, present bottom-up insights from the scene. Our research project more specifically explored the ramifications of the pandemic and Brexit, and the impact of these crises on the diversity of the UK dance scene (broadly construed). The voices and findings presented are framed by a discussion of the economic and political infrastructure of the so-called ‘creative industries’ in the country, with particular attention to the freelance creative labour model, risk and precarity. The article concludes by proposing a politics of small resistive steps which might help to mitigate these challenges, working from within the dance ecosystem.

ACTING MASTERY

Contemporary dimensions of acting are analyzed in the article. The problem of teaching acting has always been relevant. The complexity of the subject lies in the fact that it is at the intersection of dramatic and choreographic art. There is a lot in common between them, and in many ways, ballet theater draws on the experience of drama theater. However, certain aspects show the fundamental difference between ballet theater and drama. That is why teaching the discipline "Theory and Practice of Acting" imposes specific requirements on educators: it is essential to know and understand the purpose and specifics of the laws of directing and dramaturgy of the drama theater. Moreover, it is equally important to know and understand the specifics of directing and dramaturgy of the ballet theater. In our opinion, an acting teacher should be a director, playwright, choreographer, and performer with practical stage experience at the same time. Acting skills in ballet theater, folk and pop dance, contemporary choreography, children's play dance, etc. are of fundamental importance. Creating images, the ability to convey feelings, thoughts, states, interaction with partners, and emotional communication with the audience - dance cannot exist without all of this. After all, dance, like art in general, is one of the means of communication between people, a way of interacting with the world. It allows one to manifest and express oneself, thoughts about reality, and one's place in it, both in the dance itself and during the training of professional dancers. Â

Creativity and Flow: Not a Simple Relationship

ABSTRACTIn this study, flow, both dispositional and state, and movement‐based creative processing were investigated in a group of pre‐professional and professional dancers (N = 288) who were involved in the creation, rehearsal, and performance of a new dance work(s). Dance is both movement‐based and group‐based. The Experience of Creativity Questionnaire and Dispositional Flow Scale were administered 2 weeks prior to the performance of the new choreography. The state flow data were collected immediately after the completion of the final dress rehearsal and immediately following the opening night performance. The results of this quasi‐experimental study demonstrated that the association with creative processes and dispositional flow dimensions yielded weak significance. Many creative processing dimensions predicted state dress and performance flow conditions, although the predominant predictors were Clarity and Preparation, Creative Anxiety (negative predictor), and Beyond the Personal. The uniqueness of this study was that it focused on movement‐based creative processing and its relation with dispositional and state flow.

Posturography measures in specific ballet stance position discriminate ballet dancers with different occurrences of musculoskeletal injuries

BackgroundThis study aimed to identify the postural sway variables that can distinguish between ballet dancers with high and low occurrences of musculoskeletal injuries. MethodsFourteen professional ballet dancers were assigned to a high-occurrence group (N = 5, reports >2 injuries in the previous 6-months) or a low-occurrence group (N = 9, reports ≤1 injury). Center-of-pressure (COP) data were acquired using a force platform during the following tasks: single-leg stance with eyes open, single-leg stance with eyes closed, and demi-pointe stance with eyes open. The COP standard deviation (SD) and range (RA) in both the medial-lateral (ML) and anterior-posterior (AP) directions were estimated. Between-group comparisons were made through Welch's t-tests for unequal sample size along the effect size measure (Cohen's d). Spearman's rho was used to estimate the association between the number of injuries and the COP variables. The statistical threshold was set at 1%. ResultsA between-group effect was found only for the demi-pointe stance, with large effects for SDML (P = 0.006, d = 1.7), RAAP (P = 0.006, d = 1.7), and RAML (P = 0.005, d = 1.7). An inverse relationship was found between the number of injuries and the demi-pointe's COP range in both directions (Spearman's rho from −0.681 to −0.726, P = 0.007). ConclusionsCOP measures taken in ballet-specific positions can distinguish between dancers with a high and low occurrence of musculoskeletal injuries. Suggestions are made to include ballet-specific tasks in the functional assessments of professional dancers.

