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Ankle injuries are common among young ballet dancers. These injuries may be attributed to ankle instability, insufficient lower extremity strength, and poor balance control. The purpose of this study was to explore whether these dancers exhibit functional ankle instability and if their single-leg balance control and lower extremity muscle strength correlate with functional ankle instability and leg injuries. Twenty-one ballet dancers (aged 10 to 17 years) participated in the study. The Cumberland Ankle Instability Tool (CAIT) questionnaire was used to examine functional ankle stability. Isometric muscle strength of the major lower extremity muscles was measured with a digital hand-held dynamometer. Single-leg balance was evaluated with the Y-Balance Test (YBT) and three Athletic Single-leg Stability Test (ASLST) protocols. Lower extremity injuries (self-reported) within 6 months after testing were recorded for correlation analyses. Both dominant and non-dominant ankles of the subjects exhibited functional ankle instability (26.71 and 25.71, respectively). Raising the center of mass (passé and first arm position) during the ASLST did not significantly affect balance performance (p = 0.104). However, removing extrinsic visual feedback significantly decreased single-leg balance (p < 0.001). In general, there was low correlation (r ≤ 0.49) between muscle strength, CAIT, YBT, and ASLST scores with lower extremity injuries. It is concluded that for young ballet dancers lower extremity muscle strength and single-leg balance control may not be strong contributing factors to leg injuries. This study also suggests that functional ankle stability may not have a direct impact on single-leg balance, and ballet dancers rely heavily on extrinsic visual feedback for single-leg balance control. Teachers might consider minimizing extrinsic feedback to challenge ballet dancers when implementing training protocols for single-leg balance control.

Self-report wellness measures are used extensively in elite sport as valid indicators of the adaptive responses to training and performance of an athlete. Wellness parameters such as quality and quantity of sleep, muscle soreness, fatigue, and stress are monitored in professional sport via Athlete Management Systems (AMS) and self-report monitoring applications (App). However, the use of a monitoring App specifically for professional classical ballet dancers has not been tested. This study piloted a self-report App to measure wellness constructs in a professional ballet company. Three male and two female dancers volunteered to take part in the mixed-method study, entering daily wellness data, frequency of work-related activities, and injury status into an App on their smart phones. Via a focus group interview session, perceptions of wellness and experiences using the App were found to be favorable, with dancers reporting that the App enhanced awareness of their well-being. To further develop monitoring tools in professional ballet companies, it is recommended that the App be made specific to the wellness needs of dancers.

The ankles of ballet dancers are routinely under heavy loading that may lead to osteoarthritic changes. It would be clinically useful to identify such pathology as early as possible in a dancer's career. Therefore, the purpose of this study was to compare quantitative measurements in magnetic resonance (MR) images of the talocrural and talonavicular joints in ballet dancers and healthy non-dancers for use in formulating prediction of chronic injury and degenerative joint disease in these locations. Quantitative measurements in MR images of the talocrural and talonavicular joints were compared in 10 female ballet dancers, 10 healthy female non-dancers, and nine male ballet dancers. Fat-suppressed density-weighted proton, T1rho, and T2 mapping images were acquired with a 3.0 T MR scanner. Medial and lateral subchondral bone distance between the tibia and talus (MSBD and LSBD), axial navicular-talus axis angle (ANT angle), sagittal talar neck angle against the posterior talocalcaneal joint (TN angle), and curvature of navicular surface at the talonavicular joint were measured on sagittal images. The medial subchondral bone distance was found to be significantly larger in female dancers than female non-dancers (4.05 mm vs. 2.75 mm, p < 0.05), whereas there were no significant differences in LSBD (2.63 mm vs. 2.63 mm, p = 0.87). Axial navicular talus angles in female dancers were significantly larger than those in female non-dancers (38.9° vs. 24.3°, p < 0.05). There was a tendency for the TN angle to be smaller and navicular curvature (NC) to be larger in female dancers compared to female non-dancers, though the differences were not significant (TN angle: 16.6° vs. 22.3°, p = 0.09, and NC: 0.186 vs. 0.165, p = 0.28). There were no significant differences in T1rho or T2 values of talonavicular joint cartilage. These results show that the bony anatomy of dancers' ankles may adapt to the stresses placed on them by ballet.

Training load has been identified as a risk factor for musculoskeletal injury in sport, but little is known about the effects of training load in dance. The purpose of this study was to describe adolescent dancers' internal training load (ITL) and compare objective and subjective measures of ITL using heart rate (HR) training impulse methods and session Rating of Perceived Exertion (sRPE), respectively. Fifteen female elite adolescent ballet dancers at a vocational dance school volunteered to participate in the study. Internal training load data using HR and sRPE were collected over 9 days of multiple technique classes at the midpoint of the dancers' training year. Heart rate data were quantified using Edwards' training impulse (ETRIMP) and Banister's training impulse (BTRIMP), and sRPE was estimated from the modified Borg 0 to 10 scale and class duration. Descriptive statistics (median [M], and interquartile range [IQR]) were determined in arbitrary units (AU), and were as follows for all classes combined: ETRIMP: M = 134 AU (IQR = 79 to 244 AU); BTRIMP: M = 67 AU (IQR = 38 to 109); sRPE: M = 407 AU (IQR = 287 to 836 AU). The association and agreement between objective and subjective ITL measures in ballet and pointe class was assessed using Spearman correlations (rs) and adjusted Bland-Altman 95% limits of agreement (LOA), respectively, with alpha set at 0.05. A significant moderate positive correlation was found between ETRIMP and BTRIMP in pointe class (rρ = 0.8000, p = 0.0031). The mean difference (LOA) between ETRIMP and BTRIMP was 121 AU (33 to 210 AU) in ballet and 43 AU (-3 to 88 AU) in pointe. It is concluded that some, but not all, measures of ITL in elite adolescent ballet dancers are comparable. Additional research is needed to examine the utilization of ITL measures for evaluating dance-related injury risk, as well as the application of ITL to inform the development of effective injury prevention strategies for this high-risk population.

It is well known that sex differences exist in landing biomechanics in athletes, and these differences are purported to underlie a prevalence of traumatic knee injuries in females compared to males. However, it remains unknown if these differences also apply to artistic athletes such as dancers. The purpose of this study was to investigate sex differences in ground reaction forces (GRFs) between male and female dancers during single- and double-leg dance-specific landing movements. Fourteen pre-professional and professional ballet dancers (seven female and seven male) performed grand jeté (single-leg landing) and sauté (double-leg landing) jumps onto two force platforms. Visual3D was used to calculate the resulting GRF time-series, and MAT-LAB to select discrete variables of interest including peak vertical GRF, loading rate, landing duration, and vertical impulse. Paired t-tests were used to compare mean GRF variables between male and female dancers. During single-leg landing male dancers had smaller peak vertical GRFs (p < 0.01), greater time-to-peak GRF (p = 0.03), and smaller loading rates (p < 0.01) than female dancers. No differences were observed in vertical impulse during single-leg landing or in any variables during double-leg landing. These results indicate that sex differences in landing GRFs are most evident in single-leg landing and may underlie divergent injury rates in male and female dancers. Further investigation of relevant lower extremity biomechanics during single- and double-leg landing in male and female dancers should be conducted to identify the mechanisms underlying these distinct GRF profiles.

