The Effectiveness of Dance Interventions on Psychological and Cognitive Health Outcomes Compared with Other Forms of Physical Activity: A Systematic Review with Meta-analysis.

BACKGROUND: Physical activity is known to improve psychological and cognitive outcomes. Learning dance sequences may challenge cognition, partnered or group dance may benefit social interactions, and the artistic aspect may improve psychological wellbeing. Dance is an equally effective form of physical activity compared with other structured physical activities to improve physical health, but it is unclear how effective dance could be for psychological and cognitive outcome measures. OBJECTIVE: To systematically review the literature on the effectiveness of structured dance interventions, compared with structured exercise programmes, on psychological and cognitive outcomes across the lifespan. METHODS: Eight databases were searched from earliest records to July 2022. Studies investigating a dance intervention lasting ≥ 4 weeks, including psychological and/or cognitive health outcomes, and having a structured exercise comparison group were included. Screening and data extraction were performed by two independent reviewers at all stages. All reviewer disagreements were resolved by the primary author. Where appropriate, meta-analysis was performed, or an effect size estimate generated. RESULTS: Of 21,737 records identified, 27 studies met the inclusion criteria. Total sample size of included studies was 1392 (944 females, 418 males, 30 unreported). Dance was equally as effective as other physical activity interventions in improving quality of life for people with Parkinson's disease [mean difference 3.09; 95% confidence interval (CI) - 2.13 to 8.30; p = 0.25], reducing anxiety (standardised mean difference 2.26; 95% CI - 2.37 to 6.90; p = 0.34), and improving depressive symptoms (standardised mean difference 0.78; 95% CI - 0.92 to 2.48; p = 0.37). Preliminary evidence found dance to be superior to other physical activity interventions to improve motivation, aspects of memory, and social cognition and to reduce distress. Preliminary evidence found dance to be inferior to other physical activity interventions to improve stress, self-efficacy and language fluency. CONCLUSION: Undertaking structured dance of any genre is generally equally and occasionally more effective than other types of structured exercise for improving a range of psychological and cognitive outcomes. TRIAL REGISTRATION: PROSPERO: CRD42018099637.

The Biomechanics Research and Innovation Challenge: Development, Implementation, Uptake, and Reflections on the Inaugural Program.

Biomechanics as a discipline is ideally placed to increase awareness and participation of girls and women in science, technology, engineering, and mathematics. A nationwide Biomechanics and Research Innovation Challenge (BRInC) centered on mentoring and role modeling was developed to engage high school girls (mentees) and early-mid-career women (mentors) in the field of biomechanics through the completion of a 100-day research and/or innovation project. This manuscript describes the development, implementation, and uptake of the inaugural BRInC program and synthesizes the research and innovation projects undertaken, providing a framework for adoption of this program within the global biomechanics community. Eighty-seven high school girls in years 9 and 10 (age range: 14-16 y) were mentored in teams (n = 17) by women in biomechanics (n = 24). Using a design thinking approach, teams generated solutions to biomechanics-based problem(s)/research question(s). Eight key reflections on program strengths, as well as areas for improvement and planned changes for future iterations of the BRInC program, are outlined. These key reflections highlight the innovation, impact, and scalability of the program; the importance of a program framework and effective communication tools; and implementation of strategies to sustain the program as well as the importance of diversity and building a sense of community.

Dance for Chronic Pain Conditions: A Systematic Review.