Modeling Multiple Temporal Scales of Full-Body Movements for Emotion Classification

This work investigates classification of emotions from full-body movements by using a novel Convolutional Neural Network-based architecture. The model is composed of two shallow networks processing in parallel where the 8-bit RGB images obtained from time intervals of 3D-positional data are the inputs. One network performs a coarse-grained modelling in the time domain while the other one applies a fine-grained modelling. We show that combining different temporal scales into one architecture improves the classification results of a dataset composed of short excerpts of the performances of professional dancers who interpreted four affective states: anger, happiness, sadness, and insecurity. Additionally, we investigate the effect of data chunk duration, overlapping, the size of the input images and the contribution of several data augmentation strategies for our proposed method. Better recognition results were obtained when the duration of a data chunk was longer, and this was further improved by applying balanced data augmentation. Moreover, we test our method on other existing motion capture datasets and compare the results with prior art. In all of the experiments, our results surpassed the state-of-the-art approaches, showing that this method generalizes across diverse settings and contexts.

Let’s all dance: Enhancing amateur dance motions

Professional dance is characterized by high impulsiveness, elegance, and aesthetic beauty. In order to reach the desired professionalism, it requires years of long and exhausting practice, good physical condition, musicality, but also, a good understanding of choreography. Capturing dance motions and transferring them to digital avatars is commonly used in the film and entertainment industries. However, so far, access to high-quality dance data is very limited, mainly due to the many practical difficulties in capturing the movements of dancers, making it prohibitive for large-scale data acquisition. In this paper, we present a model that enhances the professionalism of amateur dance movements, allowing movement quality to be improved in both spatial and temporal domains. Our model consists of a dance-to-music alignment stage responsible for learning the optimal temporal alignment path between dance and music, and a dance-enhancement stage that injects features of professionalism in both spatial and temporal domains. To learn a homogeneous distribution and credible mapping between the heterogeneous professional and amateur datasets, we generate amateur data from professional dances taken from the AIST++ dataset. We demonstrate the effectiveness of our method by comparing it with two baseline motion transfer methods via thorough qualitative visual controls, quantitative metrics, and a perceptual study. We also provide temporal and spatial module analysis to examine the mechanisms and necessity of key components of our framework.

Adaptation to repeated standing-slips in professional ballet dancers

Ballet training is being increasingly used to improve physical functions in older adults. Our previous work showed that ballet dancers react to a novel standing-slip more effectively than their non-dancer counterparts through better control of the recovery step and trunk movement. The purpose of this study was to test if and to what extent ballet dancers adapt differently to repeated standing-slips relative to non-dancers. Protected by a harness, twenty young adults (10 professional ballet dancers and 10 age/sex-matched non-dancers) experienced five repeated and standardized standing-slips on a treadmill. Changes from the first slip (S1) to the fifth slip (S5) in dynamic gait stability (primary outcome) and other variables, including the center of mass position and velocity, step latency, slip distance, ankle angle, and trunk angle (secondary outcomes) were compared between groups. Results revealed that both groups adopted similar proactive controls to improve dynamic gait stability by using the ankle and hip strategies. However, dancers showed a better reactive improvement in stability after the repeated slips than non-dancers. From S1 to S5, dancers reactively improved their dynamic gait stability more than non-dancers at the recovery step liftoff (p = 0.003). Dancers decreased their recovery step latency (p = 0.004) and shortened the slip distance (p = 0.004) significantly more than non-dancers from S1 to S5. These findings suggest that ballet dancers could facilitate the adaptation to repeated slips, which may be attributed to their ballet practice experience. This finding augments our understanding of the underlying mechanisms of ballet practice reducing falls.

Dance-related musculoskeletal injury leading to forced time-loss in elite pre professional dancers – a retrospective study

ABSTRACT Young ballet dancers place themselves at risk of injury on a daily basis, often pushing their training beyond limits, ultimately leading to pain and injury. When signs and symptoms of injury are ignored, functional ability and overall health may be seriously compromised and absence from dance practice may forcibly take place. Objectives Describe the epidemiology of dance-related musculoskeletal injury leading to forced time-loss in elite pre-professional dancers and provide descriptive data on the prevalence concerning diagnoses, location, and injury type, stratified by gender and skill level. Methods Retrospective cohort, over a 3-year period on a full‐time pre-professional Portuguese dance school featuring 70 both gender students with a mean age of 14.87 years. A total of 110 injuries were analyzed. Non‐parametric statistics were used. Results The most prevalent diagnosis leading to forced time-loss in female dancers were Medial Tibial Stress Syndrome (MTSS), 14.29%, and Posterior Ankle Impingement Syndrome (PAIS), 7.14%, whereas in male dancers these were Hallux Sprain, 17.50%, and Lumbar Spine Joint Injuries, 7.50%. Differences were found in injuries’ anatomical location between genders and in Incidence Proportion and Clinical Incidence between skill levels. 72.20% of the chronic injuries and 50.00% of the acute injuries occurred in Level III students. Conclusions With respect to forced time-loss injuries, male dancers were found to sustain more acute traumatic injuries and female dancers overuse, respectively, sprains and MTSS and PAIS. Identifying which injuries are most likely to lead to forced time-loss may be useful for helping health-care professionals in clinical decision-making and in developing more effective injury prevention and management strategies.