Ankle injuries are highly prevalent in ballet, with strength highlighted as a primary risk factor. To profile ankle strength, fourteen female ballet dancers (age: 19.29 ± 1.59 years) completed an isokinetic testing protocol comprising concentric eversion (CON

Purpose: Ballet dancers are required to achieve performance feats such as exciting and dramatic elevations. Dancers with a greater jump height can perform a wider range of skills during their flight time and implement more specific technical skills related to the aesthetic components of a dance choreography. New findings suggest the relationship between force and velocity mechanical capabilities (F-V profile) as an important variable for jumping performance. A new field method based on several series of loaded vertical jumps provides information on the theoretical maximal force, theoretical maximal velocity, theoretical maximal power, and the imbalance between force and velocity (F-VIMB). The purpose of this study was to observe the effects of 9 wk of individualized F-V profile-based training during countermovement jumps (CMJs) in female ballet dancers. Methods: CMJ and mechanical outputs of 46 dancers (age = 18.9 [1.1] y, body mass = 54.8 [6.1] kg, height = 163.7 [8.4] cm) were estimated in a pre–post intervention. The control group (10 participants) continued with the standardized training regimen (no resistance training), whereas the experimental group (36 participants) performed 2 sessions over 9 wk of a training plan based on their F-V profile. Results: The experimental group presented significant differences with large effect sizes in CMJ height (29.3 [3.2] cm vs 33.5 [3.72] cm), theoretical maximal force (24.1 [2.2] N/kg vs 29.9 [2.8] N/kg), and theoretical maximal velocity (4 [0.6] m/s vs 3.2 [0.5] m/s). Significant differences with a very large effect size were found in F-VIMB (43.8% [15.3%] vs 24.9% [8.7%]). Conclusion: A training program addressing F-VIMB is an effective way to improve CMJ height in female ballet dancers.

Jumping ability has been identified as one of the best predictors of dance performance. The latest findings in strength and conditioning research suggest that the relationship between force and velocity mechanical capabilities, known as the force-velocity profile, is a relevant parameter for the assessment of jumping ability. In addition, previous investigations have suggested the existence of an optimal force-velocity profile for each individual that maximizes jump performance. Given the abundance of ballistic actions in ballet (e.g., jumps and changes of direction), quantification of the mechanical variables of the force-velocity profile could be beneficial for dancers as a guide to specific training regimens that can result in improvement of either maximal force or velocity capabilities. The aim of this study was to compare the mechanical variables of the force-velocity profile during jumping in different company ranks of ballet dancers. Eighty-seven female professional ballet dancers (age: 18.94 ± 1.32 years; height: 164.41 ± 8.20 cm; weight: 56.3 ± 5.86 kg) showed high force deficits (> 40%) or low force deficits (10% to 40%) regardless of their company rank. Our results suggest that dance training mainly develops velocity capabilities, and due to the high number of dramatic elevations that dance performance requires, supplemental individualized force training may be beneficial for dancers. The individualization of training programs addressed to the direction of each individual's imbalance (high force or low force) could help dancers and their teachers to improve jump height and therefore dance performance.

Background: Prevalence and severity of symptoms related to muscle and joint pain seem to be high in most dancers. Hypothesis: There will be a worse quality of life related to foot health for ballet dancers compared with nondancers. Study Design: Case-control study. Level of Evidence: Level 4. Methods: A sample of 156 women was recruited from a clinic of podiatric medicine and surgery. Self-reported data were measured by the Foot Health Status Questionnaire (FHSQ), which has 33 questions that assess 8 health domains of the feet and general health, namely, foot pain, foot function, general foot health, footwear, general health, physical activity, social capacity, and vigor. Results: Statistically significant differences ( P < 0.05) were shown for foot pain, foot function, foot health, and general health, which together revealed a worse foot health–related quality of life (lower FHSQ scores) but a better general health (higher FHSQ scores) for ballet dancers compared with nondancers. The remaining domains did not show statistically significant differences ( P > 0.05). According to multivariate linear regression models ( P < 0.05), the practice of ballet dance (group) was the only independent variable that predicted the dependent variables, such as foot pain ( R2 = 0.052;β = +8.349), foot function ( R2 = 0.108; β = +11.699), foot health ( R2 = 0.039; β = +10.769), and general health ( R2 = 0.019; β = −6.795). Conclusion: Ballet dancers showed a negative impact on quality of life related to foot health but better overall quality of life (general health) compared with nondancers. Clinical Relevance: Paying attention to a dancer’s foot health could provide important benefits for the dancer’s foot health and physical practice of dance.

OBJECTIVES: Some forefoot shapes are ideal for pointe work in ballet. Egyptian-type, with the hallux being longest and the remaining toes decreasing in size, and Greek-type, with the second toe longer than the hallux, are considered less optimal for pointe work. Square-type, with the second toe the same length as the hallux, is considered optimal. This study compared postural stability in the bipedal stance, demi pointe, and en pointe between ballet dancers with the two toe types using a stabilometer. METHODS: This study included 25 Japanese ballet academy dancers who had received ballet lessons for at least 6 years. Toes were categorized into Egyptian-type (n=14) and square-type (n=11). Bipedal stance, demi pointe, and en pointe were tested. Center of pressure (COP) parameters were calculated from ground-reaction forces using two force plates: total trajectory length (LNG), velocities of anterior-posterior (VAP) and medial-lateral directions (VML), and maximum range displacement in the anterior-posterior (MAXAP) and medial-lateral directions (MAXML). Mann-Whitney U-tests were used to examine differences in COP parameters. RESULTS: There were no differences in parameters during bipedal stance or demi pointe. However, dancers with Egyptian-type toes had significantly greater LNG (p

Background Since ballet dancers begin their training before skeletal maturity, accurate and non-invasive identification of cartilage diseases is clinically important. Angle-dependent analysis of T1rho and T2 sequences can be useful for quantification of the composition of cartilage. Purpose To investigate the angle-dependent T1rho and T2 profiles of ankle cartilage in non-dancers and dancers. Material and Methods Ten female non-dancers, ten female dancers, and 9 male dancers were evaluated using T1rho and T2 mapping sequences. Manual segmentation of talar and tibial cartilage on these images was performed by two radiologists. Inter- and intra-rater reliabilities were calculated using intraclass correlation coefficients (ICCs) and Bland–Altman analysis. Mean thickness and volume of cartilage were estimated. Angle-dependent relaxation time profiles of talar and tibial cartilage were created. Results ICCs of the number of segmented pixels were poor to excellent. Bland–Altman plots indicated that differences were associated with segment sizes. Segmented cartilage on T1rho demonstrated larger thickness and volume than those on T2 in all populations. Male dancers showed larger cartilage thickness and volume than female dancers and non-dancers. Each cartilage demonstrated angular-dependent T1rho and T2 profiles. Minimal T1rho and T2 values were observed at approximately 180°–200°; higher values were seen at the angle closer to the magic angle. Minimal T2 value of talar cartilage of dancers was larger than that of non-dancers. Conclusion In this small cohort study, regional and sex variations of ankle cartilage T1rho and T2 values in dancers and non-dancers were demonstrated using an angle-dependent approach.

