Can Dance Improve Turning in People With Parkinson's Disease?

Objective: To investigate the effects of a dance intervention on selected functional parameters during the 180° turning phase of the Timed Up & Go (TUG) test in people with Parkinson's Disease (PwPD). Methods: Fifteen adults clinically diagnosed with idiopathic PD were allocated into dance intervention (DIG; n = 7 ; age 73 ± 2 years) and control (CG; n = 8; age 64 ± 5 years) groups. The dance intervention lasted for 3 months (1 hour, twice a week). At baseline, all participants completed the Unified PD Rating Scale-part III, the International Physical Activity Questionnaire-short form, and the Hoehn & Yahr scale. Pre- and post-intervention, the primary outcomes were measured (number of steps and time to complete the 180° turning phase of the TUG test) at 2 speeds (comfortable walking and as quickly and safely speed) while using the Xsens® 3D motion suit. The secondary outcome (girdle dissociation) was assessed by calculating the difference between pelvis and affected shoulder orientation in the transverse plane (dissociation angles) at each data point during the TUG test's 180° turning phase. Results: At participant's comfortable walking speed, the functionality during the 180° turning remained unaffected following the dance intervention. However, at participant's fast speed, the dance intervention group significantly reduced the number of steps with a large effect size, and the total time taken to complete the 180° turning with a medium effect size. Post-intervention, most participants in the dance intervention group reduced the affected shoulder and pelvic girdle dissociation and turned more "en bloc." Conclusion: Dance can improve selected functional parameters during the 180° turning at fast speed in PwPD. The current results should be considered in rehabilitation programs.

The effects of dance interventions on physical function and quality of life among middle-aged and older adults: A systematic review.

BACKGROUND: Fundamental physical functions such as postural control and balance are vital in preserving everyday life, affecting an individual's quality of life. Dance is a physical activity that offers health advantages across various life stages. Nevertheless, the effects of dance interventions on physical function, postural control, and quality of life among older adults have remained underexplored. The review aimed to examine the strength of evidence for dance interventions on physical function and quality of life among middle-aged and older adults. METHODS: A systematic review was conducted across four databases (PubMed, Cochrane Library, Web of Science, and Medline), focusing on studies involving more than four weeks of dance interventions. MeSH terms [dance or dance intervention or dance rehabilitation or dance movement] and [motor function or functional capacity or postural control or functional mobility or mobility or postural balance or balance or flexibility or gait] and [well-being or quality of life or life satisfaction] were utilized in the search. This review was registered in the PROSPERO database (CRD42023422857). Included studies were assessed using the Cochrane Risk of Bias. RESULTS: The search revealed 885 studies, and 16 met the inclusion criteria. The effects of various dance genres on physical functions and quality of life were compared. Most studies showed that dance intervention improved physical function, balance, postural control and quality of life. Dance intervention showed a high level of adherence compared to physiotherapy, self-care, conventional therapy, and aerobic and resistance exercise. CONCLUSION: In terms of improving physical function and quality of life, structured dance is a safe and relatively effective alternative to exercise. Note the effect of movement selection and intensity in the dance interventions. Dance with music may increase participants' interest, encouraging more physical activity among middle-aged and older adults.

Relative energy deficiency in dance (RED-D): a consensus method approach to REDs in dance.

Relative energy deficiency in sport (REDs) is a potentially severe, challenging, broad-spectrum syndrome with potential negative health and performance outcomes. The numerous research publications and International Olympic Committee consensus statements relating to REDs testify to the challenges faced in early identification or screening, diagnosis and management. Like sport, dance, in its simplest form, can be identified as an activity resulting in physiological energy demands and, as such, requires appropriate energy availability concerning energy expenditures. However, the specificity of physiological and psychological demands in dance must be considered when considering REDs. An environment where physical activity can exceed 30 hours per week and where culture may instil a value that thinness is required puts dancers at increased risk for REDs. The purpose of this study was to provide dance-specific guidance dance on this complex condition. An RAND/UCLA Delphi Panel method with nominal group technique was used to review the literature from REDs to evaluate how it may relate to dance. In addition to the EP, which was assembled from a multidisciplinary background with expertise in REDs and multiple genres of dance, six focus groups were commissioned. Four of the focus groups were drawn from the EP members and two additional focus groups formed by dancers and artistic leaders. These panels were used to guide the development of a RED-D diagnosis pathway, management plan and risk stratification and return to dance pathway. The dance-specific pathways are designed to be a practical tool for guiding and supporting clinicians managing RED-D. Furthermore, this paper represents an important focus of this area in dance and serves to stimulate discussion and further research within the sector.

