Journal of Dance Medicine & Science最新文献

Introduction: Transiting to dancing en pointe is an important milestone for young dancers who wish to progress in ballet training. Various criteria exist regarding pointe readiness, including age, range-of-motion, endurance, strength, balance, and technique. However, awareness and use of these criteria by dance instructors is currently unknown. The purpose of this pilot study was to assess the awareness and use of pointe readiness criteria by youth ballet instructors. Methods: A cross-sectional web-based survey study design was used, which included questions regarding dance instruction experience, dance studio characteristics, and criteria used to assess pointe readiness. Ballet instructors were recruited for participation. Data are presented as percentages and frequencies. Results: Thirty-one ballet instructors completed the survey from 15 states (1 international). Years of pointe ballet instruction ranged from 2 to 30+ years, with 35% indicating more than 30 years of experience. Instructors reported students begin pointe at age 11.8 years (range 9-15 years). A majority of instructors require 5 years of ballet experience prior to dancing en pointe (range 2-8 years). Reported pointe readiness criteria included strength (100%), dance technique (94%), age (87%), and years of ballet experience (71%). While all instructors reported evaluating a dancer's strength, assessments of flexibility and movement quality were not evaluated by 42% and 45% of instructors, respectively. Strength, dance technique, and age were rated as the greatest indicators of a dancer's readiness to begin pointe. Finally, instructors reported low knowledge of existing pointe readiness criteria. Conclusion: Ballet instructors initiated pointe work at age 12 and required 5 years of ballet experience before beginning to dance en pointe. While strength, dance technique, and age were the top considerations for evaluating readiness, approximately 40% of instructors did not evaluate flexibility or movement quality prior to progressing to pointe, and overall, knowledge of existing criteria was low.

Introduction: Ballroom dance participation is growing due to its competitive, social, and health benefits. Despite its popularity, there is limited information regarding the biomechanics of ballroom dance. This study aimed to quantify the vertical ground reaction force and its loading rate during two common rhythm ballroom dance steps, and to determine the variance of these variables across three levels of ballroom dancers. Methods: Fifty-six participants (20 inexperienced, 18 recreational, and 18 professional) performed nine common American rhythm ballroom dance elements from the American Rumba box step and the foundational step of the Cha Cha Cha on a vinyl dance floor over two embedded force plates. The Kruskal-Wallis test with experience level as the independent variable was used to compare variables among dance levels. Levene's test for equal variances was used to determine if the variance among the dance levels differed. Results: Results indicated that both the vertical ground reaction force and the rate of loading are associated with the dancing experience level for eight of the nine dance elements (P-values ranging between <0.001 and 0.040 for the ground reaction force and between <0.001 and 0.001 for the rate of loading). Forces were highest in the inexperienced level and lowest in the professional level. This finding was pronounced when stepping backward and leftward. Additionally, the variance in the force-related measurements was smaller among more experienced groups than their less-experienced counterparts. Conclusion: These findings provide an initial understanding of the kinetics underlying the movement patterns of foundational rhythm ballroom dance. This study is a starting point for future research to better understand other ballroom dance patterns and explore the mechanisms of ballroom dance-related musculoskeletal injuries.