Ballet dancers need to constantly improve their performance. Several studies show that an internal focus (on body movements) leads to inferior motor performance relative to an external focus of attention (on the movement effects), but the majority of dancers usually adopt an internal focus. It is not clear if the benefits of an external focus are relevant for form-based tasks performed in a ballet.

Using electrocardiography and echocardiography, we screened elite men and women ballet dancers for abnormal cardiovascular conditions using an observation design with blinded clinical analysis of cardiac function tests. Fifty-eight (females

Due to frequent movements involving extreme hip amplitudes, ballet dancers often present with hip pain and chondrolabral lesions as seen in femoroacetabular impingement. The lesions appear even with normal anatomy. Diagnosis is often delayed, and treatment is challenging, especially in skeletally immature patients. This study reports the case of an adolescent ballet dancer suffering from a large symptomatic labral tear. The literature has also been reviewed for context regarding the pathophysiology and current therapeutic management of these injuries.

Despite various approaches to measuring ballet dancers' turnout, no standardized method for doing so has yet been estab- lished. Here a newly designed rotational goniometer (RGM) for assessing ballet dancers' functional turnout is evaluated. Twenty experienced female ballet dancers participated in the study. Measurements of the dancers' turnout were taken three times in each of the following conditions: 1. while standing on the RGM device (RGMT); 2. as if the participant was in a ballet class (CT); and 3. performing an active external rotation of the lower extremities in the supine position (AT). The angles obtained in the three trials in each condition were averaged and the results of the three conditions were compared. The mean angle of RGMT (RGMTangle: 103.89° ± 15.2°) was significantly smaller than those of the CT (CTangle: 128.7° ± 15.1°) and AT (ATangle: 110.09° ± 17.6°) conditions (p < 0.05 and p < 0.01, respectively). The greatest angle (i.e., the CTangle) is influenced by both friction and weightbearing. The ATangle is released from weightbearing, unlike the RGMTangle. Positive correlations were revealed between the RGMTangle and the ATangle (r = 0.78, p < 0.01) and between the RGMTangle and the CTangle (r = 0.57, p = 0.05). These findings demonstrate that the novel RGM device, characterized by elimination of friction and full weightbearing, is useful for assessing ballet dancers' functional turnout.

Several classical dance complex movements, such as pointe, require body weight to be supported properly to avoid risk of foot injury. Regarding the choice of toe cap for pointe shoes, it is unclear which type can better alleviate pain symptoms and toe deviation angle in dancers. The aim of the current crossover study was to investigate the acute effect of using different types of toe caps among well-trained professional dancers on pain perception and toe deviation angle. Ten young female professional dancers volunteered to participate in the study. Each participant was tested during two separate sessions with an interval of 72 h in between. Participants were tested in the two sessions with a standard commercial or a customized prototype toe cap, always with pointe shoes, and in randomized order. An anteroposterior X-ray examination was performed separately for each participant and a visual analogue scale for pain perception was administered following each situation (with a standard commercial or a customized prototype toe cap). Significant amelioration was obtained when a customized toe cap prototype was used both for toe deviation angle and for visual analogue scale. Use of a customized toe cap prototype compared to a standard one may acutely reduce both toe deviation angle and pain in elite female professional dancers.

Injuries involving the first metatarsophalangeal joint and its associated structures are common, especially in athletes. However, injuries to the hallucal sesamoid complex constituted only 3% of all podiatric sports medicine injuries reported by Agosta. This case study reports a female ballet dancer with an isolated fibular sesamoid retraction injury that presented with a history of chronic microtrauma secondary to overuse. When consulting epidemiologic studies of forefoot injuries involving the hallucal sesamoid complex, we were unable to find a single instance of an isolated retraction of the fibular sesamoid resulting from chronic use, demonstrating the unusual nature of this case.

AIMS: To compare the differences in bone mineral density (BMD) at loaded and non-loaded skeletal sites in professional ballet dancers. We hypothesized that in both male and female elite ballet dancers, a significant difference in BMD will be observed between impact and non-impact sites. METHODS: 44 elite ballet dancers, 22 men (age 26.4±5.9 yrs) and 22 women (age 24.9±5.3 yrs), were examined. BMD measurements were performed using dual-energy x-ray absorptiometry at three skeletal sites—forearm (FA), lumbar spine (LS), and femoral neck (FN)—and analyzed using t-tests, ANOVA, and linear regression models. Information about career duration, training volume, health habits, and menstrual disorders (women) was collected. RESULTS: Z-scores for LS and FN were significantly higher in men than in women. However, Z-scores for FA were similar in men and women and fell below the expected range for age (

Overuse pathologies are prevalent in ballet injury. Ten amateur ballet dancers (age: 23.20 ± 3.08 years) completed a progressive 5-stage choreographed routine on two consecutive days. Tri-axial accelerometers positioned at C7 and the dominant and non-dominant lower-limb were used to calculate accumulated PlayerLoadTM (PLTOTAL) and uni-axial contributions of the anterior-posterior (PLAP), medial-lateral (PLML), and vertical (PLV) planes. PLTOTAL increased significantly (p = 0.001) as a function of exercise duration within-trial, however there was no significant change between trials (p = 0.18). PLTOTAL at C7 was significantly (p = 0.001) lower than both lower-limbs, with no bilateral asymmetry evident (p = 0.97). Planar contributions to PLTOTAL were significantly greater in PLV than PLAP and PLML (p = 0.001). PlayerLoadTM demonstrated within-trial sensitivity to the progressive routine, however no residual fatigue effect was observed between trials. The results of this study suggest that accelerometers have efficacy in athlete monitoring and injury screening protocols, however unit placement should be considered for practical interpretation.

