Journal of Dance Medicine & Science最新文献

Introduction: The purpose of the study was to examine if dance-specific aerobic fitness test (DAFT) heart rate variables were associated to lower-extremity injuries in contemporary dance students.

Methods: A total of 235 first-year contemporary dance students (18.6 ± 1.2 years) were prospectively followed over the first 4 months of their academic year. Peak heart rate (HR_peak) in the final stage of the DAFT and heart rate recovery (HRR) 1 minute after DAFT completion were measured. Lower-extremity injuries were registered using a self-reported monthly questionnaire including the Oslo Sports Trauma Research Centre Questionnaire on Health Problems (OSTRC-H). Three injury definitions were used (all-complaint injury, substantial injury, and time-loss injury). Associations between DAFT HR_peak, HRR and lower-extremity injury prevalence and severity were examined with regression analyses.

Results: Lower-extremity injury prevalence was 36.2% (n = 85), 13.6% (n = 32), and 22.6% (n = 53) for all-complaint, substantial and time-loss injuries, respectively. There were no significant associations between HR_peak or HRR and injury prevalence using either of the 3 injury definitions. There were no significant associations between DAFT HR_peak or HRR and injury severity (days off due to injury or OSTRC-H severity score). Multivariate analyses showed significant associations between age and substantial injuries (OR 1.807; 95% CI 1.242-2.630; P < .01) and between age and time-loss injuries (OR 1.441; 95% CI 1.074-1.933; P < .05).

Conclusion: Aerobic fitness measured with the DAFT was not associated with lower-extremity injury risk or injury severity. Higher age was associated with substantial and time-loss lower-extremity injuries.

Background: Dance is a popular activity worldwide that comes with inherently high injury rates. Despite the call for implementation and evaluation of injury prevention strategies, the utility and efficacy of injury prevention practices in dance are unknown. Objective: The primary objective of this systematic review was to describe dance-specific injury prevention strategies in any dance population. The secondary objective was to evaluate the effectiveness of these strategies in the reduction of injury prevalence or incidence rates. Methods: Six electronic databases were searched to March 2024 (Medline, EMBASE, SportDiscus, CINAHL, SCOPUS, Cochrane). Selected studies met a priori inclusion criteria that required original data describing an injury prevention strategy for any genre of dance. Studies were excluded if; no injury outcomes were reported, no injury prevention strategy was utilized, or if dance was used as a therapeutic intervention/fitness. Two reviewers independently assessed abstracts and full texts for inclusion. Study quality was evaluated using the Joanna Briggs Institute Level of Evidence tool. Results: From 2209 potentially relevant records, 8 studies met criteria for inclusion. Injury prevention strategies were diverse across conditioning and exercise programs, neuromuscular training warm-up, psychological coping skills training, and educational programs, with a range of duration and adherence measures. Due to inconsistent injury surveillance methodology, efficacy of these programs could not be determined. Quality of included studies was moderate to high, with moderate to low risk of bias. Conclusions: Efficacy and adherence to dance-specific injury prevention strategies are understudied in the dance science literature. Conditioning and exercise programs are currently the most common injury prevention strategies, with initial evidence suggesting they may be efficacious in reducing injury rates. Further research using valid injury surveillance methodologies and standardized injury definitions to examine the efficacy of these strategies in reducing dance-related injury is needed. Level of evidence: I.

Background: It is already known that the prevalence of ankle sprain is high in dancers, leading to chronic ankle instability (CAI) and, consequently, affecting jump landing. Therefore, methods that allow the early identification of jump landing alterations related to CAI are necessary. Research Question: This study aimed to investigate if regional plantar force estimated from plantar pressure distribution is different between dancers with and without ankle instability during jump landing. Methods: Female dancers with (n = 12) and without (n = 14) CAI performed single-leg jumps on a force plate (FP), with the insole of a dynamic plantar pressure system inside the ballet shoe. Peak vertical ground reaction force (measured by FP) and peak plantar force of 8 different foot regions (estimated by plantar pressure distribution) were compared between the groups in the first 200 ms after landing, using the t-test and 2-way ANOVA, respectively. Results: No differences were found between the groups considering the peak vertical ground reaction force. There was a higher plantar force on the lateral hindfoot in the group with CAI. Significance: Considering that the higher plantar force on the lateral hindfoot is in accordance with the greater inversion found in people with ankle instability and during sprains, insole dynamic plantar pressure systems were able to identify differences in the jump landing of dancers with and without ankle instability and could be used to early identify risky landing patterns, as well as in real-time feedback during treatment or preventive exercise programs.

