Journal of Dance Medicine & Science最新文献

Introduction: Wearable technology (WT) has become common place in sport. Increased affordability has allowed WT to reach the wrists and bodies of grassroots and community athletes. While WT is commonly used by sport populations to monitor training load, the use of WT among dancers and dance teachers is unknown. Therefore, the purpose of this study is to explore the perspectives of dancers, dance teachers, and dance parents on using WT in the dance studio environment. Methods: Dancers (aged 14+), dance teachers (aged 18+), and dance parents (with a child <18 years registered in a dance program) were recruited from local dance studios (including those offering vocational programs and/or professional training opportunities), and dance retail stores. Participants provided informed consent/assent and completed a one-time online survey about their attitudes, self-efficacy, motivations, barriers, and current practices of using WT in the studio. Results: Sixty-seven participants (19 dancers, 32 dance teachers, and 16 dance parents) completed the survey. Attitudes toward using WT were similar across all groups (mean score range = 34-38/45). Thirteen dancers (68%), 29 teachers (91%), and 7 dance parents reporting on behalf of their children (47%) were permitted to use WT in the studio. Smartwatches were the most common WT used in the studio by dancers (7/9) and teachers (13/17), while dance parents reported that their children primarily used wristband activity trackers (3/4). Among all groups, the primary reason for using WT was to track personalized training data, with calories, total duration, and heart rate being the most important perceived metrics for improving dancing. Conclusion: Across all groups, attitudes toward WT were modest. Prevalence of WT use in the dance studio varied, with wrist-based gadgets being the most common. As WT research continues in dance populations, it will be important for future studies to consider studio permissions as well as participants' existing WT use practices.

Introduction: There is a dearth of information about whether lesbian, gay, bisexual, transgender, queer/questioning (LGBTQ+) dancers, who often experience increased psychosocial risk factors, are at increased risk of engaging in harmful behaviors compared to their heterosexual cisgender counterparts. This study explores harmful behaviors dancers engage in according to their self-reported sexual orientation and gender identity (SOGI), utilizing the validated Risky, Impulsive, and Self-Destructive Behavior Questionnaire (RISQ).

Methods: Three hundred sixty-four dancers from 7 elite dance entities in New York were contacted by e-mail to participate in the study. Sixty-six participants completed the study through a virtual questionnaire. Chi-square, ANOVA and independent t-test were utilized to assess statistical differences among RISQ outcomes in 4 SOGI groups: Cisgender Heterosexual Female (n = 20); Cisgender Heterosexual Male (n = 7); LGBTQ+ Female (n = 19); and LGBTQ+ Male (n = 20).

Results: Chi-square comparing SOGI group frequency of participation within each of the RISQ behaviors revealed statistically significant difference with: difficulty stopping eating (P = .05); gambling illegally (P = .036); betting on sports, horses, or other animals (P = .036); buying expensive items that cannot be afforded at the spur of the moment (P = .019); and drinking 5 or more alcoholic drinks in 3 hours or less (P = .013). Between-group frequency comparison through ANOVA and independent t-test revealed: the LGBTQ+ Male group were 92% more likely to have unprotected sex with someone they just met or did not know well (P < .001) and 83% more likely to use hallucinogens, LSD, or mushrooms (P = .018); the LGBTQ+ Female and LGBTQ+ Male groups were 4.4 times more likely to buy drugs (P = .01) and 4.88 times more likely to think about killing themselves (P = .023); and both male groups were 12.8 times more likely to steal money (P = .006).

Conclusions: This study found significant difference in RISQ scores based on a dancer's SOGI. Harmful behaviors should be taken into consideration when working to improve dancer patient outcomes and quality of life.

Introduction: Professional ballet dancers load their hips in extreme ranges of motion and commonly report hip pain. Evaluating gluteal muscle size and quality may help guide exercise programs. Objectives of this study were to compare gluteal muscle size and quality (fatty infiltration) in ballet dancers compared to athletes; and to investigate the relationship between gluteal muscle size and quality, and reports of hip-related pain.

Methods: This study was a case-control design. Professional ballet dancers (current and retired, n = 49, mean age 35 years, range 19-63) and age and sex-matched athletes (current and retired, n = 49) underwent magnetic resonance imaging of both hips. Muscle cross-sectional areas (CSA) were obtained at standardized landmarks for gluteus maximus (GMax) and gluteus medius (GMed). Full muscle volume was calculated for gluteus minimus (GMin). Fatty infiltration was rated using the Goutallier classification system. Muscle size was compared between groups using linear mixed models. Fatty infiltration was compared using a mixed model binary logistic regression. Hip-related pain, participation status, limb side and sex were included as covariates.