Posterior ankle impingement syndrome (PAIS) involves pain at the posterior as- pect of the ankle, due in dancers largely to repetitive hyperplantarflexion. In daily practice, corticosteroid injection is often used to relieve the pain of PAIS, but little has been recorded with regard to its effectiveness. The primary objective of this study was to determine the ef- fect on pain of corticosteroid injections in professional and elite student ballet dancers with PAIS. The secondary ob- jectives were to evaluate the prevalence of PAIS, the duration of the effect of injection, patient satisfaction with the effect of injection, time to return to class and performance, and ability to dance after injection. All members of the Dutch National Ballet and the National Ballet Academy Amsterdam received a self-administered questionnaire focused on the use and effect of corticosteroid injections in the treatment of PAIS. The response rate was 61% (77 of 126). Of the included dancers, 38% (29 of 77) had suffered from PAIS, and 38% (11 of 29) had received at least one injection. The numeric rating scale (NRS) was used to assess the severity of pain before and 2 and 6 weeks after injections. The median NRS pain before injection was 9.0 (IQR 8.0-9.5), 3.0 (IQR 0.5-6.5) 2 weeks after injection, and 3.0 (IQR 0.5-6.0) 6 weeks after injection. Overall median NRS satisfaction with the effect of injection was 7.0 (IQR 0-10), and satisfaction with the duration of the effect was 5.0 (IQR 2.0-10). It is concluded that there is a high prevalence of PAIS in ballet dancers and corticosteroid injections are regularly used for pain reduction with good results.

usc Objectives: to compare the deep hip external rotator (DHER) muscle (piriformis, gemelli, quadratus femoris (QF)) cross-sectional area (CSA) in dancers and athletes and evaluate the relationship between DHER size and hip pain. Study design: cross-sectional study. Setting: elite ballet and sport. Participants: 33 professional ballet dancers and 33 age and sex-matched athletes. Main outcome measures: CSAs of piriformis, gemelli and QF on magnetic resonance imaging (MRI). Hip pain scored with the Copenhagen Hip and Groin Outcome Score (HAGOS): Hip pain was categorised as ‘yes’ if HAGOS pain score was 0.05), and CSAs were not associated with hip pain. Male and female dancers had similar sized DHER muscles. In athletes, CSA of piriformis was 55% (p = 0.02, Cohen's d(95%CI) = 0.98 (0.26,1.71)) and the gemelli were 34% (p = 0.03, Cohen's d(95%CI) = 0.98 (0.26,1.70)) larger in men than women; QF was 36% larger (p = 0.08, Cohen's d(95%CI) = 0.77 (0.06,1.48)). Conclusion: although ballet dancers perform in external rotation, their DHER are no larger than athletes and muscle size was not associated with hip pain. Refereed/Peer-reviewed

Background The unique repetitive nature of ballet dancing, which often involves transgressing endurance limits of anatomical structures, makes dancers prone to injury. The following systematic review aims to assess the effectiveness of physiotherapy interventions in the treatment of injuries in ballet dancers. Methods The review was performed in line with the PRISMA statement on preferred reporting items for systematic reviews and meta-analyses. Six electronic databases (PubMed, Ovid Embase, Cochrane, Medline, PEDro, Google Scholar) were queried. The study populations comprised active ballet dancers and/or ballet school attendees with acute and chronic injuries and those with persistent pain. There were no restrictions regarding age, sex, ethnicity or nationality. The Modified McMaster Critical Review Form for quantitative studies was used to assess the methodological quality of the studies reviewed in accordance with the relevant guidelines. Results Out of the total of 687 articles subjected to the review, 10 met the inclusion criteria. Diverse physiotherapeutic interventions were described and effectiveness was assessed using different parameters and measurements. Overall, the results indicate that physiotherapy interventions in ballet dancers exert a positive effect on a number of indices, including pain, ROM and functional status. Conclusions Due to the small amount of evidence confirming the effectiveness of physiotherapeutic interventions in ballet dancers after injuries and methodological uncertainties, it is recommended to improve the quality of prospective studies.

This study explored transient characteristics of body sway during single-leg quiet stance in young ballet dancers (n=41) and young healthy adults (n=58). We compared the groups in terms of center of pressure (CoP) parameters (CoP velocity and amplitude, averaged across the duration of the 30-s trial), and the transient characteristics of the corresponding parameters, which were expressed as relative differences between the 1st and 2nd, and the 1st and 3rd 10-second interval within the trial (DIF_21 and DIF_31, respectively). Ballet dancers exhibited superior quiet stance postural control (2/5 parameters), as well as different transient behavior (3/5 parameters for DIF_21, and none for DIF_31). Specifically, the ballet dancers reduced body sway more during the 2nd interval, resulting in lower DIF_21 for CoP velocity (total and anterior-posterior) andCoP amplitude(medial–lateral) (effect size=0.42–0.54). The correlations between individual CoP parameters and the corresponding DIF_21 and DIF_31 were very small or trivial (r&nbsp

OBJECTIVE: In high-performance sport, the use of self-report measures is expanding. The exploration of wellness states in response to training and performance requires further investigation for professional ballet dancers and athletes. This study therefore aimed to: compare wellness scores between professional ballet dancers and athletes in training and performance; report frequency of self-reported modified participation during training and performance; and report frequency of self-reported inability to participate due to pain and illness in dancers and athletes. METHODS: Fourteen professional ballet dancers (mean 26 yrs, SD 2.6) and 14 sex- and age-matched professional athletes (mean 27.7 yrs, SD 2.9) recorded daily wellness (fatigue, stress, sleep quality and quantity), participation (full, rest, modified, or unable to participate) and activity (performance, training) into a wellness application on their smart phone over a 4-month period. Mixed factorial ANOVAs were conducted to assess the interaction between group (ballet dancers and athletes) and activity (performance and training) on the dependent variables (stress, fatigue, sleep quality, and sleep quantity). RESULTS: Stress and fatigue levels were higher for both dancers and athletes during performance compared to training periods. Dancers recorded lower sleep quantity than athletes, with no difference in sleep quality. Modified participation appears more common in dancers compared to athletes. Dancers and athletes were rarely unable to train or perform/compete over the 4 months. CONCLUSION: Self-reported wellness scores appear sensitive to activity type and can provide valuable information to guide intervention and recovery strategies. Further research on the impact of poor wellness on performance, illness, and injury in professional ballet is warranted.

AIMS: Professional ballet dancers are at risk for degenerative knee cartilage changes. In the current study, we evaluated the knee cartilage with T2 mapping methods in professional ballet dancers and healthy controls and investigated possible differences of T2 values between these groups. METHODS: We included healthy dancers with 5−20 years of professional ballet dancing experience and sex-matched healthy controls without knee pathology. T2 values of the knee cartilage were measured from axial, coronal, and sagittal images. The values were measured by free hand region of interest (ROI). RESULTS: The study population consisted of 44 people (22 dancers, 22 controls), with mean age of 25.57 ± 5.53 yrs. We found no significant relationship between sex and T2 values. We detected a significant positive correlation between age and T2 values for patellofemoral joint cartilage. T2 values of patellofemoral and tibiofemoral joints of dancers were significantly higher. Mean T2 values of patellofemoral joint were around 32 in all planes in dancers and around 12 in controls (p

The purpose of this study was to compare lower extremity (LE) biomechanics and muscle activity between 'new' and 'dead' pointe shoes in professional female ballet dancers performing relevé and arabesque. We compared sway area, peak ankle moments, and tibialis anterior and medial gastrocnemius muscle activation amplitudes. Nine ballet dancers participated (age = 22.2 ± 2.2 years, height = 163.2 ± 6.3 cm, body mass = 50.8 ± 6.5 kg) executed three trials of relevé and arabesque on pointe shoes under two conditions: 'dead' (108-144 training hours) and 'new' (3-36 training hours). While wearing 'dead' pointe shoes, dancers had significantly higher sway area during both relevé and arabesque (