Does Workplace Spirituality Increase Self-Esteem in Female Professional Dancers? The Mediating Effect of Positive Psychological Capital and Team Trust

Based on the self-transcendence theory and immaturity-maturity theory, this study empirically tested the influence of female professional dancers’ workplace spirituality on positive psychological capital, team trust, and self-esteem. The subjects of this study were female professional dancers. We conducted the surveys in two countries—the United States and the United Kingdom—and ultimately obtained 441 samples. To test the hypotheses, we performed a structural equation model analysis using three statistical programs: SmartPLS, GSCA Pro, and jamovi. (1) The workplace spirituality of female professional dancers showed a statistically significant positive influence on positive psychological capital, team trust, and self-esteem. (2) The positive psychological capital of female professional dancers showed a statistically significant positive influence on team trust and self-esteem. (3) The team trust of female professional dancers showed a statistically significant positive influence on self-esteem (except when using jamovi). This study found that fostering workplace spirituality was paramount for female professional dancers in an organization. Accordingly, we outlined four recommendations for the organizations: (1) convey the importance of the organization’s mission and values to organizational members; (2) increase each organizational member’s decision-making and autonomy; (3) encourage members to cooperate while working in the domains of their specific positions; and (4) discourage members from neglecting their organizational responsibilities and resorting to egoism.

Pain Perceptions, Suffering and Pain Behaviours of Professional and Pre-Professional Dancers towards Pain and Injury: A Qualitative Review.

Limited data exist that describe the experiences of pain and injury in dancers. The purpose of the current study was to understand pain perceptions, suffering and pain behaviours associated with pre-professional and professional dancers and to consider the psychosocial factors that influence suffering, behaviour and perceptions of pain. A thematic synthesis review was undertaken in three stages: (1) A systematic search using pre-defined search terms was conducted until 17 November 2022. Qualitative studies were included if they captured dancers' perceptions, experiences, or the behaviour of dancers towards pain and injury. (2) Quality appraisal and certainty assessments was performed. (3) A five-phase synthesis generated themes that included a certainty assessment score. Twelve studies with 290 dancers met the inclusion criteria. The aggregated mean age was identified as 28.5 years. No studies were excluded following the quality appraisal stage. Nine studies included professional ballet dancers. Three themes were developed: (1) developing positive and adapted perceptions and behaviours towards pain, (2) the impact and danger of embracing pain and the risk of injury and (3) factors that influenced the response to injury and the ability to perform. This review has highlighted the experiences of pre-professional and professional dancers towards pain and injury. Practical implications for healthcare professionals, employers, choreographers and dancers are provided. Further research is required given the limited evidence base.

The development and validation of an open-source accelerometery algorithm for measuring jump height and frequency in ballet

ABSTRACT The aim was to determine the validity of an open-source algorithm for measuring jump height and frequency in ballet using a wearable accelerometer. Nine professional ballet dancers completed a routine ballet class whilst wearing an accelerometer positioned at the waist. Two investigators independently conducted time-motion analysis to identify time-points at which jumps occurred. Accelerometer data were cross-referenced with time-motion data to determine classification accuracy. To determine the validity of the measurement of jump height, five participants completed nine jetés, nine sautés and three double tour en l’air from a force plate. The jump height predicted by the accelerometer algorithm was compared to the force plate jump height to determine agreement. Across 1440 jumps observed in time-motion analysis, 1371 true positives, 34 false positives and 69 false negatives were identified by the algorithm, resulting in a sensitivity of 0.98, a precision of 0.95 and a miss rate of 0.05. For all jump types, mean absolute error was 2.6 cm and the repeated measures correlation coefficient was 0.97. Bias was 1.2 cm and 95% limits of agreement were −4.9 to 7.2 cm. The algorithm may be used to manage jump load, implement periodization strategies, or plan return-to-jump pathways for rehabilitating athletes.

