Journal of Dance Medicine & Science最新文献

Background: Jumping is fundamental to vocational ballet training, yet physiological metrics are rarely assessed, leaving teachers and students reliant on subjective appraisals of jump quality. The accuracy of these perceptual judgements and their relationship to objective performance remain largely unexplored in young dancers. Purpose: To establish teacher-referenced countermovement jump (CMJ) thresholds corresponding to 1-5 ordinal ratings of jump quality in adolescent ballet dancers, and to examine student-teacher agreement patterns across sex and developmental stages. Methods: In a cross-sectional study of 133 vocational ballet students (84 females, 49 males; aged 11-19 years), teachers rated jump quality (1-5 scale) during standardized ballet sequences while students self-rated their abilities. CMJ height was assessed via Optojump. Receiver operating characteristic analysis with Youden's J optimization derived sex- and age-specific thresholds mapping teacher ratings to CMJ cut-points (cm). Student-teacher agreement was evaluated using quadratically weighted Cohen's k, confusion matrices, and McNemar tests. Analyses were stratified by sex and year-group (Y7-9, Y10-11, Y12-14). Results: Teacher-anchored thresholds increased with age and were higher in males (M Y10-11: 31.5-37.6 cm across rating categories; F Y10-11: 25.6 cm for ratings ≥4). CMJ demonstrated moderate discriminative ability (AUCs 0.41-0.88), indicating meaningful but incomplete correspondence with teacher ratings. Student-teacher agreement was partial (k_w = 0.05-0.55), with no directional bias in females but systematic patterns in males: teachers rated older males approximately one category higher than self-ratings (median difference = 1, P < .01). DeLong tests confirmed consistent discriminative ability across groups (P > .05). Sensitivity analyses verified robustness to leg-length adjustment, teacher clustering, and outlier exclusion. Conclusions: Sex- and age-specific CMJ thresholds provide practical benchmarks for calibrating subjective judgements in ballet pedagogy. Moderate AUCs reflect the multi-dimensional nature of jump quality, encompassing aesthetic and technical elements beyond vertical displacement. Systematic student under-rating relative to teacher assessment, particularly among older males, highlights the need for pedagogical strategies supporting realistic self-appraisal alongside technical development.

Introduction: Understanding segmental coordination of the pelvis, ribcage, and head is essential for interpreting expert technique in rotation-dominant Latin dance movements. This study examined expertise-related differences in three-dimensional trunk coordination during the Rumba Cuban Rocks by comparing a former Japanese national champion with competitive male dancers. Methods: Seventeen inertial measurement units (IMUs; Xsens MVN Link) recorded pelvis, ribcage, and head kinematics during three consecutive Cuban Rocks across five trials. Horizontal-plane displacements and peak angular velocities were calculated, and the Champion Dancer's values were compared with group means using one-sample t-tests or Wilcoxon signed-rank tests, as appropriate. Results: The Champion Dancer showed significantly smaller medio-lateral pelvic displacement (0.237 ± 0.005 m vs 0.279 ± 0.003 m, P < .01) and larger horizontal-plane pelvic rotational peak angular velocity (3.003 ± 0.173 rad/s vs 2.380 ± 0.168 rad/s, P < .001), indicating a rotation-dominant strategy with reduced sway. Smaller antero-posterior ribcage displacement was also observed in the Champion Dancer (0.038 ± 0.005 m vs 0.057 ± 0.001 m, P < .01). A figure-eight-like ribcage trajectory, identified from visual inspection of the horizontal-plane trajectories, was observed in the Champion Dancer, although this feature was not quantitatively evaluated. Ribcage horizontal rotational peak angular velocity (1.622 ± 0.030 vs 2.186 ± 0.168 rad/s, P < .01) and lateral tilt peak angular velocity (0.485 ± 0.049 vs 0.791 ± 0.071 rad/s, P < .001) were significantly smaller, suggesting moderated transmission of pelvic motion to the upper trunk. Head displacement was markedly smaller, indicating superior stabilization. Conclusion: These findings indicate a hierarchical coordination pattern characterized by pelvis-driven motion, constrained ribcage movement, and high head stability. This study provides biomechanical evidence describing trunk and head coordination during a rotation-dominant figure, offering insight into expert technique and instructional practice in competitive Latin dance.

