The Impact of Dance-Specific Neuromuscular Conditioning and Injury Prevention Training on Motor Control, Stability, Balance, Function and Injury in Professional Ballet Dancers: A Mixed-Methods Quasi-Experimental Study

Health Problems of Professional Ballet Dancers: an Analysis of 1627 Weekly Self-Reports on Injuries, Illnesses and Mental Health Problems During One Season

BACKGROUND

Several studies have investigated injuries of (pre-)professional ballet dancers, however most used a medical-attention and/or time-loss definition and did not analyse the prevalence of all health problems. The aim was to analyse the frequency and characteristics of all self-reported physical and mental health complaints (i.e. injuries, illnesses and mental health problems) of professional ballet dancers during one season.

METHODS

Three professional ballet companies were prospectively monitored weekly during one season with the Performing artist and Athlete Health Monitor (PAHM). Numerical rating scales (ranging 0-10) were used for severity of musculoskeletal pain, all health problems and impairment of the ability to dance at full potential in the previous seven days. If dancers rated the severity of their health problems or their impairment greater than 0, they were asked to answer specific questions on the characteristics of each health problem.

RESULTS

Over a period of 44 weeks, 57 dancers (57.9% female) filled in 1627 weekly reports (response rate of 64.9%), in which 1020 (62.7%) health problem were registered. The dancers reported musculoskeletal pain in 82.2% of the weeks. They felt that their ability to dance at their full potential was affected due to a health problem in about every second week (52.6%) or on at least 29.1% of the days documented in the weekly reports. Almost all dancers (96.5%) reported at least one injury, almost two thirds (64.9%) an illness and more than a quarter (28.1%) a mental health problem. On average, every dancer reported 5.6 health problems during the season. Most of the 320 health problems were injuries (73.1%), 16.9% illnesses and 10.0% mental health problems. Injuries affected mainly ankle, thigh, foot, and lower back and were mostly incurred during rehearsal (41.6%) or training (26.1%). The most frequent subjective reasons of injury were "too much workload" (35.3%), "tiredness/exhaustion" (n = 22.4%) and "stress/overload/insufficient regeneration" (n = 21.6%).

CONCLUSION

Preventive interventions are urgently required to reduce the prevalence of health problems and especially injuries of professional dancers. Injury prevention measures should regard the balance of the load capacity of professional dancers and the workload in training, rehearsals and performances.

Strength and conditioning in dance: A systematic review and meta-analysis

To assess the evidence for the effect of strength and conditioning on physical qualities and aesthetic competence in dance populations, three electronic databases (PubMed, Scopus, SPORTDiscus) were searched (until September 2022) for studies that met the following criteria: (i) dancers aged >16 years; (ii) structured strength and conditioning intervention; and (iii) with physical qualities and aesthetic competence as outcome measures. Methodological quality and risk of bias of the included studies were assessed through the systematic review tool "QualSyst". Meta-analyses of effect sizes (Hedges' g) with forest plots explored the effects of the strength and conditioning interventions. Thirty-six studies met the inclusion criteria and were included in this review. Meta-analysis indicated strength and conditioning significantly (p < 0.05) improved lower body power (g = 0.90, 95% CI: 0.53-1.27), upper body strength (g = 0.98, 95% CI: 0.39-1.57), lower body strength (g = 1.59, 95% CI: 0.97-2.22), and flexibility (g = 0.86, 95% CI: 0.05-1.66). Strength and conditioning interventions were found to be effective at improving physical qualities in dancers, recommending their participation in additional sessions to enhance overall fitness and ultimately dance performance. It is recommended that future strength and conditioning intervention research should include sample size calculations, with participants recruited from a specific dance genre and skill level in order to evaluate how strength and conditioning influences dance performance.

Effect of Conservative Interventions for Musculoskeletal Disorders in Preprofessional and Professional Dancers: A Systematic Review

Background

Preprofessional and professional dancers are among the athletes who sustain the most musculoskeletal disorders. In recent years, conservative treatment and preventive measures have been investigated in this population. However, no systematic review regarding their effectiveness has been conducted.

Hypothesis/Purpose

The aim of this systematic review was to locate, appraise and synthesize the available information on conservative interventions currently used for treating and preventing MSK disorders and their effect on pain and function in preprofessional and professional dancers.

Study design

Systematic review.

Methods

A systematic literature search was conducted using PubMed, CINHAL, ERIC, SportDiscus and Psychology and behavioral science collection. Prospective and retrospective cohort studies, as well as randomized and non-randomized controlled trials investigating conservative interventions for musculoskeletal disorders in preprofessional and professional dancers were included in this study. The main outcome measures included pain intensity, function, and performance. All included studies were evaluated for risk of bias using the Downs and Black checklist.

