Journal of Dance Medicine & Science最新文献

Dancers need adequate cardiorespiratory fitness (CRF) levels in order to cope with the demands of dance classes and choreographies. Screening and monitoring of CRF is advised. The aim of this systematic review was to provide an overview of tests used to assess CRF in dancers and to examine the measurement properties of these tests. A literature search was performed in three online databases (PubMed, EMBASE, and SPORTDiscus) up until August 16, 2021. Study inclusion criteria were: 1. a CRF test was used; 2. participants were ballet, contemporary or modern, or jazz dancers; and 3. English full-text peer-reviewed article. General study information, participant information, CRF test used, and study outcome were extracted. If available, measurement property data were extracted (i.e., test reliability, validity, responsiveness, and interpretability). Of the 48 articles included in the review, most used a maximal treadmill test (n = 22) or the multistage Dance Specific Aerobic Fitness test (DAFT; n = 11). Out of the 48 included studies, only six examined the measurement properties of CRF tests: Aerobic Power Index (API), Ballet-specific Aerobic Fitness Test (B-DAFT), DAFT, High-Intensity Dance Performance Fitness Test (HIDT), Seifert Assessment of Functional Capactiy for Dancers (SAFD), and the 3-minute step test. Good test-retest reliability was found for the B-DAFT, DAFT, HIDT, and SAFD. Criterion validity was determined for the VO_2peak of the API, the 3-MST, HIDT, and SAFD. For HR_peak, criterion validity was studied for the 3-MST, HIDT, and SAFD. While different CRF tests are being used in descriptive and experimental research within dance populations, the body of research supporting the measurement properties of such tests is very small. As many studies have methodological flaws (e.g., small participant numbers or no statistical analysis for validity or reliability), additional good quality research is required to re-examine and complement current measurement property results of the API, B-DAFT, DAFT, HIDT, SAFD, and 3-MST.

Introduction: 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.

Methods: 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.

Results: 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.

Conclusion: 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.

Hip hop is a popular dance genre practiced worldwide that has gained popularity since the 1970s. Despite this, studies related to the area and its physiological demands are still scarce. The purpose of this study was to report the cardiorespiratory profile of a group of male and female hip hop dancers to determine the zones of intensity of a predefined hip hop party dance sequence. Eight Brazilian professional hip hop dancers, four women and four men, mean age 22 ± 2.3 years, participated in the study. Using a portable gas analyser (Cosmed K5) their cardiorespiratory variables were measured at two different times: first, during a maximal treadmill test and later during a predefined hip hop party dance sequence. Descriptive statistics (mean and standard deviation) were used for calculating the dependent variables: oxygen consumption (VO₂), heart rate (HR), and the intensity zones for the predefined hip hop sequence. Data normality was verified using the Shapiro-Wilk test. The Mann-Whitney U-test was performed to check any sex-related difference (p < 0.01). No statistical difference between male and female dancers was found in the cardiorespiratory profile and responses to the predefined hip hop party dance sequence. On the treadmill, the participants' VO_2peak was 57.3 ± 12.7 ml·kg^-1·min^-1, and HR_max was 190.0 ± 9.1 b·min^-1. The predefined hip hop party dance sequence was mainly (61%) performed in the moderate aerobic zone. However, when the dancers jumped, the intensity of the sequence increased. This information could be used to develop a specific supplementary training protocols for hip hop dancers to improve their physiological fitness parameters and reduce the incidence of injury.

Introduction: 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.

Methods: 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.

Results: 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).

Conclusions: 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.

Introduction: This study investigated how toe flexor muscles are related to postural stability in 11 ballet dancers and 12 non-dancers.
Methods: Toe flexor strength (TFS), cross-sectional areas (CSA) of the abductor hallucis, flexor hallucis brevis, flexor digitorum brevis, flexor hallucis longus (FHL), and flexor digitorum longus, and center of pressure (COP) displacement during single-leg demi-pointe were measured. Correlations between toe flexor strength and COP displacement and between CSA and COP displacement within each group were calculated using Pearson's correlation coefficient or Spearman's correlation coefficient.
Results: The dancers showed smaller COP displacement than the non-dancers (p < 0.05). Toe flexor strength in dancers was moderately negatively correlated with COP displacement in the anterior-pos- terior direction (r = -0.54, p < 0.01) and total COP displacement (r = -0.57, p < 0.01). Only the CSA of the FHL in dancers exhibited a significant negative correlation with COP displacement in the anterior-posterior direction (r = -0.42, p < 0.05) and total COP displacement (r = -0.52, p < 0.01).
Conclusion: The present study found a relationship between the toe flexor strength and COP displacement and CSA of toe flexor muscles and COP displacement during one-legged demi-pointe standing. These results suggest that the development of the toe flexor muscles may be involved in the balance control of dancers.