Background: Bhangra dance is vibrant and energy demanding art form involving dynamic footwork, jumps, kicks and rapid movements. Poor biomechanics and uneven plantar pressure is a crucial factor for injury among dancers thus, this study protocol aimed at evaluating the efficacy of comprehensive foot strengthening program in improving faulty foot biomechanics and plantar pressure distribution to reduce the risk of lower limb injuries among male Bhangra dancers.

Methods: A single-blinded randomized controlled trial (RCT) will be performed. One hundred forty professional dancers will be recruited for this study based on G* power calculations. Seventy participants will be randomly allocated to the experimental group, undergoing a structured intrinsic foot strengthening program (IFSP; 12 weeks, 5 days/week, 30-60 minutes, mild-severe intensity). Seventy participants will be allocated to the waitlist control group, which will follow their exercise regime and dance training (randomization 1:1 ratio). Outcome measures to assess biomechanical characteristics of the foot and plantar pressure distribution will be foot posture index, navicular drop test, feiss line, arch height index, foot print parameters (Clark's Angle, Chippaux-Smirak Index, Staheli Index), and baropodometer at baseline (0 week), and at the end of the exercise program (after 12th week). Injury incidence and type will also be recorded using a self-designed questionnaire.

Discussion: This study aims at evaluating the efficacy of comprehensive foot strengthening program in improving foot biomechanics and plantar pressure distribution to reduce the risk of lower limb injuries among male Bhangra dancers. The findings of this RCT will have implications for dance training protocols and injury prevention strategies.

Trial status: Recruitment has not yet started.

Objective: To analyze the effects of 12 weeks of free dancing compared to the control group and the reference group without breast cancer, on depressive symptoms, anxiety and stress in women after breast cancer surgery and to verify the association between the variables. Methods: Randomized clinical trial, comprising women after breast cancer surgery (57.7 ± 9.0 years) and women without breast cancer (51.5 ± 10.8 years), divided into 3 groups; (a) received the free dance intervention (n = 11); (b) control group with breast cancer (n = 11) maintained their routine activities, and (c) control group without breast cancer (n = 12) who were matched by age and could not perform physical exercise during the study period. The dance intervention lasted 12 weeks, with 60-minute sessions, held twice a week. The evaluated outcomes were: depressive symptoms (Beck Depression Inventory), anxiety (Beck Anxiety Inventory), and stress (Perceived Stress Scale). Results: There was statistically significant improvement in the intragroup for free dance in depressive symptoms (P = .025), anxiety (P = .009) and stress (P = .050). No significant intragroup differences were found in the control group I and control group II, as well as intergroup differences. In the association of variables, the healthy reference group worsened in the simple analysis, for anxiety (P ≤ .001) and stress (P = .040), and worsened in the adjusted analysis, also for anxiety (P ≤ .001) and stress (P = .025). Conclusion: Free dancing had positive effects on depressive symptoms, anxiety and stress in women after breast cancer surgery. After verifying the association of the variables, it was noticed a worsening of the variables in the CGII. Clinical registry: Brazilian Registry of Clinical Trials (ReBEC) (no. 0RBR-772ktp).