Reliability, Variability and Minimal Detectable Change of the Isometric Mid-Thigh Pull in Adolescent Dancers.

INTRODUCTION: The importance and potential benefits of muscular strength in the adolescent's development for health and fitness has been demonstrated in the literature. Maximal muscular strength and its assessment, however, is not a primary assessment criterium in the selection of young talented dancers. METHODS: The present study evaluated the within- and between session reliability, variability, and minimal detectable change (MDC) of the isometric mid-thigh pull (IMTP). Thirty-five participants (female n = 17) participated in 2 identical assessments on the same day with 4-hour break in between. Three 3-second IMTP were performed, and the mean peak force value was used for the analyses. RESULTS: Within-session the ICC indicated excellent reliability (ICC = .99, 95% CI: 0.98-0.99). Between-session reliability was excellent (ICC = .98, 95% CI: 0.95-0.99). The standard error of measurement was 4% (48 N), the minimum detectable change was 12% (134 N) and the CV was 3%. There were no within-session statistically significant differences, but statistically significant differences between-session were observed (P < .001). Limits of agreement ranged from -121 N (95% CI -186 to -56 N) to 307 N (95% CI 243-372 N). CONCLUSION: The observed results demonstrated excellent within- and between sessions reliability, low variability, and an MDC of 12%. The consistency of the within-session scores suggest that peak force data may be obtained with single try efforts. The statistically significant difference in the means of the retest session, however, suggests that the time of the day or the time since entrained awakening may be affecting performance in adolescent dancers. The results of the current study indicate that the IMTP is a reliable assessment tool for maximal muscular strength in adolescent dancers.

Injury incidence and severity in Chinese pre-professional dancers: A prospective weekly monitoring survey.

OBJECTIVES: To determine dance injury incidence and severity in full-time Chinese pre-professional dancers. STUDY DESIGN: Prospective weekly online monitoring survey. METHODS: Respondents were asked to record all dance-injury incidences between September 2020 and July 2021 using a remote weekly self-report injury monitoring tool. An inclusive definition of injury was used in this study to record all injuries, even if they didn't cause a cessation of training. Data were excluded if respondents completed <90 % of the survey period and had over 3 consecutive weeks of missing data. RESULTS: 450 individuals from 11 different schools were included in the analyses. A total of 1157 injuries were reported over a 30-week academic year. Injury prevalence was 64.9 % and injury incidence was 5.51 injuries per 1000 h. Forty-eight percent of the injuries were minor severity and 41 % were of moderate severity, and the main injury sites were knees (0.89/1000 h), lower back (0.80/1000 h), feet (0.58/1000 h) and groin (0.56/1000 h). Female dancers reported significantly higher injury prevalence and injury incidence, and higher rates of moderate to severe injuries than males. The university group reported higher injury incidence than the adolescent group (p < 0.05), whereas the latter reported higher rates of moderate to severe injuries than the former (p < 0.001). CONCLUSIONS: The injury incidence found in this study (5.1 injuries/1000 h) is higher than most previous sets of data. Female dancers are at a higher risk of injury and reported higher levels of injury severity than male dancers, especially for the female adolescent group.

The Effects of a Single Session of a Rhythmic Movement Program on Selected Biopsychological Parameters in PD Patients: A Methodological Approach.