This study aimed to investigate the perceptions of training load practices of dance artistic and health professionals. Artistic staff and health professionals with experience in dance were invited to participate in a cross-sectional survey study relating to training load practices in pre-professional and professional, ballet and contemporary dance. The survey was developed from previous investigations in soccer and consisted of multiple-choice, Likert scale, and free-text responses. Responses to closed questions were reported by percentage and 95% confidence intervals (95% CI). Thematic analysis was performed by two independent assessors of free-text responses. There were six artistic staff and 18 health professional participants. Artistic staff were perceived to be "mostly/completely responsible" for planning training (artistic staff: 100%, 95% CI: 61%, 100%; health professionals: 94%, 95% CI: 76%, 100%), with health professionals "mostly/completely responsible" at times of injury (artistic staff: 83%, 95% CI: 41%, 99%; health professionals: 95% CI: 61%, 96%). Both groups reported using individual modification to manage training loads and recognized the benefits of rest. Artistic staff recognized the need to modify training when injured, in line with experience levels, workload, age, and general health. Both groups "agree/strongly agree" that monitoring would be or is useful (artistic staff: 83%, 95% CI: 41%, 99%; health professionals: 95% CI: 61%, 96%). This investigation provides insight into the perceptions of artistic staff and health professionals with experience in dance toward training practices. Artistic staff and health professionals need to work together and adapt monitoring practices to their context to support artistic staff in planning training. The findings guide the implementation of these interventions by understanding potential barriers to their effectiveness that may potentially reduce injury.

Objectives: Performance anxiety (PA) is debilitating and impacts the sufferer's ability to perform. Forgetfulness, concentration loss, and physical symptoms develop, leading to some giving up performing.
Methods: An online questionnaire was used to gather data, including demographic questions and the Kenny Music Performance Anxiety Inventory (K-MPAI). The questionnaire was distributed via social media and the British Association for Performing Arts Medicine (BAPAM) database. Data was collected over a 2-month period and was analyzed using simple proportions with a score of ≥ 104 on the K-MPAI indicating the presence of PA and ≥ 130 indicating notable levels of PA.
Results: Thirty-three participants completed the questionnaire (57.6% female). When looking at the ages of participants (18 to 80), the most common age range was 31 to 35 (33%). Two-thirds of participants were deemed to suffer from PA after completing the K-MPAI. A large proportion of participants with PA (63.6%) scored above the threshold score of 130 indicating "significant performance anxiety." Females or currently unemployed performers showed higher levels of PA than other subgroups. However, a chi-squared test showed no significance between sexes (p = 0.32) or employment status (p = 0.31) and the incidence of PA.
Conclusion: The research showed that PA is a significant issue in musical theater, as it is with other musicians who have been studied extensively. We conclude that more research is needed to look at appropriate treatments specifically for musical theater performers.