Objectives To compare the cross-sectional area (CSA) of hip external rotators, obturator externus (OE) and obturator internus (OI), in ballet dancers and nondancing athletes, and evaluate the relationship between obturator muscle size and hip pain. Design Case-control study. Setting Elite ballet and sport. Participants 33 male and female professional ballet dancers and 33 age and sex-matched athletes. Main outcome measures CSA's of OE and OI measured on magnetic resonance imaging (MRI) of one hip. Hip pain was scored with the Copenhagen Hip and Groin Outcome Score (HAGOS): HAGOS pain score of 100 was defined as no pain and a score less than 100 was defined as pain. Participants weight and height. Results Estimated marginal mean CSA of OE was 14% larger in dancers than athletes (p = 0.01, ηp2 = 0.1); the size of OI was similar (p > 0.05). Men and women in both groups had similar sized OI and OE. There was no interaction between the estimated marginal mean CSA of either obturator and hip pain. Conclusions It appears that ballet selectively increases muscle size of OE, but not OI. Obturator size was not related to mild hip pain, as OE and OI size was similar in dancers and athletes with and without pain.

Patellar tendon pathology appears to develop in young athletes. It is not known how this tendon develops through adolescence. This longitudinal study investigated proximal patellar tendon development during the adolescent growth spurt in young ballet dancers and identified whether puberty (estimated by maturity offset) had an effect on tendon development. Fifty two dancers (32 female and 20 male dancers, ages 11-18 at baseline) had ultrasound images of their tendons every 6 months for 2 years. Changes in tendon size (anterior-posterior diameter) on grayscale images and echogenicity, as quantified using ultrasound tissue characterization, were recorded each time. Maturity offset was calculated used to estimate peak height velocity (adolescent growth spurt). Maturity offset did not affect effect tendon composition before peak height velocity; however, after participants passed peak height velocity, maturity offset increased the composition of stable echopattern (P < .05): a 4% differential increase in type I echopattern, indicative of normal tendon structure, and a decrease in type III echopattern (more disorganized echopattern) by 0.7% per year. Anterior-posterior thickness increased by 0.2 mm/y (P < .05) measured 2 cm below the patella. Following peak height velocity, the proximal patellar tendon attachment increased in thickness and demonstrated a more stable echopattern representative of aligned fibrillar structure. Future research is required to further understand this normal maturation and the factors that support this process, with the aim of reducing the development of patellar tendon pathology in the adolescent jumping athlete.

To determine the differences in the lower limb landing biomechanics of adolescent ballet dancers compared to non-dancers when performing a hop and a stop jump task.Cross-sectional.Laboratory.Thirteen adolescent female ballet dancers (11.8 ± 1.1 years) and 17 non-dancers (10.9 ± 0.8 years) performed hop and stop jump tasks.Vertical ground reaction force, and three-dimensional ankle, knee and hip joint angles and moments during the landing phase.Dancers displayed greater sagittal plane joint excursions during the hop and stop jump at the ankle (mean difference = 22.0°, P 0.001, 14.8°, P 0.001 respectively), knee (mean difference = 18.1°, P = 0.001, 9.8°, P = 0.002 respectively) and hip (stop jump task; mean difference = 8.3°, P = 0.008). Dancers displayed a larger hip extensor moment compared to non-dancers (P 0.001) during the stop jump task only. Dancers also took longer to reach peak vGRF and jumped three times higher than non-dancers (P 0.001) during the stop jump task. No difference in peak vGRF between groups was displayed for either task.Adolescent dancers demonstrate a transfer of landing technique to non-ballet specific tasks, reflective of the greater jump height and sagittal plane joint excursions. This landing strategy may be associated with the low rate of non-contact ACL injuries in female dancers.

Ischiofemoral impingement syndrome (IFIS) is an unusual cause of hip pain. Certain strenuous sports can cause this impingement, such as dancing. We report the case of an 11-year-old ballet dancer with bilateral IFIS secondary to overtraining and hypertrophy of the quadratus femoris. This syndrome is frequently evoked in the field of orthopedics following hip replacement. Bilateral IFIS is rare and should be sought in the context of an intense sport such as dance when any other cause has been eliminated.

To assess the association between clinical features and magnetic resonance imaging (MRI) findings in posterior ankle impingement syndrome (PAIS) and to compare the prevalence of imaging findings between participants with and without a clinical diagnosis of PAIS.Case-control study.Elite ballet and sport.Eighty-two male (54%) and female participants comprising ballet dancers (n = 43), cricket fast bowlers (n = 24), and football (soccer) players (n = 15).Clinical: posterior ankle pain on body chart, passive plantarflexion pain provocation test. Patient-reported outcome measures: Oslo Sports Trauma Research Center Overuse Injury Questionnaire, Foot and Ankle Ability Measure Sports subscale.Imaging findings including posterior ankle bone marrow edema, os trigonum (± bone marrow edema, and increased signal at synchondrosis), Stieda process (± bone marrow edema), talocrural and subtalar joint effusion-synovitis size, flexor hallucis longus tendinopathy, and tenosynovitis identified as present or absent on 3.0-Tesla MRI.Imaging findings were not associated with posterior ankle pain or a positive ankle plantarflexion pain provocation test. Imaging findings were not associated with patient-reported outcome measures. Imaging findings did not differ between PAIS-positive and PAIS-negative groups. Os trigonum and Stieda process were prevalent despite clinical status.The lack of association between imaging findings and clinical features questions the role of imaging in PAIS. Clinicians should rely primarily on clinical assessment in the diagnosis and management of patients with PAIS.

Ballet training includes exercises of high and moderate intensities, which require breathing control for a good performance. This study describes the thoracoabdominal motion of professional dancers and compares the breathing patterns between professional dancers and non-dancers. Participants of this study were four male and four female (30.33 ± 4.64 years) professional dancers and four male and four female (22.75 ± 1.49 years) non-dancers. The participants executed two breathing manoeuvres while sitting motionless: quiet breathing (QB) and vital capacity (VC). The 3D coordinates of 32 retro-reflective markers positioned on the trunk were used to calculate the volume of the superior thorax, inferior thorax and abdomen. Principal component analysis was applied in the volume variation of each trunk compartment to search for dominant independent variables in a breathing motion pattern. The correlation coefficient was calculated to verify the coordination between the compartments during the breathing manoeuvres. A predominance of the superior thorax or abdomen movement was found in both groups. The professional ballet dancers have an efficient breathing pattern and maintain the same breathing pattern in QB and VC manoeuvres. On the other hand, the non-dancers group showed relevant changes of the breathing pattern to respond to a greater breathing effort, like in VC.