The aim of the present study is to examine the acute effects of a specially designed musicokinetic (MSK) program for patients with Parkinson's disease (PD) on (a) anxiety levels, (b) select kinematic and kinetic parameters, and (c) frontal cortex hemodynamic responses, during gait initiation and steady-state walking. Methods: This is a blind cross-over randomized control trial (RCT) in which 13 volunteers with PD will attend a 45 min MSK program under the following conditions: (a) a synchronous learning format and (b) an asynchronous remote video-based format. Changes in gait biomechanics and frontal cortex hemodynamic responses will be examined using a 10-camera 3D motion analysis (Vicon T-series, Oxford, UK), and a functional near-infrared spectroscopy (f-NIRS-Portalite, Artinis NL) system, respectively, while anxiety levels will be evaluated using the Hamilton Anxiety Rating Scale. Expected results: Guided by the rules of music, where periodicity is distinct, our specially designed MSK program may eventually be beneficial in improving motor difficulties and, hence, reducing anxiety. The combined implementation of f-NIRS in parallel with 3D gait analysis has yet to be evaluated in Parkinsonian patients following a MSK intervention. It is expected that the aforementioned intervention, through better rhythmicity, may improve the automatization of motor control, gait kinematics, and kinetics-supported by decreased frontal cortex hemodynamic activity-which may be linked to reduced anxiety levels.

The Effects of the 11+ Dance Neuromuscular Program on Jump Height and Lower Extremity Biomechanics in Female Adolescent Dancers: A Non-Randomized Controlled Pilot Trial.

INTRODUCTION: Neuromuscular warm-up programs, such as FIFA 11+ were developed as early as 2006. These programs have been effective in reducing the risk of injury in female athletes by decreasing the moments surrounding the knee and improving neuromuscular control during static and dynamic movements such as jumping and landing. In addition, they have been effective for improving jump height in soccer, volleyball, and basketball. METHODS: The effects of the 11+ Dance, a dance-specific neuromuscular warm-up program, was examined on jump height and lower extremity biomechanics during bilateral and single leg countermovement jumps in recreational dancers. Twenty female adolescents from 2 dance schools participated in this 2-centered 8-week controlled non-randomized trial. The intervention group (IG) performed the 11+ Dance program 3×/week for 8-weeks during the first 30-minute of their regularly scheduled dance classes. The control group (CG) continued with their regular dance classes routine. Ground reaction force and motion capture data were used to assess jump height and lower extremity biomechanics pre and post intervention. RESULTS: Both groups statistically increased their jump height (CG: Z = 1.89-2.45, P ≤ .0167; IG: Z = 2.18-2.76, P ≤ .0167). However, no statistical between group differences were observed (Z = 0.38-1.22, P > .05). During takeoff, the IG statistically reduced peak knee extension moments (t(18) = -3.04 to -3.77, P ≤ .0167) while increasing peak hip extension moments (t(18) = 2.16-2.79, P ≤ .05) and peak hip flexion angles (t(18) = 2.68-3.72, P ≤ .0167) compared to the CG. The IG also increased the hip flexion angles compared to the CG during landing (t(18) = 2.78-5.13, P ≤ .0167) while no systematic differences were observed in all other variables of lower extremity biomechanics. CONCLUSION: The reduced joint load at the knee observed during takeoff needs further investigation. Neuromuscular training, such as the 11+ Dance, is supported by numerous quality research. Due to its simplicity, the 11+ Dance may be feasible and beneficial to complement regular warm-ups in recreational dance practice.

Online Dance Injury Monitoring: The Efficacy of Weekly Reporting and Respondent Compliance Over a 30-Week Period.