Introduction: As the world population ages, practitioners use community-engaged interventions to help older adults stay healthy. Engaging in arts programs (e.g., dance or music) reportedly improves physical and mental health, but little research exists examining these effects in community-dwelling older adults. Our purposes were to examine how taking part in 10-week, twice per week community arts programs (dance and music) and control (social conversation) affected physical and mental health in community-dwelling older adults and their perceptions after program participation.
Methods: In this randomized controlled trial, 64 older adults over 65 years of age (71.3 ± 4.6 years, 166.9 ± 8.3 cm, 78.1 ± 18.1 kg) took part in community-engaged arts programs: ballroom dance (n = 23), music (ukulele-playing, n = 17), or control (social conversation n = 24), two times per week for 10 weeks. Participants' physical health using the Short Physical Performance Battery (SPPB; score 0 = worst to 12 = best) and mental health using the Montreal Cognitive Assessment (MoCA; score = 0 to 30, where less than 26 = normal) were tested three times: 1. before (pre), 2. at the end of 10 weeks (post-1), and 3. 1 month after intervention (post-2). Separate 3 (group) x 3 (time) ANOVAs and adjusted Bonferroni pairwise comparisons as appropriate examined changes across groups and time. Focus group interviews and surveys were audio recorded, transcribed, and analyzed using inductive thematic analyses to examine participants' perceptions.
Results: Across all groups, participants had an 87.8% attendance and an 87.5% retention rate. Participants' SPPB performance improved over time (pre = 10.5 ± 1.4, post-1 = 10.7 ± 1.3, post-2 = 11.3 ± 1.0; p < 0.001), but similarly across groups (p = 0.40). Post-hoc analyses revealed that performance improved from pre to post-1 (p = 0.002) and pre to post-2 (p < 0.001). Participants' cognition improved over time (pre = 26.3 ± 2.8, post-1 = 27.3 ± 2.6, post-2 = 27.5 ± 2.5, p < 0.001), and similarly across groups (p = 0.60). Post-hoc analyses revealed that cognition improved from pre- to post-1 (p = 0.002), and pre- to post-2 (p = 0.001). Participants consistently mentioned increased social engagement as the major reason for participation.
Conclusions: Overall, taking part in community-engaged arts (dance and music) and social conversation programs positively influenced physical and mental health in older adults. Still, as all groups improved equally, the results may partly be due to participants having normal physical and mental function pre-participation and due to them learning the test over time. These study findings imply that providing fun and free community-engaged programs that empower participants to be more engaged can positively influence physical and mental health and promote successful aging in older adults.

Neuromuscular warm-up exercises (NMWU) have been shown to prevent injuries. In dance, research on warming-up is scarce. We investigated warm-up habits among ballet dancers and the effects of NMWU and traditional ballet-specific warm-up (TBSWU) on injuries. Using a cross-sectional survey among ballet dancers over the age of 18 years, we recorded acute and overuse injuries sustained in the previous 2 years. Warm-up behavior was assessed through 28 items. Dancers were grouped into NMWU or TBSWU: NMWU was based on neuromuscular warm-up programs in sports science and included exercises improving strength, power, proprioception, sensorimotor control, or cardiovascular stimulus; and TBSWU consisted of stretching, dance-technical exercises, marking steps and running-through-choreographies, or stretching with tools. Separate linear regression analyses adjusted for confounding factors were performed for acute and overuse injuries. A total of 192 dancers (26.7 ± 7.82 years, 159 females, 132 professionals) reported 203 acute and 469 overuse injuries. In total, 47.4% of dancers always warmed up (mean duration 20.7 ± 13.2 minutes) based on stretching (63%), technical-exercises (58.9%), strength-training (54.7%), and the barre (53.6%); and 9.4% never warmed up. A total of 31 dancers (16.15%) were classified as TBSWU, 16 dancers (8.3%) for NMWU, and 145 dancers did combined exercises. Those in the NMWU group were associated with fewer overuse injuries compared to those in the TBSWU group (β = -2.34; 95%CI -3.54 to -1.14). No association was found with acute injuries. As in other athletes, NMWU might be protective against overuse injuries in dancers. Large-scale prospective cohort studies are needed to gain more insight into NMWU as a possible component of injury prevention in ballet.

Dancing en pointe is an integral aspect of ballet for female dancers and they start pointe training in young adolescence. The primary objective of this review was to investigate the screening tests used to determine pointe readiness in young adolescent female dancers, and the secondary objective was to determine the injuries associated with pointe training. The search engines Google Scholar, PubMed, Scopus, and Web of Science were mined using medical subject heading terms "pointe," "pointe readiness," "injury," "young," "adolescent," "female," and "dancer," and a manual search of relevant articles was conducted. The inclusion criteria were: females aged 8 to 20 years, pre-pointe, training en pointe, and pointe-related injury. The search strategy followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The following data were extracted; first author, year of publication, study design, participant size, mean age, testing, outcome, and general notes of each study. Risk of bias was evaluated using the Research Triangle Institute Item Bank (RTI-IB). Eight cross-sectional studies met the inclusion criteria. Results suggested that the topple, airplane, sauté, and relevé tests are statistically better determinants of pointe readiness than chronological age alone. Utilizing these methods alongside age, strength, body maturation, range of motion (ROM), and teacher evaluation could provide an all-round insight into a dancer's readiness for pointe. However, the included studies had contradictory outcomes with regard to pointe-related injury and the review's conclusions are limited by methodological design.