Results: Ballet dancers had significantly larger GMax (upper P < .01, middle P < .01, lower P = .01) and GMed (level of anterior inferior iliac spine P < .01, greater sciatic foramen P < .01) CSA and larger GMin volume (P < .01), when normalized to weight. There was no difference in fatty infiltration ratings between dancers and non-dancing athletes. Retired dancers and athletes reporting hip-related pain were more likely to have fatty infiltration in GMax lower (P = .04).

Conclusion: Gluteal muscles are larger in ballet dancers compared to athletes suggesting high-level loading of these muscles. There is no relationship between hip-related pain and gluteal muscle size. Dancers and athletes have comparable muscle quality.

Background: Due to its multiple benefits in Parkinson's Disease, Dance has been a widely recommended activity in rehabilitation. However, there is a gap in the literature on the use of Brazilian sytles in rehabilitation protocols. This study aimed to compare the effect of 2 different protocols of Brazilian dance, samba and forró, and samba on motor aspects and quality of life of individuals with Parkinson's disease.

Methods: In a nonrandomized clinical trial lasting 12 weeks, 69 individuals with Parkinson's disease participated in the study: forró and samba group (FSG = 23), samba group (SG = 23), and control group (CG = 23).

Results: Significant improvements were found after SG intervention in the UPDRSIII and in the subitem quality of life mobility. In intra-group comparisons of FSG, significant differences were found in the subtype of quality of life discomfort. In the intergroup analysis, significant differences were found between CG, SG, and FSG in the communication sub-item, showing a greater increase in the scores of the groups that participated in the SG and FSG.

Conclusions: The findings of this study suggest that Brazilian dance practice is capable of improving the perception of some aspects of quality of life and motor symptoms in relation to controls in people with Parkinson's disease.

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.

Objectives: Pre-professional dance is high-risk, with injury incidence up to 4.7 injuries/1000 dance hours. Pre-season screening measures have been utilized to assess risk factors for dance-related injury, however normative values haven't been established for a pre-professional ballet population. The purpose of this study was to establish normative values of ankle and hip joint range of motion (ROM), lumbopelvic control, and dynamic balance pre-season screening measures for pre-professional ballet dancers.

Methods: 498 adolescent pre-professional ballet dancers [n = 219 junior division (194 female, 25 male; mean age: 12.9±0.9 year); n = 281 senior division (238 female, 41 male; mean age: 16.8±1.5 year)] participated in baseline screening tests across 5 seasons (2015-2019). Baseline measures took place at the beginning of each academic year: ankle ROM [dorsiflexion (deg); plantarflexion (PF) (deg)], total active turnout (TAT) (deg), lumbopelvic control [active straight leg raise (ASLR) (score); one leg standing test (OLS) (score)], and dynamic balance [unipedal balance (sec); Y-Balance Test (cm)].

Results: Percentiles for ankle dorsiflexion ranged from 28.2° (male senior division, 10th percentile) to 63.3° (female junior division, 100th percentile). For PF, percentiles ranged from 77.5 to 111.8° (male junior division, 10th percentile; male senior division, 100th percentile). Percentiles for TAT for all participants ranged between 121.1° and 131.0°. For the ASLR, the proportion of participants moving with compensation (pelvis shifting) was between 64.0% and 82.2%. For OLS, 19.7% to 56.1% of dancers had a positive score (hip hiking). Percentiles for dynamic balance ranged from 3.5 to 17.1 seconds (unipedal dynamic balance) and 75.8 to 103.3 cm (YBT composite reach score) across all groups.

Conclusion: The establishment of normative values of pre-season screening measures among a pre-professional ballet population can be used to determine areas to target during training, recognize individuals with possible injury risk, and inform return to dance protocols following injury. Comparison with other dancer/athletic populations will also provide insight into the performance of dancers and identify areas in need of improvement.

Introduction: Understanding the physical and mental health of collegiate dancers is important for developing appropriate screening protocols and treatment interventions. This study aims to provide descriptive data on the overall health, injury burden, and well-being of a group of collegiate dancers, including the interactions between injury, nutrition, and mental health, to provide insight for wellness screening and interventions in collegiate dance programs.