BACKGROUND: Previous injury survey recall methods often use one-off questionnaires with varying periods of recall. These methods have proven to show injury incidence inaccuracies and limited information on injury etiology. PURPOSE: The present study aimed to examine the efficacy of a remote weekly self-report injury incidence and etiology tool. METHODS: Two online questionnaires were developed based on the "Fit to Dance 2" survey and sent to volunteers. The first questionnaire was sent once and asked for complete injury history information. The second questionnaire was sent to each respondent on a weekly basis and it focused on new injuries and their causes and whether injuries that occurred in previous weeks were still affecting their dancing. The online survey was opened for full-time dance students from September 2020 to July 2021. All weekly data for each respondent were combined with a unique reference code using their account names, students' numbers, and schools' names. The proportion of participants who drop out is defined as the measurement of outcome. RESULTS: A total of 756 respondents engaged in the survey from 16 different Chinese dance schools; the drop-out rate was 70.1%, with student respondents under 18 years old having a slightly lower drop-out rate than adult respondents (69%vs 71%). 33 respondents (4.4%) who completed all 30 weeks survey. These data allow other researchers to examine respondent compliance rates from a weekly survey. CONCLUSION: A reminder system and teacher engagement could potentially increase the response rate. For frequent completion questionnaires the design needs to be streamlined to increase compliance. It is concluded that the researchers would need to weigh reduced completion rates (<100%) against data efficacy to achieve generalizability.

Spinal Counts, Impact, and Partnering Movements in Ballet, Modern, and Hip Hop dance: A YouTube Video Analysis Study.

INTRODUCTION: Dancers have self-reported a link between spinal extension movements and low back pain (LBP). Researchers have not reported the total number or frequency that spinal movements occur in ballet, modern, or hip-hop dance classes or performances. The purpose of this study was to report the number of spinal movements dancers are exposed to in different dance environments. MATERIALS AND METHODS: We analyzed 65 dance videos on YouTube.com for dance movements within 7 dance environments: ballet class and performance, modern class and performance, and hip-hop breaking, ciphers (large groups), and battles ("1v1s"). Two reviewers recorded counts of spinal (spinal flexion, extension, lateral flexion, and rotation), impact (jumps, leaps, and falls), and partnering movements (lifts, catches, and leans). Data analyses were processed in Jamovi (the jamovi project, Sydney, Australia). We reported movement totals, percentages, frequency, ranges, means with standard deviations (SD), and medians with interquartile range (IQR). We calculated significant differences using Mann-Whitney U tests. RESULTS: Video length ranged from 3 to 141 minutes (mean ± SD: 38.4 ± 38.3, range: 138). the average spinal extension movements ranged from 2 ± 0.8 to 7 ± 9.6 movements per minute across genres. Modern dance class had the most spinal flexion (89 ± 53.6), rotation (60 ± 40.8), and lateral flexion (74 ± 20.7) movements. Ballet performance had the most spinal extension movements (77 ± 69.8), jumps (74 ± 48), and leaps (19 ± 18.2). Hip-hop breaking had the highest number of falling movements (2 ± 2.3). Partnering movements were only present in ballet performance, modern dance performance, and hip-hop breaking environments. CONCLUSIONS: Movements that increase LBP occur often in all 3 dance genres. Dancers can expect frequent exposure to spinal extension movements; therefore, we recommend strengthening back and core musculature for all dancers. We recommend that ballet dancers also strengthen their lower extremity muscles. For modern dancers, we recommend strengthening their obliques. For hip-hop dancers, we recommend increasing muscular power and muscular endurance.

Hip Hop Party Dance: Cardiorespiratory Profile and Responses to a Predefined Sequence.

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' VO2peak was 57.3 ± 12.7 ml·kg-1·min-1, and HRmax 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.

The Efficacy of Physical Fitness Training on Dance Injury: A Systematic Review.