OBJECTIVES: Globally, 20-25% of people will experience chronic pain in their lifetimes. Dance is a physical activity with psychosocial benefits that might positively impact pain. This review aimed to investigate the effect of dance interventions on the experience of pain by quantitative measures and qualitative themes. METHODS: Seven major databases were searched from inception to January 2021. Two independent reviewers screened articles at each stage. Qualitative and quantitative studies were included if the dance interventions lasted more than 6 weeks, participants reported pain of duration longer than 3 months, and pain was an outcome of the study. All articles were critically appraised with appropriate Joanna Briggs Institute tools, and data were collated through the use of results-based convergent synthesis. RESULTS: From 23,628 articles, 34 full papers were included, with a total of 1,254 participants (75.2% female). Studies predominantly investigated individuals with fibromyalgia (26%) and generalized chronic pain (14%), with aerobic dance (20.7%) and Biodanza (20.7%) being the most common dance genres investigated. Overall, 74% of studies noted either reduced pain through quantitative pain measures or qualitative themes of improved pain experience (88% for chronic primary pain and 80% for chronic secondary musculoskeletal pain). DISCUSSION: There were positive effects of dance on chronic primary and secondary musculoskeletal pain across diverse populations. A variety of study designs and interventions noted improved pain measures and themes around pain coping and acceptance, with all dance therapies showing improvements, particularly when performed for 60-150 minutes' duration weekly. Dance should be considered as an effective adjunct in the management of chronic pain.

Is there an association between high-speed running biomechanics and hamstring strain injury? A systematic review.

Despite increased awareness of the multifactorial nature of Hamstring Strain Injury (HSI), the role of running biomechanics remains unclear. The aim of this systematic review was to investigate whether an association exists between running biomechanics and HSI. Five databases were searched from inception to January 2021. Eligibility criteria included epidemiological studies that provide data on running biomechanics in athletes who have sustained a HSI (retrospectively or prospectively) and compared to control data. Searches yielded 4,798 articles. Twelve met the selection criteria. Biomechanical analysis differed considerably across studies, thus meta-analyses was not possible. Studies largely found either no differences or contradicting findings between running biomechanics of athletes who have sustained a HSI (retrospectively or prospectively) and controls, with the exception of lateral trunk kinematics and horizontal propulsive forces. It is important to note some concern regarding the quality of included studies, particularly sample size, increasing the risk of bias associated with results. Further research utilising validated methods of biomechanical analysis, is needed to determine if an association exists between running biomechanics and HSI. Until then, definitive conclusions cannot be drawn as to whether specific biomechanical interventions should be included in injury prevention and/or rehabilitation programmes.

Excellent reliability of toe strength measurements in children aged ten to twelve years achieved with a novel fixed dynamometer.

BACKGROUND: Stronger toe flexor muscles improve performance outcomes in children, including balance, sprinting, jumping and side stepping. Toe flexor strength (TFS) is recommended as part of the clinical assessment of foot function in children. Fixed dynamometry, rather than handheld, is the gold standard of measurement; however, it can be prohibitively costly. No fixed dynamometer reliability studies on toe flexion have been conducted in children to date. RESEARCH QUESTIONS: Does the novel fixed hand-held dynamometer (HHD) protocol provide reliable intra-rater and test-retest measurements of toe flexor strength in children aged 10 to 12? METHODS: Two trials were recorded from 14 healthy children (10-12 years), 7-14 days apart by the same rater. A Lafayette HHD (model 01163) measured peak force. The HHD was secured in a mobile custom mould below a step with a strap, which secured the foot of the participant. The receptor pads of the HHD were level with the upper surface of the step, maintaining neutral toe joints at rest. The participant was seated on an adjustable stool to ensure the hip, knee and ankle were each at 90° flexion, with the testing foot flat on the upper surface of the step. The averages of three maximal five second efforts were used for data analysis using a two-way mixed effects model with repeated measures ANOVA (intraclass correlation coefficient ICC 3,3). Standard error of measurement (SEM) was calculated to determine the absolute between trial variability. RESULTS: The novel fixed HHD protocol provided excellent test-retest reliability with small measurement error for hallux (ICC 3,3 = 0.93, 95 % CI 0.78-0.98, SEM = 4.31 N) and lesser toe flexor strength testing (ICC 3,3 = 0.96, 95 % CI 0.87-0.99, SEM = 1.86 N). SIGNIFICANCE: The fixed HHD protocol described in this study has excellent reliability for the test-retest evaluation of children's toe flexor strength.

The evidence for improving balance by strengthening the toe flexor muscles: A systematic review.