The ability to jump high with precision is an important component of the ballet dancer's technique. The aim of this study was to evaluate the effect of a modified ballet class on strength and jumping ability in high level female dancers. Seventeen female ballet students were divided into two groups, experimental and control, and tested before and after an 8-week, 2 times/week intervention for peak torque of knee extensors and flexors at 60°and 180°, and jumping ability (squat jump, countermovement jump, countermovement with arm swing jump, sauté in first position, and sauté in first position with port de bras). Statistical analysis was performed using Analysis of Variance (Anova 2x2) with repeated measure of factor time (pre and post). T-test with Bonferroni adjustment was used to assess any differences between groups. The experimental group showed improvement in height (7.7%), takeoff velocity (4.0%), and power (5.1%) of the squat jump. In addition, increases were revealed in peak (60°, 11.9%; 180°, 7.8%) and relative peak torque (60°, 13.2%; 180°, 9.2%) of the right knee flexors. Moreover, enhancements of the knee flexor-extensor strength ratio in both angular velocities were found (60°, 10.4%; 180°, 9.7%). These outcomes suggest that the proposed program could help ballet dancers improve the height of their vertical jumps and leg strength.

The present study addressed whether motor memory acquired earlier in life through specific training can be maintained through later life with further training. To this end, the present study focused on the training effect of a specific ballet practice and investigated the spinally mediated stretch reflex responses of the soleus muscle in ballet dancers of upper‐middle to old age (60.6 ± 5.4 years old) with experience levels of 28.4 ± 7.4 years (“older ballet” group). Comparisons were conducted with a group of young ballet dancers (“young ballet” group) and groups of both young and older individuals without weekly participation in physical activities (“young sedentary” and “older sedentary” groups). The results revealed natural age‐dependent changes, with reflex responses being larger in older sedentary than in young sedentary individuals. A training‐induced effect was also observed, with responses being smaller in ballet dancers than in sedentary groups of the same age. Furthermore, the responses were surprisingly smaller in the older ballet dancers than in the young sedentary group, at an equivalent level to that of the young ballet dancers. The influence of training, therefore, overcame the natural age‐dependent changes. On the other hand, the onset latencies of the responses showed a solely age‐dependent trend. Taken together, the present is the first to demonstrate that the motor memories in the spinal cord acquired through specific ballet training earlier in life can be maintained and carried forward in later life through further weekly participation in the same training., With the knowledge that human motor system undergoes functional changes after participation in specific motor training, the present study first demonstrated that the motor memories in the spinal cord acquired through participation in specific ballet training earlier in life can be maintained and carried forward in later life through further weekly participation in the training.

Dancers are highly trained athletes who are at significant risk of injury due to the repetitive nature of their movement patterns. Most ballet injuries result from overuse and occur in the lower limbs. Therefore, the behavior of the lower limbs during a basic ballet movement should be studied in order to identify and subsequently correct mechanical factors that may contribute to injuries. This study analyzed a cou-de-pied derrière with demi-plié to piqué arabesque gesture executed by 18 ballet dancers identified in two groups: experienced dancers (EDs) and beginner dancers (BDs). Kinematic, baropodometric, and electromyographic analyses enabled the observation of differences between these study groups with regard to joint angles, velocities, foot pressure behavior, and muscle activation during execution of the gesture. Experienced dancers reached greater hip and lumbar spine hyperextension and demonstrated less forward torso flexion, which enables better execution of the gesture compared to BDs. The highest foot pressure in both groups was found in the first metatarsal, with a tendency toward the great toe. In terms of muscular activation, BDs exhibited lower electrical activity than EDs. It is concluded that: 1. ankle and knee angles in demi-plié are not defined by dancers' expertise; 2. the faster the leg is raised during piqué-arabesque the better the gesture; 3. special attention to the metatarsal heads is required due to the high pressures found in this study; and 4. activation of different muscle groups depends on the complexity of the gesture and dancer's expertise.

Excessive forces and/or loading rates during landing may place ballet dancers at risk for overuse injury. The ability to estimate and monitor the landing forces of ballet dancers could help to improve injury prevention and rehabilitation; however, force platforms are not conducive to testing outside of a laboratory. Fortunately, it may be possible to indirectly assess landing forces via a wearable accelerometer. The purposes of this study were to examine the relationship between impact accelerations, recorded via a pelvis-worn accelerometer, and the peak forces and loading rates during performance of a common ballet manoeuvre, and to examine if a wearable accelerometer is sensitive to fatigue-related changes in landing forces. Fifteen ballet dancers continuously performed a ballet manoeuvre until self-determined exhaustion while impact accelerations and landing forces were simultaneously recorded using an accelerometer and force platforms. We observed very strong, positive relationships between the impact accelerations and the peak forces and loading rates during the landings. In addition, the changes in impact accelerations with fatigue paralleled the changes in the peak forces and loading rates. As a result, it appears that a wearable accelerometer could be used to estimate and monitor landing forces in ballet dancers.

Ballet dancers have finite careers due to the demands placed upon their bodies throughout years of training, study, and performance. The average age a dancer retires is 34 due to persistent stress on their joints and injuries due to mechanical overload or overuse. Proper form is crucial to prevent injury. The aim of this study was to establish benchmarks for normal movement patterns among professional dancers. Ten professional ballerinas were studied. Reflective markers were placed on the pelvis, left and right anterior superior iliac spine (ASIS), and posterior iliac spine (PSIS) to evaluate motion during Barre movements: plié, grand battement, and développé. Pelvis flexion/extension, mediolateral rotation, and torsion were analyzed. These motions test different skills. The plié is a controlled coordinated motion using both legs. The grand battement and développé both require leg extension, one with a quick motion that creates momentum and one using controlled motion that requires strength. Each requires core and pelvis stability to perform accurately and with less injury. Dancers' motions were consistent. Maximum pelvis range of motion for the plié, grand battement, and développé were 8.0, 42, and 50 deg, respectively. This represents usable benchmarks with which other dancers may be compared, for example, those who are at different levels of training, injured, predisposed to injury, or recovering from injury. Early recognition of pathologic movement patterns could benefit professional and amateur dancers by helping to prevent injuries, and potentially improve the quality and length of their careers.

Blanco, P, Nimphius, S, Seitz, LB, Spiteri, T, and Haff, GG. Countermovement jump and drop jump performances are related to grand jeté leap performance in dancers with different skill levels. J Strength Cond Res 35(12): 3386-3393, 2021-Thirty-five classical ballet dancers were chosen to investigate relationships between the grand jeté leap, countermovement jump (CMJ), and drop jump (DJ) and establish whether the magnitude of the relationship between these tests differed across 3 skill levels. Subjects (male: n = 11 and female: n = 24) were divided into 3 groups: novice (n = 12; age: 16.6 ± 1.5 years; height: 1.7 ± 0.1 m; body mass: 58.0 ± 13.0 kg), semiprofessional (n = 13; age: 20.0 ± 1.6 years; height: 1.7 ± 0.1 m; body mass: 64.1 ± 10.5 kg), and professional (n = 10; age: 23.8 ± 3.5 years; height: 1.8 ± 1.2 m; body mass: 63.3 ± 14.7 kg). Grand jeté leap height, followed by CMJ and DJ vertical displacement, was assessed. Significant relationships were found between the grand jeté, CMJ (r = 0.77, p = 0.001) and DJ (r = 0.76, p = 0.001). After a Fisher's r-z transformation, professional dancers and novice dancers showed greater r-value differences in CMJ (r2 - r1 = 0.27) compared with novice (r2 - r1 = 0.17) and semiprofessional dancers (r2 - r1 = 0.11), indicating larger strength of CMJ to grand jeté relationship in professionals. The grand jeté leap showed large to very large correlations with CMJ and DJ within groups. These common performance tests were determined to be practical and efficient methods for assessing the jumping ability of dancers. As dance skill increased, larger correlations were observed, suggesting that dancers with superior ballet skills may be more likely to use their underpinning physical capacities to jump higher within the context of ballet-specific jumping.