Greater levels of physical fitness have been linked to improved dance performance and decreased injury incidence. The aim was to review the efficacy of physical fitness training on dance injury. The electronic databases CINAHL, Cochrane Library, PubMed, Web of Science, MEDLINE, China National Knowledge Infrastructure were used to search peer-reviewed published articles in English or Chinese. Studies were scored using Strength of the Evidence for a Conclusion and a risk bias checklist. 10 studies met the inclusion criteria from an initial 2450 publications. These studies offered physical fitness training for professional (n=3) and pre-professional dancers (n=7), participant sample size ranged between 5 to 62, ages from 11 to 27 years, and most participants were females. Assessment scores were classified as Fair (n=1), Limited (n=7), and Expert Opinion Only (n=2) and risk of bias scores ranged from 22.7-68.2%. After physical fitness training, 80% of studies reported significant benefits in injury rate, the time between injuries, pain intensity, pain severity, missed dance activities and injury count. This review suggests that physical fitness training could have a beneficial effect on injury incidence in dance. The evidence is limited by the current study methodologies.

Determining Pointe Readiness in Young Adolescent Female Dancers: A Systematic Review.

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.

Rhythmic cueing, dance, resistance training, and Parkinson's disease: A systematic review and meta-analysis.

Objectives: The aim of the present systematic review and meta-analysis was to synthesize evidence associated with the functional and clinical effectiveness of rhythmic cueing, dance, or resistance training (RT) on motor and non-motor parameters in Parkinson's Disease patients, and to provide a comparative perspective not offered by existing systematic reviews. Methodology: Eligibility criteria for selecting studies retained no restrictions in methodological design and included interventions of rhythmic cueing, dance, RT, and measurements of motor and non-motor parameters. Animal studies, reviews, editorials, conferences, magazines, and gray literature articles were excluded. Two independent investigators searched Cochrane Library, Medline, PubMed, and SPORTDiscus from the date of their inception until 1 June 2021. The ROBINS-I tool was employed for the non-randomized controlled trials, and the updated for Risk of Bias 2 tool of Cochrane Library used for randomized controlled trials. For meta-analyses, the RevMan 5.4.13 software was used. For incompatible meta-analysis studies, a narrative data synthesis was conducted. Results: A total of 49 studies included in the systematic review involving 3767 PD participants. Meta-analyses revealed that rhythmic cueing training assists gait velocity (p = 0.01), stride length (p = 0.01), and motor symptoms (p = 0.03). Similarly, dance training benefits stride length (p = 0.05), lower extremity function-TUG (p = 0.01), and motor symptoms (p = 0.01), whilst RT improves lower extremity function-TUG (p = 0.01), quality of life (p = 0.01), knee flexion (p = 0.02), and leg press (p = 0.01). Subgroup analyses have shown non-significant differences in gait velocity (p = 0.26), stride length (p = 0.80), functional mobility-TUG (p = 0.74), motor symptoms-UPDRS-III (p = 0.46), and quality of life-PDQ39 (p = 0.44). Conclusion: Rhythmic cueing, dance, or RT positively affect the examined outcomes, with rhythmic cueing to be associated with three outcomes (Gait, Stride, and UPDRS-III), dance with three outcomes (TUG, Stride, and UPDRS-III), and RT with two outcomes (TUG and PDQ-39). Subgroup analyses confirmed the beneficial effects of these forms of exercise. Clinicians should entertain the idea of more holistic exercise protocols aiming at improving PD manifestations.International Prospective Register of systematic reviews (PROSPERO) (registration number: CRD42020212380).

Perceived Severity and Management of Low Back Pain in Adult Dancers in the United States.