Results

Eight studies were included in the review. These studies included ballet and contemporary dancers, as well as professional and preprofessional dancers. In total, the studies included 312 dancers, 108 male and 204 female. Studies had a risk of bias that ranged from poor (8/28) to good (21/28) on the Downs and Black checklist. The conservative interventions used included customized toe caps, dry-needling, motor imagery, and strength and conditioning programs. The use of customized toe caps, motor imagery and strength and conditioning programs had promising results regarding pain and function in dancers.

Conclusion

In order to reach a solid conclusion, more quality studies are needed. The addition of control groups to studies, as well as multimodal interventions should be considered.

Level of Evidence

I.

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.

Does 8 Weeks of Integrated Functional Core and Plyometric Training Improve Postural Control Performance in Young Rhythmic Gymnasts?

It has been suggested that core stability and plyometric training (CPT) can enhance athletes' postural control. Nevertheless, the effects of an integrated core and plyometric training program on rhythmic gymnastics (RG) performance are unclear. This study aimed to evaluate the effects of an integrated functional CPT program on young rhythmics gymnasts' postural performance. A sample of 44 young female rhythmic gymnasts from a competitive team (age = 10.5 ± 1.8 years) participated in the study. The subjects were randomly divided into a control group and an experimental group. Pre- and posttest design was used. Postural control was assessed using single-leg stance tests and RG-specific balances over a force platform and evaluated by expert RG judges. The experimental group (n = 23) completed an 8-week functional CPT program based on RG technical requirements. Meanwhile, the control group (n = 21) received their usual training sessions. A mixed model of analysis of variance was applied to evaluate the effects of an intrasubject factor and an intersubject factor on each of the dependent variables. After 8 weeks, the experimental group obtained significant better results in some variables of the right support leg with eyes open and left support leg with eyes open single-leg support (p < .01), improvements were also found in some specific RG balances: Arabesque measured on the force platform (p < .01) and the side leg with help balance scored by the judges (p < .01). In conclusion, an integrated functional CPT program improved postural control in young rhythmic gymnasts. Coaches should consider using this CPT to improve RG performance.

The Effect of Eight-Week Functional Core Training on Core Stability in Young Rhythmic Gymnasts: A Randomized Clinical Trial

It is suggested that core stability (CS) might improve rhythmic gymnasts’ performance. Nevertheless, the effect of core stability training (CST) in CS performance is not clear. Purpose: Evaluating the effect of an eight-week functional CST on young rhythmics gymnasts’ CS performance. Method: A sample of 45 young female rhythmic gymnasts from a competitive team (age = 10.5 ± 1.8 years, height = 144.1 ± 10.6 cm, weight 38.2 ± 8.9 kg, peak height velocity (PHV) = 12.2 ± 0.6 years) participated in the study. The participants were randomly allocated into the control group (CG) and experimental group (EG) and completed pre-tests and post-tests of specific CS tests using a pressure biofeedback unit (PBU). The CS was assessed by the bent knee fall out (BKFO), the active straight leg raise (ASLR) tests and the pelvic tilt test, all performed on the right and left sides. The EG (n = 23) performed an eight-week functional CST program based on rhythmic gymnastics (RG) technical requirements added to the traditional RG training sessions. Meanwhile, the CG (n = 22) received the traditional RG training sessions. Results: Mixed model analysis showed non-significant interaction effects; however, the ANOVA omnibus test showed a time effect (p < 0.05) in right BKFO (F1,42 = 4.60; p = 0.038) and both pelvic tilt tests (right F1,42 = 22.01, p < 0.001; left F1,42 = 19.13, p < 0.001). There were non-significant interaction effects. The fixed effects estimated parameters for right BKFO showed that both groups had less pressure variation after intervention compared with pre-intervention (β = −1.85 mmHg, 95%CI = [−3.54 to −0.16], t42 = −2.14, p = 0.038). Furthermore, the left pelvic tilt (β = 37.0 s, 95%CI = [20.4 to 53.6], t42 = 4.37, p < 0.001) improved 8.9 s more than the right pelvic tilt (β = 28.1 s, 95%CI = [16.3 to 39.8], t42 = 4.69, p < 0.001) considering both groups together. Conclusions: Adding a functional CST to regular training showed a trend in improving the performance of CS-related variables, which could help improve RG-specific performance. Coaches working with rhythmic gymnasts should consider adding a functional CST to regular training to improve CS performance leading to increased specific RG performance.