Introduction: There is a dearth of dance-related injury epidemiology within the breaking competition setting. Breaking injury surveillance data has predominantly been collected retrospectively at healthcare facilities or through survey research. Methods: Medical staff were available at 6 breaking competitions between 2021 and 2023 to provide musculoskeletal care and triage. In addition to consent of treatment, participants provided their age, gender, and injured body area(s), symptom onset, and description. A total of 157 patient reports were obtained, de-identified, and utilized for comparative frequency and logistic regression analysis. Results: The most common body areas that breakers sought care for were: 39% (n = 61) shoulder, 32% (n = 51) neck, 32% (n = 50) lower back, and 25% (n = 40) upper back. The majority of injuries 61% (n = 95) occurred >3 months prior to competition. The most common descriptions of injury were: 57% (n = 89) tightness, 46% (n = 73) pain, and 33% (n = 52) soreness. Logistic regression analysis revealed that: older patients have higher odds of experiencing the issue during or before the competition (P-value = .003); and that age was the only variable that was borderline statistically significant for hip injury (P-value = .055). Conclusion: The highest frequency of dance-related injury within a breaking competition setting cohort was found to be in the shoulder, neck, and back. The highest frequency of injury description were tightness, pain, and soreness. There was a large frequency of chronic injuries that were seen, and older patients were found to have a higher odds of experiencing and seeking medical treatment for a chronic injury. Access to injury management services and education for the shoulder, neck, and back should be provided at breaking competitions to improve health outcomes. Level of Evidence: Level 4.

Introduction: Knee-drop landings following a dance leap are often used in contemporary dance choreography, but there is limited research into the biomechanical demands of these types of landing. This study aimed to investigate the effects of a verbal cueing intervention on the performance and kinetics of a common knee-drop landing in contemporary trained dance students. Method: Pre-vocational dance students participated in this study (n = 8). A quasi-experimental research design was followed to collect kinematic and kinetic data using 3D motion capture and force plates following the take-off and during a knee-drop landing of a contemporary dance style leap pre and post a verbal cueing intervention. Performance variables analysed were jump height and flight time, while kinetic variables included vertical ground reaction forces (vGRFs) and loading rates. Results: A statistically significant increase in jump height and flight time was found post intervention; There was no significant difference between pre and post intervention for peak vGRFs at foot or knee impact or loading rate of the whole landing phase. Conclusion: The verbal cueing intervention was successful in increasing flight time and jump height, indicating optimised performance. The lack of significant difference in peak vGRFs and loading rate in the landing phase implies that the intervention did not have a detrimental effect on musculoskeletal loading. These findings demonstrate the positive influence of a verbal cue which focusses on increasing flight time and opposing the landing for enhancing the execution of a dance leap without negatively affecting the forces being experienced in the knee-drop landing that followed. However, it should be noted that the small sample size and lack of a control group in this study may limit the reliability of findings and mean that the generalizability of these findings should interpreted with caution.

Purpose: This longitudinal study aimed to monitor changes in heart rate (HR) variables during the dance-specific aerobic fitness test (DAFT) in contemporary dance and dance teacher students across their first, second, and third academic year. A secondary objective was to examine the influence of sex (female/male) and educational program (dance or dance teacher) on these changes. Methods: Between 2016 and 2024, a total of 408 students from a contemporary dance or dance teacher program completed the DAFT twice per year across their first, second, and third year of study. Peak heart rate (HR_peak) was determined at the end of the DAFT and heart rate recovery (HRR) was determined after 1 minute of rest. Repeated measures ANOVAs were used to assess within-subject changes in HR_peak and HRR over time. Between-subjects main effects of sex and educational program were analyzed, along with interactions between time and these factors. Results: The repeated measures ANOVA showed a significant effect of time for HR_peak (P < .001, ŋ_p² = 0.293). Pairwise comparisons showed that each subsequent measurement of HR_peak was significantly different from the first 2 measurements (September and February, year 1). HR_peak was significantly higher for females than for males at all 6 measurements (P = .003, ŋ_p² = 0.234). A significant interaction effect between time and educational program (P = .023, ŋ_p² = 0.085) was found. There was no significant effect of time for HRR (P = .159). Conclusion: HR_peak at the end of the DAFT test decreased over the course of 3 academic years. This decrease was more pronounced in dance students compared to dance teacher students, indicating that training intensity and curriculum structure influence aerobic adaptations. HRR remained stable over time, suggesting that additional targeted training may be needed to increase recovery capacity when required.