INTRODUCTION: Low back pain (LBP) lifetime prevalence in dancers reportedly ranges from 17% to 88%. Low back pain can have negative secondary consequences on dancers' lives and careers. Still, how LBP impacts dancer function and medical care-seeking behaviors and whether these issues differ across dance genres, is understudied.
Materials and Methods: Two hundred and eight-nine ballet, modern, and hip-hop dancers and teachers (median age: 20.3 years; range: 18 to 69 years) in the United States completed an online 24-question survey assessing LBP related self-reported injury history, impact on their lives, and management strategies. We defined LBP as occurrence of acute or chronic pain in the lumbar or sacral regions of the back.
Results: Two hundred and fifty-seven participants (88.9% of 289 total) reported at least one instance of LBP during their lifetime and 220 participants reported LBP in the prior 4 weeks. Of these 220, 72 (32.7%) had LBP severe enough to limit their activities of daily living. Of the 213 who had LBP and danced during that time, 89 (41.8%) reported that LBP limited their dancing. Pain intensity (median: 4 on a 0 to 10 scale, IQR: 3.0) and LBP prevalence were similar across dance genres. Dancers sought multiple medical professionals, most often chiropractors (n = 94, 33.8%), medical doctors (n = 77, 27.7%), and physiotherapists (n = 60, 21.6%). Ninety dancers (35.0% of those with LBP) never sought medical care. Dancers who did seek care reported higher pain intensities (median: 4, IQR: 3.8) than those who did not (median: 3, IQR: 3.0).
Conclusion: Overall, most participants did suffer from LBP. Low back pain negatively impacts dancers' everyday activities and dancing. Pain intensity and loss of function may impact care-seeking. Our findings highlight the need for all dance stakeholders to educate dancers about their health, provide resources for dancer health care, and proactively create an environment that supports injury reporting behaviors in dancers.

The Relationship of Year Group and Sex on Injury Incidence and Countermovement Jump in Adolescent Ballet Dancers: A Cross-Sectional Analysis.

INTRODUCTION: Pre-professional ballet training involves long training hours from an early age that could influence young dancers' physical performance and injury incidence. This cross-sectional analysis investigated the relationship of year group and sex with countermovement jump and injury incidence (primary outcome) in adolescent ballet dancers at a pre-professional dance school.
Method: Countermovement jump (CMJ) height was recorded at the start of the academic year for 179 participants (M = 68, F = 111) spread across eight year-groups. Injury etiology and incidence was prospectively recorded over a 6-month period (September through February) by the medical team using a time-loss definition.
Results: Between-subject statistically significant differences were reported for sex [F(1, 153) = 101.46; p < 0.001], year group [F(7, 153) = 12.57; p < 0.001], and sex*year group [F(7, 153) = 9.22; p < 0.001]. Mean CMJ across the year groups ranged between 24.7 to 41.3 cm for males and 23.5 to 25.1 cm for females. Injury incidence per dancer was 0.84 (CI: 0.13, 1.56) and injury incidence per 1,000 hours of dance was 1.94 (CI: 1.63, 2.25). No statistically significant differences between sexes or year groups were reported for injury incidence per 1,000 dance hours and time-loss. Hours dancing was statistically significantly positively associated with CMJ (r = .481, p < 0.05) and negatively associated with injury incidence (r = -.253, p < 0.05) for males; for females it was positively associated with time-loss (r = .254, p < 0.05).
Conclusion: Even though CMJ was cross-sectionally monitored, the expected increased physical abilities in males as they grew older and progressed through their training was observed. Females did not indicate a similar increase in their physical ability, but they seemed to become more susceptible to injuries as they grow older. The lack of this speculative physiological development for the females may be associated with the ballet-only approach in their training. The use of CMJ as an injury screening tool may be limited, however, it could still be used as a tool to monitor physiological and fundamental motor skill development of adolescent dancers, as jumping is an integral part of ballet.

Neuromuscular Training in Pre-Professional Ballet Dancers: A Feasibility Randomized Controlled Trial.