BACKGROUND: Poor postural balance in the upright position is strongly correlated to morbidities, such as falls in older adult populations and to lower limb injuries in the younger populations. Good postural balance depends on muscular strength and the integration of neurological and muscular feedback mechanisms throughout the body. Since the interface with the ground is the plantar surface of each foot, an improved understanding of the role of foot muscles in postural balance is warranted. RESEARCH QUESTION: Does improved toe flexor strength result in better postural balance, across the lifespan? METHODS: A systematic review was conducted of papers from 1900 to 2019 inclusive, from five databases. Inclusion and exclusion criteria were established prior to selection. Inclusion criteria were: observational and longitudinal studies, healthy subjects, at least one balance and one toe flexor strength test conducted. Exclusion criteria were: subjects with a pathology/disability, case study, systematic or literature review. Two examiners assessed a study's suitability for inclusion in this review, based on the above criteria. Study quality was assessed using the Critical Appraisal Skills Program Tools. The type of studies and methodological heterogeneity precluded the feasibility of conducting a meta-analysis. RESULTS: Nine studies were included. In each study, participants were over sixty years of age, and over 73 % of them were female. No study was found for a younger population group. There were seven cross-sectional studies, two randomized control trials and there was one case-control study. All studies provided evidence of directly proportional, clinically significant correlations between toe flexor strength and postural balance. SIGNIFICANCE: Toe flexor strength contributes to improved postural balance for people over the age of 60. Research is needed to establish the relationship between foot muscle strength and balance in younger adults and children.

Comparison of lower limb stiffness between male and female dancers and athletes during drop jump landings.

Repetition of jumps in dance and sport training poses a potential injury risk; however, non-contact landing injuries are more common in athletes than dancers. This study aimed to compare the lower limb stiffness characteristics of dancers and athletes during drop landings to investigate possible mechanisms of impact-related injuries. Kinematics and kinetics were recorded as 39 elite modern and ballet dancers (19 men and 20 women) and 40 college-level team sport athletes (20 men and 20 women) performed single-legged drop landings from a 30-cm platform. Vertical leg stiffness and joint stiffness of the hip, knee, and ankle were calculated using a spring-mass model. Stiffness data, joint kinematics, and moments were compared with a group-by-sex 2-way analysis of variance. Multiple linear regression was used to assess the relative contribution of hip and knee and ankle joint stiffness to variance in overall vertical leg stiffness for dancers and athletes. Dancers had lower leg (P < 0.001), knee joint (P = 0.034), and ankle joint stiffness (P = 0.043) than athletes. This was facilitated by lower knee joint moments (P = 0.012) and greater knee (P = 0.029) and ankle joint (P = 0.048) range of motion in dancers. Males had higher leg (P < 0.001) and ankle joint stiffness (P < 0.001) than females. This occurred through lower ankle range of motion (P < 0.001) and greater ankle moment (P = 0.022) compared to females. Male and female dancers demonstrated reduced lower limb stiffness compared to athletes, indicating a more pliable landing technique. Dance training techniques could potentially inform approaches to injury prevention in athletes.

The Effectiveness of Dance Interventions on Physical Health Outcomes Compared to Other Forms of Physical Activity: A Systematic Review and Meta-Analysis.

BACKGROUND: Physical inactivity is one of the key global health challenges as it is associated with adverse effects related to ageing, weight control, physical function, longevity, and quality of life. Dancing is a form of physical activity associated with health benefits across the lifespan, even at amateur levels of participation. However, it is unclear whether dance interventions are equally as effective as other forms of physical activity. OBJECTIVE: The aim was to systematically review the literature on the effectiveness of structured dance interventions, in comparison to structured exercise programmes, on physical health outcome measures. METHODS: Seven databases were searched from earliest records to 4 August 2017. Studies investigating dance interventions lasting > 4 weeks that included physical health outcomes and had a structured exercise comparison group were included in the study. Screening and data extraction were performed by two reviewers, with all disagreements resolved by the primary author. Where appropriate, meta-analysis was performed or an effect size estimate generated. RESULTS: Of 11,434 studies identified, 28 (total sample size 1276 participants) met the inclusion criteria. A variety of dance genres and structured exercise interventions were compared. Meta-analyses showed dance interventions significantly improved body composition, blood biomarkers, and musculoskeletal function. The effect of either intervention on cardiovascular function and self-perceived mobility was equivalent. CONCLUSION: Undertaking structured dance of any genre is equally and occasionally more effective than other types of structured exercise for improving a range of health outcome measures. Health practitioners can recommend structured dance as a safe and effective exercise alternative.