Introduction: Unlike sports, where performance is measured quantitatively, ballet performance is assessed by viewers depending on their aesthetic perspective of view. Previous research on pirouettes has primarily examined biomechanical parameters, such as comparing ground reaction forces and rotational axis across different skill levels, as well as investigating angular momentum and spotting techniques in relation to the number of turns. However, it remains unclear whether these biomechanical indicators correspond to dancers' perception of beauty during rotation movements, as their perception of aesthetically competent performance and their body consciousness during rotation remain unknown. Exploring both dancers' and teachers' perspectives on how they evaluate aesthetics and on which body regions they consciously focus to refine their movements may reveal key elements of aesthetically competent performance, thereby contributing to a deeper understanding of aesthetic movement in ballet. In this study, "perception of beauty" refers to the overall impression of aesthetic quality as judged by observers, whereas "body consciousness" denotes the specific body parts that dancers themselves attend to when executing movements. Here, we aimed to investigate the elements of the aesthetically competent pirouette from the dancer's aesthetic perception and explore their body consciousness. Methods: In an online questionnaire survey, 108 dancers answered the following questions regarding pirouette en dehors and en dedans; (1) definition of the beautiful pirouette, (2) attention during turn, (3) attention in turn axis, (4) teaching point only for teacher, and (5) turn axis image. Answers (1) to (4) were collected through open-ended questions and (5) were selected from the illustration. Open-ended questions were processed using frequency word analysis and co-occurrence network analysis. Results: The results showed that both amateur and professional dancers focussed on stable axis and passé positions, and professionals were more conscious of standardized skills in ballet, such as "turn-out" or "position," to determine aesthetically competent pirouettes. Amateurs and professionals had several different viewpoints they were conscious of when executing movements in 2 directions of turning. Moreover, their consciousness of the turn axis could be described as the line from the toe to the head, although it is from the centre of pressure to the centre of the mass in most previous biomechanics studies. Conclusion: This study suggested the elements of aesthetics during pirouette from the dancer's perspective can be the stable axis, height of passe, turn-out of both legs, arm position, spotting, and smoothness of finishing (landing).

Introduction: University dancers endure psychological and physical stress over the academic year which may impact their health-related quality of life (HRQoL) and sleep patterns. Previously, university dancers reported decreased HRQoL and poor sleep quality over one semester. Although some information exists on HRQoL and sleep among the dance population, there is limited data on the changes of these variables over an academic year. Thus, we examined (1) relationships between and (2) changes in HRQoL and sleep over an academic year in university dancers. Methods: Twenty-two university dancers (20.5 ± 8.8 years) completed the Short-Form 20 (SF-20) and Athlete Sleep Screening Questionnaire at 8 specific points over the 2021-2022 academic year. SF-20 scores were coded (scale = 0-100) with higher values describing better health. Five items summed to calculate the Sleep Difficulty Score (SDS) with higher scores describing worse sleep. Pearson correlations between HRQoL and sleep were run at each time point. Based on small-to-moderate correlations, two separate repeated measure ANOVAs followed by Bonferroni-pairwise comparisons analyzed changes in sum HRQoL and sleep over time (p ≤ 0.05). Results: Correlations between HRQoL and sleep were significant at 4 out of 8 time points (T4: r = -0.6, p = 0.004; T5: r = -0.5, p = 0.01; T7: r = -0.5, p = 0.02; T8: r = -0.6, p = 0.002). HRQoL and sleep changed during the study (HRQoL Greenhouse-Geiser results: F_(4.4,92.7) = 4.0, p = 0.004; partial η² = 0.2; SDS Sphericity-Assumed results: F_(7,147) = 7.9, p < 0.001; partial η² = 0.3). HRQoL changed from T1-to-T2 (p = 0.03), while SDS changed from T1-to-T2, T1-to-T3, T1-to-T6, T1-to-T7, T1-to-T8, T4-to-T7, and T5-to-T7 (range: p < 0.001 to 0.03). Conclusions: University dancers' sleep fluctuated more than HRQoL over the year. The first 8 weeks of the semester seem to be critical for university dancers as their HRQoL and sleep declined heading into midterm evaluations. Further research is needed to validate HRQoL measures in dancers. Practitioners may use this information to aid in the maintenance and improvement of overall well-being in their dancers.