INTRODUCTION: It is well documented that there is high prevalence of injuries in pre-professional and professional ballet dancers. Current evidence from high in quality and quantity research on in- jury prevention in sport indicates that interventions can reduce injury risks by 30% to 50%. Injury prevention research in dance is limited. The aim of this study was to assess the feasibility (adherence, fidelity, and practicality) of a randomized controlled trial for the utilization of neuromuscular training in pre-professional ballet dancers.
Methods: A convenience sample of 22 pre-professional ballet dancers were randomized into an intervention and control group. The intervention group took part in a neuromuscular-based training workout, five times per week before the ballet class, for 10 weeks. The intervention was an adaptation of the FIFA 11+, an injury prevention intervention and is called 11+ Dance. The intervention consisted of low intensity bodyweight exercises that lasted 20 to 30 minutes performed daily.
Results: Intervention adherence was 38% ± 8%, with higher participation at the beginning of the study. Attendance for post-testing was low 45% and 36% for the intervention and control group, respectively, mainly due to injury. There were no adverse effects reported, however, the participants reported delayed onset muscle soreness at the beginning of the intervention, indicating that there may be a potential training effect. Fear of muscle hypertrophy and fatigue were also reported as reasons for attrition. The repeated measures ANOVA revealed statistically non-significant differences for the countermovement jump F(1, 9) = 0.36, p = 0.564, η² p= 0.04; reactive strength index F(1, 7) = 0.02, p = 0.885, η² p= 0.003; and the isometric mid-thigh pull F(1, 12) = 0.002, p = 0.967, η² p= 0.000.
Conclusion: The results of the study, together with the feedback from the participants, suggest that some protocol modifications are necessary for the feasibility of a randomized controlled trial in a pre-professional setting. The current trial has produced valuable information for the intervention frequency and load prescription.

Development of the Dance Fitness Indicator©: A High-Intensity Dance Fitness Test: A Preliminary Study.

OBJECTIVE: The aim of this study was to develop a contemporary dance technique-specific, high-intensity dance fitness test and carry out preliminary testing into measuring the physiological intensity and reliability. The choreography of the Dance Fitness Indicator© (DFI©) is based upon Humphrey/Limón, Graham, and Cunningham techniques and includes dance elements that relate to fitness elements, that increase in intensity over four levels designed to observe changes in heart rate (HR) and rate of perceived exertion (RPE) as the DFI© progresses. Each level lasts for 4 minutes, 16 seconds, with a 1-minute rest between each level; the full DFI lasts for 20 minutes, 12 seconds. METHODS: Twelve contemporary dancers (9 females, age 24±6.86 yrs; 3 males, age 20±0.58 yrs) were taught the DFI© in a familiarization session before undertaking two test trials, within a 1-week period. Dependent variables to measure intensity were heart rate (HR), rate of perceived exertion (RPE), and blood lactate (BLa). RESULTS: Data for level 4 during test 1 and test 2, respectively, were: HR 184±16.79 bpm vs 187±16.18 bpm; RPE 17 ±2.43 vs 17 ±2.12; and BLa 8.9 ±2.71 mmol/L vs 9.1±2.41 mmol/L. Reliability was calculated by determining the coefficient of variation from paired samples t-tests between test 1 and test 2, which demonstrated consistency/good reliability (<5%) for end BLa (3.2%), HR (1.7%), and RPE (0.9%). CONCLUSION: These preliminary results suggest that the DFI© requires a high physiological intensity demand, through movement-specific contemporary dance technique, relating to dance performance intensity, and is a reliable testing mode within a dance studio environment. It could also be used to assess dancers' physiological abilities to cope with high-intensity intermittent cardiovascular and technical demands of dance performance; however, further testing with greater numbers of subjects is recommended.

Impact Attenuation and Deformation Characteristics of Dance Floors on Jump Kinematics.

Specialist dance floors have been promoted to reduce impact forces and reduce lower limb injury for dancers. 18 trained female dancers carried out 70 continuous ballet jumps on 4 different surfaces wearing an XSENS suit. Three specialist dance floors, Floor A (64% force reduction), Floor B (67% force reduction), Floor C (no data) were compared to Floor D (vinyl-covered concrete - control). Dependent variables for each analysed jump (2,3,4, and 67,68,69) were ankle, knee, hip range of movement (ROM); lower and upper leg angular velocities and pelvis vertical acceleration. No main effects were reported for dance floor, first and last jump series. Comparison of the floors against Floor D reported a main effect for the dance floors (p=0.001), first and last jump series (p=0.001). Between-subject effects noted that ankle ROM was significantly greater for trials on floor A (p=0.007) compared to floor D. ROM data significantly decreased between the first and last jump series whilst vertical pelvis accelerations increased except for floor A. Within the current study, a foam backed vinyl floor (C) provided better shock absorption than floors with higher deformation characteristics (A and B) and none of the specialist dance floors performed better than vinyl covered concrete (D).