Objectives: Bone stress injuries (BSI) result in lengthy rehabilitation periods for professional and pre-professional ballet dancers. For dancers who sustain BSI, there is a high chance of recurrence, which may affect future dance participation and career opportunities. This research engaged stakeholders from a classical ballet company to co-create BSI prevention strategies. Design: Participatory action research. Methods: Stakeholder-researchers (n = 17) within a professional ballet company participated in four sequential focus group meetings. Their roles included: Artistic staff, current/former dancers, clinicians, community engagement, events, marketing, facilities management, and philanthropy. Meetings were recorded, transcribed, and coded thematically. Finally, the group drafted a BSI prevention proposal for the organisation. Results: Stakeholder-researchers felt improving health literacy for recreational dancers in the community was important, as there may be an onflow of poor health behaviours from the community level into to pre-professional and professional settings. Priorities for prevention in the professional setting were improving access to onsite health services, annual health evaluations, refining safeguarding policies, and investigating wearable technology. Priorities for the community included targeted BSI education for dancers, teachers, and families. The artistic process, poor nutrition, stress, lack of load monitoring strategies, and glorification of dancing despite injury, are barriers to BSI prevention in both professional and community settings. Systemic barriers such as funding, and community access to dance-informed health practitioners were identified. Dancers may not utilise health services for 'athletes', because they identify strongly as artists. Conclusion: Stakeholder-researchers collaborated through PAR to identify and prioritise strategies for BSI prevention. Health literacy surveys and ongoing systematic injury surveillance were recommended to evaluate intervention effects.

Introduction: Dance has been explored as an intervention for individuals with Parkinson's disease (PD), demonstrating potential motor and mobility benefits. However, gaps remain regarding standardized protocols that consider cultural aspects and adherence. Methods: This study assessed the feasibility, acceptability, and preliminary clinical outcomes of a forró-based dance program on gait and pain in individuals with PD. A pre-post interventional feasibility study was conducted with 29 individuals with PD (mean age 60.3 ± 6.7 years), of whom 24 completed the 12-week protocol. The program included structured forró dance classes focusing on motor coordination, weight shift, and rhythmic movement. Pain intensity, mobility, and gait (timed up and go [TUG]; freezing of gait questionnaire [FOG]; 6-minute walk test [6MWT]) were assessed before and after the intervention. Feasibility and acceptability were determined as the primary outcomes. Results: Feasibility included a consent rate of 73.91% and a data completion rate of 82.75%. Acceptability was high (adherence: 86%; satisfaction: 98%), with no severe adverse events (9.09% minor events). The cultural familiarity of forró likely contributed to engagement. Preliminary clinical outcome analysis (n = 24) showed pre-to-post mean differences of -3.9 (95% CI [-5.76 to -2.04]) for the FOG score, +69.9 m (95% CI [48.78-91.02]) for the 6MWT, and -2.8 s (95% CI [-5.63 to 0.03]) for the TUG. A reduction in pain intensity was also observed. Conclusion: The forró-based dance protocol was found to be feasible, acceptable, and safe, and provided key parameter estimates for clinical outcomes. Future research should focus on controlled trials with larger samples to evaluate its effectiveness and potential implementation in healthcare systems.

Background: Toe flexor muscles (TFMs) play a critical role in ballet, contributing to stability and force transmission during pointe work and jumps. However, traditional training may not provide sufficient stimuli to maintain or improve TFM strength. This randomized controlled trial examined the effects of two targeted toe flexor training interventions on TFM strength and jump performance in adolescent ballet dancers.

Methods: Forty-nine full-time vocational ballet students (age: 16.0 ± 1.2 years) were randomized into three groups (1:1:1). All students continued their regular dance and supplementary conditioning training. In addition, Group 1 performed foot-specific resistance training with a toe flexion device, Group 2 performed single-leg heel rises on an inclined board, and Group 3 served as controls. The 6.5-week intervention assessed maximal voluntary isometric contraction (MVIC) of the TFMs (primary outcome), with horizontal and vertical jump performance as secondary outcomes.

Results: Repeated-measures ANOVA revealed significant Group × Time interactions for all toe flexor strength outcomes (P < .001). Group 1 improved TFM strength by 15% to 16% (P < .001), exceeding minimal detectable change thresholds. Group 2 showed no meaningful change, while the control group exhibited a small but significant decline on the right side (P = .046). Horizontal jump performance improved across groups, with the largest effects in Group 1 (r = .82), though between-group differences were non-significant. Vertical jump outcomes showed minor, inconsistent improvements with no clear group advantage.

Discussion: These findings indicate that a short-duration, device-based foot training program can elicit meaningful gains in TFM strength and support functional performance. In contrast, dance training and general conditioning alone may be insufficient to preserve toe flexor capacity during periods of intensive training. Specific loading appears essential for maintaining foot strength in this population. This study highlights the potential of targeted, progressively loaded foot exercises for maintaining or improving foot strength in young dancers.