OBJECTIVE A causal link between ballet, hip pain, and pathology has not been established. Change in ballet dancers' hip pain and cartilage defect scores were investigated over 5 years. DESIGN Longitudinal. SETTING Professional ballet company. PARTICIPANTS Twenty-one professional ballet dancers (52% men). INDEPENDENT VARIABLES Baseline and follow-up Copenhagen Hip and Groin Outcome Score (HAGOS-pain subscale); incidence of hip-related pain and levels of dance participation collected daily over 5 years; bony morphology measured on baseline 3T magnetic resonance imaging (MRI). MAIN OUTCOME MEASURE Change in cartilage defect score on MRI between baseline and 5-year follow-up. RESULTS Cartilage scores did not increase in 19 (90%) dancers. There was one new cartilage defect and one progressed in severity. At follow-up, all 6 dancers with cartilage defects were men. Group HAGOS pain scores were high 97.5 (7.5) and not related to cartilage defects (P = 0.12). Five (83%) dancers with baseline cartilage defects reported HAGOS pain scores

AIMS: Research demonstrates that dancers benefit from reduced injury risk and improved health by engaging in strength training and conditioning (STC). Historic bias within the discipline of dance, however, establishes a long-standing stigma that gains in muscle mass and strength lessen a dancer's aesthetic appearance, and thus many dancers rebuff STC as a supplement to dance training. However, there is growing evidence that dancers and dance educators are beginning to understand the importance of additional resistance training and cardiovascular conditioning. This study explored dancers' perceptions and utilization of STC using a general qualitative approach. METHODS: Twenty-three female collegiate dancers (13 contemporary dancers, 10 ballet dancers, mean age 19.95 x 0.97 yrs) volunteered to participate in this study. The principal investigator conducted individual, semi-structured interviews. RESULTS: Inductive analysis revealed three major themes: 1) evolving body image, 2) motivation, and 3) education. Trustworthiness was established using member checks, peer debriefing, and journaling. This study concluded collegiate dancers utilized STC as a means to enhance the individual's body image. This was driven by a continuum of motivating factors. Although collegiate dancers are utilizing STC, education on STC techniques and practices was minimal. CONCLUSIONS: While further research is needed, results from this study suggest STC could be initiated and promoted in the discipline of dance to further enhance physical fitness and general well-being. Dancers and dance instructors should receive education about the importance of STC within dance training as well as how to safely implement STC exercise into training regimens.

BACKGROUND: Data documenting BMD in pre-professional adolescent ballet dancers is limited. This cross-sectional study assesses hone mineral density (BMD) in young adolescent elite ballet dancers and compares BMD values between males and females (with and without normal menarche) and body composition between dancers with and without low Z-score. METHODS: Cross-sectional study of third year ballet students (female=23; male=15; mean age 14.7 years; SD: 0.5) of The Royal Ballet School of Antwerp (Belgium) training 22 hours a week. They completed questionnaires and underwent dual energy X-ray absorptiometry (DXA) to measure BMD and body composition. Each female participant completed questionnaires assessing menstrual status. RESULTS: DXA revealed that 12 out of 38 (32%) of the dancers had Z-score

Ballet training has been reported to positively influence balance ability. It is not entirely clear how improved balance ability manifests under standing conditions with different demands on postural control. The aim of the study was to compare balance of ballet dancers and non-dancers in a unipedal stance under different conditions. Twenty-five professional ballet dancers and twenty-five controls completed four unipedal standing balance tests: firm surface with eyes open and closed; foam mat surface with eyes open; and firm surface with eyes open immediately after performing ten 360° whole-body turns. The centre of pressure (COP) data were obtained with a force platform and the direction-specific standard deviations, velocities, and sample entropy of the COP displacement were computed. A three-way analysis of variance was used to compare groups, genders, and conditions. For standing immediately after performing ten turns, the postural sway parameters were significantly larger in the control group compared to the ballet dancers in both men and women. In this stance condition the values of postural sway and COP velocities in the control group were larger in the men compared to the women. For both genders in the control group all postural sway and COP velocity parameters were larger in standing with eyes closed and standing after performing 10 turns compared to standing with eyes open on both firm and foam surface. In the ballet dancers all COP velocity parameters were larger in standing with eyes closed compared to all other conditions. The results from the present study indicate that professional ballet dancers do not have a better general balance ability than untrained subjects.

Physical training has frequently been indicated for ballet dancers to strengthen their trunk muscles, improve their performance, and avoid injuries. The current authors hypothesized that these dancers could benefit from Pilates exercises to stabilize their trunk muscles and improve joint stability and neuromuscular efficiency (NME). Our study aimed at evaluating the NME and isometric strength of the internal oblique (IO) and multifidus (MU) muscles in a healthy 24-year-old classical ballerina before and after an 8-week Pilates exercise intervention. The muscles were tested with electromyography (EMG) and a dynamometer, and the resulting torque and EMG values were used to calculate the NME. Based on the results, the Pilates exercises could improve the NME of the muscles tested, since the torque increased and the EMG activity decreased after the intervention.

AIM To investigate hip magnetic resonance imaging (MRI) findings in asymptomatic professional male rugby players and male ballet dancers compared to age-matched controls. MATERIALS AND METHODS After ethics committee approval and consent from participants, 11 professional rugby players, 10 professional ballet dancers, and 10 controls completed activity and symptom questionnaires and underwent 3 T MRI of their self-declared dominant hip. Each scan was independently scored by two musculoskeletal radiologists for multiple features, including: joint morphology, acetabular labrum appearance, cartilage loss, and capsular thickness. Clinical and MRI features were assessed for variance by group using one-way analysis of variance (ANOVA) tests and Tukey post-hoc pairwise comparison of means. RESULTS Labral tear prevalence was 87% with no significant difference between groups (p>0.05). Rates of paralabral cysts were significantly higher in ballet dancers (50%), compared to rugby players (0%) and controls (10%; p=0.01). Acetabular cartilage loss was present in 54% with no significant differences between groups. Superior capsular thickness was significantly greater in ballet dancers (5.3 mm) compared to rugby players (3.8 mm) and controls (3.8 mm; p=0.03). CONCLUSION Despite the difference in type of activity between groups, there were equally high rates of labral tears and acetabular cartilage loss, questioning the role that sport plays in the development of these findings and their relationship to symptoms. The focally increased superior capsular thickness in ballet dancers may be an adaptive response to extreme ranges of movement.