Methods: Members of the School of Dance at the University of Utah were sent an electronic general health survey. The survey included questions regarding medical history, family history, injuries, diet, sleep quality, symptoms of depression and anxiety, and history of eating disorders.

Results: Of the 231 dancers who received the survey, 198 responded (response rate = 85.7%). Fifty 2% of respondents had an active injury. Symptoms of depression and anxiety were common (35.4%), and 37.4% of the dancers were interested in receiving mental health support. Symptoms of depression and anxiety had a significant association with both a history of injury and active injuries (P = .033 and .039, respectively). History of eating disorder was also significantly associated with active injuries (P = .005). The most commonly injured body area was ankle or foot (n = 144, 72.7%), followed by lower leg or shin (n = 76, 38.4%), and knee (n = 61, 30.8%). Over a quarter of the dancers (n = 54, 27.3%) reported having trouble sleeping, and 9.1% reported having a history of eating disorder.

Conclusions: This study highlights the important interplay between mental health, sleep, nutrition, and injury. These results show that in a group of collegiate dancers, active injuries and mental health concerns are common, and that there are statistically significant associations between injury, nutrition, and mental health. These data provide insight into factors that affect dancer wellness and help inform future screening and intervention protocols for dance programs.

Introduction: Iron plays a significant role in energy production. However, it is not uncommon for athletes to be diagnosed with iron deficiency (ID), suggesting a correlation between performance and iron regulation. As a result, the International Olympic Committee has recommended iron screenings during health evaluations for elite athletes. Furthermore, athletes participating in esthetic sports are at increased risk for suboptimal iron intake due to disordered eating. Therefore, the purpose of this study was to investigate the distribution of serum ferritin (SF) in a cohort of elite ballet dancers and determine associations between vitamin D, anthropometric measures, stress injury, and dietary preferences.

Methods: Electronic health records of 40 elite ballet dancers (22 female, 18 male), age 19 to 38 years old, from the 2020 to 2021 pre-participation physical screening were examined. Chi squared comparisons were calculated to evaluate the association between SF and additional variables (ie, gender, age, height, weight, body mass index, vitamin D, stress injury history, and dietary preferences). SF values were compared to published normal and athletic population data.

Results: 58.97% of participants displayed normal or above SF values (>50 ng/ml), while 41.02% displayed minimal (<50 ng/ml) to depleted (<0.12/ng/ml) SF values. Approximately, 68% of the female dancers were ID and did not meet the minimal value needed for athletes. Females were more likely to have lower SF distributions (x² [4] = 15.6377, P = .004) compared to male dancers. Additionally, dancers who reported dietary preferences (ie, vegetarian) were more likely to display lower SF distributions (x²[4] = 13.3366, P = .010).

Conclusion: Over half of the female elite ballet dancers were ID which is consistent with current research. Females were at a significant higher risk compared to male dancers who reported dietary preferences. These findings suggest iron screenings should be considered in elite dancer populations.

Introduction: Research in court sports shows that factors which aid in extrinsic shock absorption, that is, flooring and footwear, can help reduce lower extremity injuries. However, since students and performers of ballet or most styles of contemporary dance cannot depend upon footwear, the only extrinsic factor to help them with shock absorption is flooring.

Methods: We investigated whether doing sauté on a low stiffness dance floor produced a difference in EMG output of the vastus lateralis, gastrocnemius, of soleus compared to a high stiffness floor. Average and average peak amplitude EMG output from 18 dance students or active dancers performing 8 repetitions of sauté on a low stiffness floor (Harlequin® Woodspring) was compared to a maple hardwood floor on concreted subflooring.

Results: The data showed a significant increase in average peak EMG muscle amplitude during jumping on the low stiffness floor compared to a high stiffness floor for the soleus muscle (P = .033) and a trend for increase average peak output for the medial gastrocnemius (P = .088).

Conclusion: The difference in average peak amplitude of EMG output is explained through the difference in force absorption between floors. With the high stiffness floor, more force of the landing was returned to the dancers' legs, but the low stiffness floor absorbed some of the force of landing the jump, and therefore muscles needed to contribute more to maintain the same jump height. The force absorption characteristic of the low stiffness floor may decrease injury rates in dance through causing an adjustment in muscle velocity. Rapid eccentric muscle activity carries the greatest possibility of musculotendinous injury and is experienced in lower body muscles controlling all joints during impact absorption, which includes landing of jumps in dance. If a surface can decelerate the landing of a high velocity dance movement, it also decreases the musculotendinous demand for high velocity tension generation.