Introduction: Adolescent ballet dancers are considered a generally healthy population. Yet as they navigate their development within the dance environment, there is potential for challenges to their well-being. Aim: This qualitative study explored how adolescent ballet dancers perceive and experience well-being, and what supports or hinders it. In elevating the dancers' voices, this study aimed to gain a deeper understanding of their experiences to inform the practices of clinicians and educators who protect and promote adolescent dancer well-being. Methods: Eleven female dancers in middle adolescence, aged 14 to 17 years, from 2 dance studios in Ireland, participated in semi-structured interviews that were analyzed with Reflexive Thematic Analysis. Results: Participants defined well-being as an integration of emotional, physical, and mental health. Their insights revealed 4 core aspects of their lives that impact their well-being experience: External Supports, Personal Resolve, Motivation Towards, and Barriers. Participants described their perceptions of well-being through relational experiences, emotional states, and self-management. Teachers who showed care beyond technique and friends who offered camaraderie were seen as key supports. Mental strength was identified as an important personal aspect of well-being support. A strong emotional connection to dance and taking breaks from dance were perceived as motivational, while feelings of judgment were perceived as barriers. Conclusion: Findings underscore what is known about biopsychosocial adolescent development and demonstrate the value of hearing more directly from adolescent dancers as to what underpins, strengthens, or detracts from their well-being. Participants' insights offer practical, developmentally-attuned implications for supportive clinical and educational environments. By bringing adolescent dancers' voices to the forefront, this study reinforces the need for inclusive, student-centered research, and well-being support.

Introduction: Dance has been suggested as an alternative therapeutic modality in cardiac rehabilitation programs (CRP). Therefore, evaluating the physiological responses of the body during dance is necessary to provide information that will allows it to be practiced a safe and effective way. In this context, the objective of the current study was to evaluate and compare the cardiac autonomic modulation (CAM) of women with cardiovascular risk factors (CRF) during and after a dance-based cardiac rehabilitation session and a conventional cardiac rehabilitation session. Methods: In total, 19 women, with at least 1 CRF, participated in this non-randomized crossover clinical trial, consisting of 4 steps: I. Familiarization with the dance protocol (DP); II. DP session; III. Familiarization with the conventional protocol (CP); IV. CP session. The CAM was evaluated using heart rate variability, considering nonlinear methods: recurrence plot, debugged trend fluctuations, and symbolic analysis. For data evaluation, 2-way analysis of variance for repeated measures was used, P < .05. Results: During exercise, an effect of protocol was observed for most of indices. In the DP, higher values were recorded for DET, Alpha-1, and 0 V% indices, and lower values for 1 V% and 2 ULV% indices and for entropy measurements. During recovery, no differences were observed between protocols. Effects of the exercises were observed in the comparisons between moments for all indices, however, a similar pattern of recovery was found between DP and CP. Conclusions: Comparisons of the dance and conventional protocols revealed that CAM was similar in both approaches, while greater alterations in nonlinear dynamics were observed during the DP exercise. However, these alterations were not able to modify the recovery of the volunteers. Clinical Trial Registration: The study was previously registered on the clinicaltrials.gov platform under registration number: NCT04967235. https://clinicaltrials.gov/study/NCT04967235?locStr=Brazil&country=Brazil&cond=Cardiovascular%20risk%20factors&term=Heart%20Rate%20Variability&intr=Dance%20therapy&rank=1.

Purpose: The aim of the proposed randomized controlled study is to compare the effects and efficacy of a dance, a Tai Chi and a waiting list control group intervention over an 8-week period on physical functions and mental benefits among non-clinical adults aged between 18 and 60.

Method: A double-blind, randomized controlled trial will be adopted to evaluate the effects and efficacy of an 8-week dance intervention compared with Tai Chi and a control group on physical and mental benefits. Participants will be randomly assigned to 3 groups, dance, Tai Chi, and Control group, using stratified random sampling based on sex. Isometric Mid-thigh Pull (IMTP), Y-Balance test (YBT), Warwick-Edinburgh Mental Wellbeing Scale (WEMWBS), and The Brunel Mood Scale (BRUMS) are utilized for collecting physical and mental data. All measurements will be conducted by research assistants blinded to participants' group allocation and analysis will be carried out by statistician blinded to the group and test parameters.Expected result:Mental wellbeing parameters are predicted to be increasing during the learning phase and the physical parameters are predicted to have an improvement in the practising phase.

Introduction: The mechanism of foot injury in ballet dancers can be understood by measuring the forces exerted on the foot in pointe shoes. In this study, we aimed to reveal the vertical forces applied to the toes in a pointe shoe during ballet movements in a time series using a modified foot pressure sensor. Methods: Three dancers wore their pointe shoes equipped with sensors to replace their usual toe pads. They performed 2 tasks: (1) holding a pointe posture on the right leg for 5 seconds and (2) jumping 5 times on the right leg while on pointe, on a force platform. Their movements were captured using a 10-camera motion-capture system synchronized with the force platform and pressure sensor. Results: The force data for the bottom of the toe box, calculated by multiplying the pressure by the area, showed a correlation with the vertical ground reaction force measured using the force platform. Our results revealed that, during the jumping task, the highest forces were applied to the toe box, whereas in the standing task, the metatarsal area experienced greater forces than the toe box did. Significant individual variability was observed in other areas. Conclusion: This study demonstrates that the modified sensor effectively captures pressure variations with different movements, offering valuable insights for injury prevention and optimizing ballet techniques.