Chronic Ankle Instability and Associated Self-Reported Function in South African Professional Ballet Dancers.

Ankle sprains are the most common acute injury among dancers and may result in the development of chronic ankle instability (CAI). Chronic ankle instability is characterized by recurrent ankle sprains, incidents of the ankle "giving way," and sensations of instability and has been reported to negatively impact functioning and psychosocial status. The large number of ankle sprains in addition to contextual factors relating to professional dancing, suggests that CAI may be a significant problem in professional ballet dancers. This study aimed to determine the prevalence of CAI and describe the ankle injury history and level of self-reported function in South African ballet dancers. This descriptive, cross-sectional study included all professional ballet dancers employed by three professional South African ballet companies (n = 65). The Identification of Functional Ankle Instability Questionnaire (IdFAI), Foot and Ankle Ability Measure (FAAM), Dance Functional Outcome Survey (DFOS), and a researcher-developed injury history questionnaire were completed by consenting participants. Descriptive statistics were calculated. A CAI prevalence of 73.3% CI [55.6%, 85.8%] was calculated among 30 participants. Twenty-five (83.3%) participants reported sustaining at least one significant ankle sprain with 88% (n = 22) indicating dance related activities as the cause. Dancers with CAI demonstrated a tendency to have less control over their ankles giving way and tended to take longer to recover from their ankles giving way than those dancers not affected. Eight participants (36.4%) with CAI were identified as having a significant level of disability on the FAAM activities of daily living (ADL) subscale and six participants (27.3%) on the sport subscale. Participants with CAI had a median total score of 83.5; IQR [80 - 90] on the DFOS. The self-reported function of South African professional ballet dancers is not severely affected, however, the high prevalence of CAI and reported symptoms is concerning. Education on CAI symptoms, prevention, and evidence-based management is recommended.

High Rates of Satisfaction and Return to Dance in Current or Former Professional Ballet Dancers After Total Hip Arthroplasty With a Muscle-Sparing Direct Anterior Approach Using Custom Femoral Stems.

Professional ballet dancers have high expectations after total hip arthroplasty (THA), particularly if they intend to resume dancing as performers or teachers. To report clinical outcomes and return to dance after THA with a muscle-sparing direct anterior approach using a custom femoral stem in a cohort of current or former professional ballet dancers. Case series; Level of evidence, 4. Twenty-three patients (26 hips) were included, that identified as current or former professional ballet dancers, from a consecutive series of 1699 hips that underwent primary THA by 1 of 2 surgeons. Both surgeons routinely implanted custom femoral stems using a muscle-sparing direct anterior approach in active and/or high-demand patients. All patients completed a questionnaire postoperatively that assessed dance capabilities, the visual analog scale (VAS) for hip pain (0-10), the VAS for satisfaction with surgery (0-10), the Oxford Hip Score (OHS), and the Forgotten Joint Score (FJS). The initial cohort comprised 19 women and 4 men, with a mean age of 50.5 ± 14.9 years and a mean 38.0 ± 14.4 years of dance experience. One patient underwent revision THA for a leg-length discrepancy, leaving 22 patients (25 hips) with a mean follow-up of 3.4 ± 1.4 years. The mean VAS satisfaction score was 9.8 ± 0.6, and the mean VAS pain score was 0.5 ± 1.0. The postoperative OHS and FJS were 46 ± 2 and 92 ± 15, respectively. Overall, 16 patients resumed ballet at 5.1 ± 3.9 months, 3 resumed other types of dance, and 3 did not resume any type of dance. None of the 6 patients who did not resume ballet indicated pain in the operated hip as the reason for stopping. In current or former professional ballet dancers, THA by a muscle-sparing direct anterior approach using a custom femoral stem yielded excellent clinical outcomes at a minimum of 2 years, with the highest satisfaction score of 10 points reported for 88% of hips and 72% of hips being totally pain free. Furthermore, 73% of patients resumed ballet, and 86% resumed dance in general.