To progress to a high level in classical ballet, en pointe is a requirement. The aim of this literature review was to evaluate the available evidence relating to readiness for dancing en pointe, including injury rates in the adolescent dancer population, screening tools, and pre-pointe training methods.It has been emphasized that young dancers are a demographic at increased risk of injury, especially as they progress through the growth spurt and increase their training hours. Dancers are commonly screened at the pre-pointe level, but unfortunately the majority of evidence resulting from this process, as reported in the literature, is subjective in nature. Hence, there is large variance regarding an appropriate time or level to commence en pointe training,and it remains unclear what dance teachers should be looking for in making this decision. A further paucity of evidence is demonstrated with regard to pre-pointe training protocols or instruction; in this review, no published literature was found on the topic. As such, there is a clear need for further study of pre-pointe screening and en pointe training protocols. Refereed/Peer-reviewed

Background: The prevalence of anorexia nervosa among males is increasing but few data are available in the literature. This cross sectional study aims to evaluate resting energy expenditure (REE) and phase angle as a marker of qualitative changes of fat free mass (FFM) in three leanness groups as compared with control subjects. Methods: 17 anorectic (AN) males, 15 constitutionally lean (CL) individuals, 12 ballet dancers (DC), and 18 control (CTR) subjects were evaluated. REE was measured by indirect calorimetry (V max29- Sensormedics), and body composition was evaluated by bioimpedance analysis (BIA) at 50 kHz (DS Medica). Phase angle (a bioimpedance variable related to nutritional status) was used to evaluate differences in FFM characteristics between these three types of leanness. Results: REE, adjusted for FFM and fat mass (FM), were significantly higher in CL and lower in AN individuals (1783 &plusmn, 47 vs. 1291 &plusmn, 58 kcal, p &lt, 0.05) compared to the other groups. Body composition was similar in AN and CL whereas dancers had the highest FFM (58.9 &plusmn, 4.8 kg, p &lt, 0.05), anorectic males showed the lowest phase angle (5.8 &plusmn, 1.2 degrees vs. other groups, p &lt, 0.05) and dancers the highest phase angle (7.9 &plusmn, 0.7 degree vs. other group, p &lt, 0.05). Conclusions: Our findings confirm that phase angle could be a useful marker of qualitative changes, above all in the field of sport activities. On the other hand, there is the need to further evaluate the relationship between resting energy expenditure, body composition and endocrine status in different conditions of physical activity and dietary intake.

The purpose of this study is to compare the effects of stretching methods on flexibility, muscle activation, and pressure pain threshold in ballet dancers, and to suggest an effective stretching method.Thirty-three ballet dancers were randomized to the static stretching group (n = 11), muscle energy technique stretching group (n = 11), and vibration-assisted stretching group (n = 11). The angle of hip joint extension in arabesque, activation of the rectus femoris in devéloppé, and pressure pain threshold on the rectus femoris in the sitting position were measured to compare the effects of the different stretching methods. Paired t-test was used to compare the pre and post-intervention findings within each group and one-way analysis of variance to compare the difference in the amount of changes among the groups.The hip joint extension angles increased in all stretching methods (p 0.05); however, vibration-assisted stretching and muscle energy technique stretching were more effective than static stretching (p 0.05). The activation of the rectus femoris decreased in all groups (p 0.05); however the muscle energy technique stretching group and vibration-assisted stretching group showed a significant decrease in muscle activation compared with the static stretching group (p 0.05). The pressure pain threshold significantly improved only in the static stretching group (p 0.05); and vibration-assisted stretching group (p 0.05).Compared with static stretching and muscle energy technique stretching, vibration-assisted stretching is a beneficial method for improving flexibility, muscle activation, and pressure pain threshold in ballet dancers.

We aimed to investigate joint coordination of lower limbs in dancers during tiptoe standing and the relationship between joint coordination and muscle coactivation. Seven female ballet dancers performed tiptoe standing with six leg positions (fi e classical dance positions and one modern dance position) for 10 s. The kinematic data of the metatarsophalangeal (MP), ankle, knee, and hip joints was collected, and surface electromyography (EMG) of over 13 lower limb muscles was conducted. Principal component analysis was performed to determine joint coordination. MP–ankle and ankle–knee had in-phase coordination, whereas knee–hip showed anti-phase coordination in the sagittal plane. In addition, most EMG–EMG coherence around the MP and ankle joints was significant up to 50 Hz when these two joints swayed with in-phase. This suggests that different joint coordination patterns are associated with neural processing related to different muscle coactivation patterns. In conclusion, ballet dancers showed in-phase coordination from the MP to knee joints, which was associated with muscle coactivation to a higher frequency domain (up to 50 Hz) in comparison with anti-phase coordination.

This study describes trends in mean standing functional turnout angles measured on a floor protractor (FP) and the Functional Footprint(®) rotational instrument (RI) during routine clinical screens. Twenty-three professional ballet dancers, 26 collegiate modern students, and 46 ballet academy dancers participated in the study. All dancers demonstrated greater total turnout on the FP compared to the RI (p < 0.001), and the collegiate dancers had significantly smaller total turnout angles compared to both of the other groups (p < 0.001). A significant interaction between measurement method and training group (p = 0.047) on lower extremity asymmetry indicated that only in professionals left turnout angle was greater than right turnout angle on the RI (4.30° ± 6.64°) but not on the FP (0.17° ± 4.57°). It is concluded that turnout can be measured using either the FP or the RI measurement method, with recognition that FP measurements will be an average of 10° greater than those on the RI. Lower extremity asymmetries in turnout angles may be better detected on the RI than the FP.

Aimed to investigate whether young male and female dancers have different patterns of association between static and dynamic postural balance (PB), 60 dancers from the Australian Ballet School (14–19 years old) were tested for static and dynamic PB with head and lumbar accelerometers. Monotonic relationships between static and dynamic PB were found in head movements among young female dancers in all three directions, but were found for young male dancers in the mediolateral (ML) and anteroposterior (AP) directions only. In lumbar movements, monotonic relationships were found for young female dancers in the AP direction only. Comparing head with lumbar movements in static PB, young male dancers demonstrated monotonic relationships between head and lumbar movements in all 3 directions; however, young female dancers demonstrated monotonic relationships in the AP direction only. In the dynamic measurements, both male and female dancers demonstrated monotonic relationships between head and lumbar movements for all parameters measured in the ML and vertical directions (p < .05). In conclusions, among female dancers static PB ability is correlated with their dynamic ability, whereas among male dancers, no relationship between the static and dynamic PB in the AP direction exists. Male dancers showed head and lumbar coordination in the static PB movement, but both genders manifested no head and lumbar coordination in the AP direction measured for dynamic PB.