Introduction: Scientific peer-reviewed journals are crucial for disseminating scholarly information. Bibliometrics, the application of statistical methods to analyze academic literature, offers a quantitative approach to evaluate research output, assess quality, and examine patterns in publication, authorship, and thematic trends. This study employed bibliometric analysis to comprehensively examine the landscape of Dance Medicine and Science (DMS) research, including its quality, demographic characteristics, and thematic evolution. This study aimed to fill this gap by analyzing the dissemination of DMS research output between 2007 and 2024 using bibliometric indicators. We sought to answer key questions about the field's annual scientific production, publication venues, journal comparisons, geographical distribution of authors, cross-institutional and international collaborations, gender parity in authorship, and thematic trends in current DMS research. Methods: Using the Core Collection of Clarivate Analytics' Web of Science©, we filtered articles using dance-related search terms: "dance," "science," "medicine," and "education." From this search, we extracted 2750 peer-reviewed articles to construct our analyses. We utilized visualization of similarity (VOS) software as well as descriptive statistics to tabularize, visualize, and explore bibliometric maps of science and medical articles related to dance. Results: The Journal of Dance Medicine & Science (JDMS) led in quantity of publications with over 304 articles in the seventeen-year period. Most DMS research is produced by authors in North America, Europe, and Australia, primarily examining Western dance styles. We observed a higher proportion of feminine names among first authors in DMS research, though further analysis is needed to understand overall gender distribution across all author positions. The field showed an annual growth rate average of 11.04% in publications. Our network analysis revealed distinct clusters of research themes, highlighting the multidisciplinary nature of DMS. Conclusions: Our analysis revealed significant growth in DMS research over the studied period. The Journal of Dance Medicine & Science emerged as the leading publication venue. Geographically, we found a concentration of research output from North America, Europe, and Australia, highlighting potential areas for expanding international collaboration. Gender distribution among authors was nearly balanced, with a slight majority of female first authors. Thematic analysis identified three primary research clusters: injury prevention, performance enhancement, and dance education, providing insight into the field's current focus areas. These findings offer a comprehensive overview of the DMS field, illustrating its evolution, key contributors, and emerging research themes, while also identifying areas for future development and collaboration.

Introduction: Amongst dance programs, mitigating the risk of injury using comprehensive screening tests is essential. Currently, the lack of standardization for tests/measurements in screening methodology poses as the main barrier to building more effective, future screening programs for dancers. Our objective is to fill critical gaps in the existing literature on dancer screening by producing normative data, describing screening outcome changes amongst a dancer's college career, and providing guidance to building similar screening programs. Methods: This original quantitative study establishes normative data found in six tests (the Functional Movement Screen (FMS), Beighton Scale, Harvard Step Test, Y-Balance Test, Sagittal & Frontal Plane Core Stability (Plank Testing), and Turnout Test) within the DanceFIT Injury Prevention Screen collected from Dance Performance and Choreography-major students at a university over the course of ten years. Exploratory data analysis, including Cronbach's alpha, principal components analysis (PCA), and parallel analysis, and correlation calculations were completed. Results: For all main outcomes of the screening tests, except Plank Testing, the percent change of means increased the most between 1st and 2nd year students (ie, students demonstrated the greatest improvement during this period). The overall screen test's alpha value, .87 (95% CI, 0.86-0.89), fell in the acceptable alpha values range. PCA, parallel analysis, and eigenvalues demonstrated how four to seven components explained the variance of the screening tests. The Turnout components are highly correlated, the Plank Testing components moderately correlated, and the Harvard Step Test and FMS components were lowly correlated. Conclusion: The screening test data indicate replicability for future dancing injury prevention screening programs. Findings from this study suggest increasing the current literature's 14-point cutoff of FMS testing in dancers, adjusting components of screening tests, and adapting courses based on screening test performance to reduce injury risk for dancers. Next steps include prospective studies to track injuries, validate screening methods, and establish appropriate cut off scores for dancers.

Introduction: Ballet dancing is driven by goals of artistic performance that depend on aesthetic standards. These standards involve maintaining a slim and muscular physique. Therefore, dancers tend to adopt eating behaviors that may have long-term consequences for their health and performance. This study aims to explore ballet dancers' perceptions of their dietary behaviors. Method: This study employed a qualitative approach, utilizing semi-structured interviews conducted via videoconference. Recruitment was carried out on social media in January 2023. Interviews were analyzed through reflexive thematic analysis. Each interview was coded using an inductive approach. Categories were grouped into sub-themes and themes. Participant citations were then translated. Results: Eleven interviews were conducted with professional ballerina dancers from various Operas in France and Monaco. Analysis generated three themes. Firstly, dancers must meet specific ballet standards instilled in them by both instructors and peers. Dance instructors were perceived as authority figures, and their words about their students' physical appearance during puberty often carried stressful memories. Secondly, our participants discussed their relationship to food. To match the ideal ballerina's appearance, dancers recounted adopting unhealthy eating behaviors. Thirdly, once in a ballet company, dancers recalled gaining maturity and knowledge, which helped them realize the consequences of these negative behaviors. They became more concerned about their health and adapted their diets. Individual characteristics, personal reactions to instructors' demands, and the influence of significant others influenced their eating behaviors. Our participants voiced a desire for attitudes to change regarding ballet standards. They wished for more medical follow-up concerning physical and mental health. Conclusion: When it comes to diet, professional ballet dancers should be considered not just as artists, but also as elite athletes. Eating behaviors play a fundamental role in an athlete's performance and well-being, as they help meet nutritional needs in the context of high athletic fueling demands.