Work-Related Dermatoses of the Feet in Professional Dancers: A Pilot Study

The feet of professional dancers are exposed to high work-related stresses. To date, data from the professional dance sector concerning this matter are lacking. The aim of this exploratory project was to analyze and evaluate skin health in the foot area with regard to the prevalence of dermatoses, their locations, as well as gender-specific and load-specific differences. Professional classical and neo-classical ballet dancers were examined at two time points: in a phase with increased stress (T0: daily training sessions, rehearsals, and high performance frequency) (n=51, 35 females, 16 males) and after a 24-day rest phase (T1: n=35, 28 females, 7 males). In addition, gender-specific and load-specific (T0 and T1) differences were evaluated. All professional dancers were affected by skin lesions of the feet at T0. Hyperkeratosis (96.1%), onychomycosis (27.5%), and subungual hematoma (11.8%) were the most frequent dermatoses of the feet of professional dancers. Onychomycosis affected the nails of the big toes in particular (right 15.7%; left 13.7%), and subungual hematomas were found exclusively on the nails of the first toe (right 7.8%; left 7.8%). Women tended to be more frequently affected by hyperkeratosis, men more frequently by onychomycosis. There were no load-specific differences between the stress and rest phases. The prevalence of work-related dermatoses is equally high among female and male dancers. The results can be used for further research and serve as a basis for specific measures of behavioral and environmental prevention in dance.

Prevalence of Urinary Incontinence and Other Pelvic Floor-Related Symptoms in Female Professional Dancers.

Urinary incontinence (UI) is a common issue in female athletes and is known to negatively impact quality of life and sport performance. However, the prevalence of UI in dancers has not been widely investigated. The purpose of this study was to assess the prevalence of UI as well as other symptoms of pelvic floor dysfunction in female professional dancers. An anonymous online survey that included the International Consultation on Incontinence Questionnaire-Urinary Incontinence Short Form (ICIQ-UI SF) was developed and distributed via e-mail and social media. Two hundred and eight female professional dancers between the ages of 18 and 41 years (mean: 25.4 ± 5.2 years) who had a typical dance training and performance schedule of 25 hours or more per week completed the survey. A total of 34.6% of participants reported experiencing UI, with 31.9% of the dancers who reported UI reporting symptoms consistent with urge UI, 52.8% reporting UI with coughing or sneezing, and 54.2% reporting UI with physical activity or exercise. For those reporting UI, the mean ICIQ-UI SF score was 5.4 ± 2.5 points and the mean score for impact on everyday life was 2.9 ± 1.9. A report of pain with sexual activity and intercourse was significantly associated with presence of UI (p = 0.024), but the effect size was not notable (phi = 0.159). The prevalence of UI in female professional dancers is similar to that found in other high-level female athletes. Based on the notable prevalence of UI, health care professionals working with professional dancers should consider regularly screening for UI and other symptoms of pelvic floor dysfunction.

Rehearsal and Performance Volume in Professional Ballet: A Five-Season Cohort Study.

Few studies have published data concerning the longitudinal rehearsal and performance demands experienced by professional ballet dancers. We aimed to describe the rehearsal and performance volumes undertaken across five professional ballet seasons and identify factors associated with inter-dancer and inter-production variation in dance hours. Scheduling data were collected from 123 dancers over five seasons at The Royal Ballet. Linear mixed effects models were used to evaluate differences in: 1. weekly dance hours and seasonal performance counts across sexes, company ranks, and months; and 2. factors associated with the variation in rehearsal hours required to stage different productions. On average across the five seasons, a peak in performance volume was observed in December, whereas rehearsal hours peaked in October and November and between January and April. Differences in weekly dance hours were observed between company ranks (p < 0.001, range in means: 19.1 to 27.5 hours per week). Seasonal performance counts varied across company ranks (p < 0.001), ranging from 28 (95% CI: 22, 35) in principals to 113 (95% CI: 108, 118) in the rank of artist. Rehearsal durations were considerably greater in preparation for newly created ballets compared with existing ballets (77.8 vs. 37.5 hours). Rehearsal durations were also greater in preparation for longer ballets, with each additional minute of running time associated with a 0.43 hour increase in rehearsal duration (p < 0.001). Full-length ballets, however, were consistently the most time-efficient to stage due to their long performance runs compared with shorter ballets (16.2 vs. 7.4 performances). Training principles such as progressive overload and periodization should be implemented in professional ballet companies to manage the high and variable rehearsal and performance loads.