Prevalence and Risk Factors of Dance Injury During COVID-19: A Cross-Sectional Study From University Students in China.

Objectives: Although coronavirus disease 2019 (COVID-19) has transformed the training environment of dancers worldwide, little is known on how this has affected injury prevalence, causes, and risk factors. Methods: An online investigation involving Chinese full-time dance students was conducted (September-November 2020), which covered two 6-month periods just before and during the first COVID-19 lockdown. Results: 2086 students (19 ± 2.4 years) responded to the investigation. Injury prevalence dropped from 39.6% (before the lockdown) to 16.5% (during the lockdown) (p < 0.01). It was noted that a significant increase in injury severity during the lockdown was caused due to a 4.1% increase in moderate-to-severe injuries (p < 0.05). During the lockdown, the injuries on the lower back, feet, and shoulders decreased significantly (p < 0.01), but the knee, ankle, and groin/hip joint injuries remained the same. Fatigue and the recurrence of an old injury remained as the top two perceived causes of an injury between the two periods with the increase in an unsuitable floor (p < 0.01), a cold environment (p < 0.05), and set/props (p < 0.05). The fatigue degree of students decreased (p < 0.01) and their hours of sleep increased (p < 0.01) during the lockdown. Binary Logistic Regression analysis indicated that dance injury is associated with fatigue, the hours of sleep, and the actions taken if they suspect an injury during the lockdown (p < 0.05), but is only related to the time set aside for a cooldown and age before the lockdown period (p < 0.05). Conclusion: Although injury prevalence dropped significantly during the first COVID-19 lockdown in Chinese dance students, the main dance injury characteristics remained the same. Decreased fatigue and longer hours of sleep could explain the aforementioned drop in injury prevalence during the lockdown.

Associations between nutrition, energy expenditure and energy availability with bone mass acquisition in dance students: a 3-year longitudinal study.

Three years of study showed that female and male vocational dancers displayed lower bone mass compared to controls, at forearm, lumbar spine and femoral neck. Energy intake was found to positively predict bone mass accruals only in female dancers at femoral neck. Vocational dancers can be a risk population to develop osteoporosis. PURPOSE: To determine whether risk factors normally associated with low bone mass in athletic populations (i.e. nutrition intake, energy expenditure and energy availability) are significant predictors of bone mass changes in vocational dance students. METHODS: The total of 101 vocational dancers (63 females, 12.8 ± 2.2 years; 38 males, 12.7 ± 2.2 years) and 115 age-matched controls (68 females, 13.0 ± 2.1 years; 47 males, 13.0 ± 1.8 years) were monitored for 3 consecutive years. Bone mass parameters were measured annually at impact sites (femoral neck, FN; lumber spine, LS) and non-impact site (forearm) using DXA. Nutrition (3-day record), energy expenditure (accelerometer), energy availability and IGF-1 serum concentration (immunoradiometric assays) were also assessed. RESULTS: Female and male vocational dancers had consistently reduced bone mass at all anatomical sites (p < 0.001) than controls. IGF-1 did not differ between male vocational dancers and controls, but female dancers showed it higher than controls. At baseline, calcium intake was significantly greater in female vocational dancers than controls (p < 0.05). Male vocational dancers' fat and carbohydrate intakes were significantly lower than matched controls (p < 0.001 and p < 0.05, respectively). Energy availability of both female and male vocational dancers was within the normal range. A significant group effect was found at the FN regarding energy intake (p < 0.05) in female dancers. No significant predictors were found to explain bone mass differences in males. CONCLUSION: Our 3-year study revealed that both female and male vocational dancers displayed lower bone mass compared to controls, at both impact and non-impact sites. The aetiology of these findings may be grounded on factors different than those usually considered in athletic populations.