Introduction: Turnout, or external rotation, is a fundamental movement pattern in dance and has been associated with injury risk. While previous research has examined the relationship between turnout and range of motion (ROM) while other contributing factors such as strength and movement competency have been largely overlooked. This study aimed to explore the relationships between functional turnout measurements and movement competency screen (MCS) scores, passive hip external rotation (PER) and external rotation strength in collegiate dancers. Understanding these relationships is crucial for optimizing training and reducing injury risk in dancers. Methods: Twenty-one undergraduate dance majors participated in a cross-sectional study assessing PER, strength, movement competency (MCS) and turnout in a single session. Turnout was assessed statically (Static Functional Turnout, SFT) and dynamically (Dynamic Functional Turnout, DFT), in both first and fifth positions. Data were analyzed using IBM SPSS Statistics v27.0.1.0, with Pearson correlations used to examine the relationships between variables. Results: No statistically significant relationships were found between individual turnout measurements and MCS scores. Most participants (n = 18) exhibited greater SFT than their available PER, suggesting that turnout was achieved through movement at joints other than the hips. These dancers had lower PER and hip external rotation strength compared to those whose SFT was less than their PER. The extent to which dancers exceeded their PER during SFT had a moderate to good negative correlation with MCS scores (R = -.555, P = .017). This suggests that dancers who generate turnout beyond their passive hip mobility have lower movement competency. Conclusion: Turnout execution in dancers varies widely and does not consistently correlate with hip external rotation strength, ROM, or movement competency scores. However, dancers who exceed their available PER during the SFT demonstrate lower movement competency, suggesting that motor control may be an important factor in turnout execution.

Introduction: There are similarities in physical and psychological demands, but differences in working conditions between professional freelance and company dancers. The purpose of this study is to examine the work ability of professional dancers working in both of these fields and to analyze influencing factors associated with each work model.

Methods: A partially standardized survey was used to collect sociodemographic and dance-specific data. Work Ability Index (WAI) scores were also collected. The sample consisted of 247 participants (172 freelance and 75 company dancers). Differences between the subgroups were analyzed using Analyses of Variance (ANOVA), parametric and non-parametric tests. Factors impacting the WAI score(s) were determined by the employment of several generalized linear regression models.

Results: The sample shows moderate to good work ability, and statistical analysis revealed no significant difference between professional freelance and company dancers (P = .984). There are significant differences between the subgroups of professional dancers in terms of age (P < .01), ethnicity (P < .001), predominant dance style (P < .001), weekly training hours (P < .001), number of workplaces (P < .001), and distribution of work content (P < .001). Regression shows that negative factors for WAI are female (RF = -2.438, P < .1) and non-binary gender (RF = -7.822, P < .5) and increasing number of workplaces (RF = -1.125, P < .05). Positive factors include work in commercial (RF = 6.399, P < .01) and jazz dance (RF = 6.503, P < .01).

Conclusions: Professional freelance and company dancers generally demonstrate moderate to good work ability, which indicates that there is room to increase the proportion of those with very good work ability. Given that ability to work is influenced by multiple factors, special attention should be given to female and non-binary dancers, who are more likely to experience negative impacts on their work ability.

Objectives: Lower back pain (LBP) is a common issue among dancers across various styles. This study aims to investigate the 12-month prevalence, level of disability, duration and frequency of LBP episodes in a sample of dancers engaged in different dance styles. Additionally, it seeks to identify risk factors for low back pain, including dance style, sociodemographic factors, and psychosocial factors.

Methods: A survey was conducted via an online questionnaire utilizing www.SoSciSurvey.de. 77 dancers aged between 14 and 45 years, who danced at least 1 hour per week on average, were included. The sample comprised both recreational and professional dancers, exhibiting a wide range of workloads. Participants conveyed their sociodemographic Information, parameters related to their dancing and their 12-month prevalence of LBP including the duration and frequency of LBP episodes. To assess the degree of LBP induced disability, participants completed the Oswestry disability Index (ODI). A Chi-squared Test (Prevalence), Kruskal-Wallis Test (H-test), and Spearman correlation (confounders) were conducted.

Results: The 12-month prevalence of LBP in the cohort was high with 83.1%. The dance style did not have a statistically significant impact on the 12-month prevalence (P = .844) and the ODI (P = .065). Satisfaction with their own dance performance, coaching staff and the dance group, as well as heavy manual labor, smoking and psychological comorbidities were all statistically significantly correlated with at least 1 of the outcomes (P < .05).

Conclusion: Psychosocial factors, psychological comorbidities, and lifestyle factors such as occupation and smoking status impacted LBP. Dance style did not affect LBP significantly.

Aim: This study investigated how muscle activation and movement altered as a result of dorsiflexor and plantarflexor muscle fatigue in dancers during single-leg relevés.

Methods: 14 participants with current or recent experience in dance performed 10 single-leg relevés before and after a fatigue protocol at a set tempo of 46 beats per minute. The pre-fatigue and post-fatigue differences were assessed via surface electromyography of the lateral gastrocnemius, medial gastrocnemius, soleus, and tibialis anterior during the ascending and descending phases. Kinematic data was obtained and assessed using 3D motion capture technology.

Results: No significant differences in muscle activation occurred from pre-fatigue to post-fatigue during the ascending phase. However, there was a significant increase in activation during the descending phase in both the soleus (P = .020) and lateral gastrocnemius (P = .028). Additionally, there was a significant decrease in ankle range of motion (P = .004) and heel height achieved (P = .006) from pre-fatigue to post-fatigue. There was also a significant decrease in ankle dorsiflexion (P < .001) and plantarflexion (P = .014) post-fatigue.

Conclusion: Overall, ankle plantarflexor fatigue results in an inability to maintain movement despite increased muscle activation. Future research could support in validating the findings that dancers should limit working past or near fatigue, as it could lead to increased mechanical compensations which increase the risk of injury.

Introduction: Excessive contact forces on the hands during breaking can potentially cause a high injury incidence. Chair freeze is a basic posture unique to breaking; however, its effect on the hands remains unclear. Clarifying dancer-specific factors is essential for preventing trauma and overuse injuries. This study aimed to investigate the contact load and pressure on the hands during chair freeze and their determinants.

Methods: 15 professional breakers were recruited. The peak landed load per bodyweight and contact pressure were measured using thin-film pressure sensors in the chair freeze and handstand postures. The location of the highest pressure was also assessed. The following possible factors of load and pressure were assessed: age, height, weight, body mass index, hand axis, practice duration, and grip strength.

Results: Load per bodyweight and pressure were significantly higher in the chair freeze than in the handstand (0.69 bodyweight vs 0.47 bodyweight and 247.1 kPa vs 155.8 kPa; P < .0001 and P < .0001, respectively). In 14 of 15 dancers (93.3%), the highest pressure was concentrated on the radial side of the palm during chair freeze. Body height and weight were significantly correlated with load per bodyweight and pressure in chair freeze (ρ = 0.55, 0.57, 0.54, and 0.59; P = .036, .028, .038, and .020, respectively).

Conclusion: Load per bodyweight and pressure on the landed hand was 1.5- to 1.6-fold higher during the chair freeze than during the handstand, concentrating on the radial side of the palm. Dancers' body size was associated with the contact force on the hand in the chair freeze.