Impact attenuation properties of jazz shoes alter lower limb joint stiffness during jump landings.

OBJECTIVES: To quantify the impact attenuation properties of the jazz shoes, and to investigate the in-vivo effect of four jazz shoe designs on lower limb joint stiffness during a dance-specific jump. DESIGN: Repeated measures. METHODS: A custom-built mechanical shoe tester similar to that used by athletic shoe companies was used to vertically impact the forefoot and heel region of four different jazz shoe designs. Additionally, dancers performed eight sautés in second position in bare feet and the shoe conditions. Force platforms and 3D-motion capture were used to analyse the joint stiffness of the midfoot, ankle, knee and hip during the jump landings. RESULTS: Mechanical testing of the jazz shoes revealed significant differences in impact attenuation characteristics among each of the jazz shoe designs. Gross knee and midfoot joint stiffness were significantly affected by the jazz shoe designs in the dancers' jump landings. CONCLUSIONS: The tested jazz shoe designs altered the impact attenuating capacity of jump landing technique in dancers. The cushioned jazz shoes are recommended particularly for injured dancers to reduce impact on the lower limb. Jazz shoe design should consider the impact attenuation properties of the forefoot region, due to the toe-strike landing technique in dance movement.

1000 Norms Project: protocol of a cross-sectional study cataloging human variation.

BACKGROUND: Clinical decision-making regarding diagnosis and management largely depends on comparison with healthy or 'normal' values. Physiotherapists and researchers therefore need access to robust patient-centred outcome measures and appropriate reference values. However there is a lack of high-quality reference data for many clinical measures. The aim of the 1000 Norms Project is to generate a freely accessible database of musculoskeletal and neurological reference values representative of the healthy population across the lifespan. METHODS/DESIGN: In 2012 the 1000 Norms Project Consortium defined the concept of 'normal', established a sampling strategy and selected measures based on clinical significance, psychometric properties and the need for reference data. Musculoskeletal and neurological items tapping the constructs of dexterity, balance, ambulation, joint range of motion, strength and power, endurance and motor planning will be collected in this cross-sectional study. Standardised questionnaires will evaluate quality of life, physical activity, and musculoskeletal health. Saliva DNA will be analysed for the ACTN3 genotype ('gene for speed'). A volunteer cohort of 1000 participants aged 3 to 100 years will be recruited according to a set of self-reported health criteria. Descriptive statistics will be generated, creating tables of mean values and standard deviations stratified for age and gender. Quantile regression equations will be used to generate age charts and age-specific centile values. DISCUSSION: This project will be a powerful resource to assist physiotherapists and clinicians across all areas of healthcare to diagnose pathology, track disease progression and evaluate treatment response. This reference dataset will also contribute to the development of robust patient-centred clinical trial outcome measures.

Kinematic analysis of sautés in barefoot and shod conditions.

Dancers are exposed to many landings from jumps during class and performance, and repetitive loading has been linked with an increased risk of injury. Little is known about the effect of different dance shoe types on jump landings, and with so many dance shoe designs available to choose from, a thorough exploration is warranted. Dance technique dictates that jump landings be "rolled through the foot," with a toe strike followed by controlled lowering of the ball of the foot and heel. For this study, 3D motion analysis was used to capture the movement of 16 female dancers performing sautés in second position. Lower limb joint kinematics were examined during the landings, both barefoot and in different jazz shoe designs. The results showed that all dancers executed the technique of "rolling through the foot." All jazz shoe designs increased knee and ankle sagittal ROM (p < 0.05) but reduced ankle frontal plane ROM and midfoot ROM in all three planes (p < 0.05). Chorus shoes increased maximum knee flexion by more than 5° during the plié. Jazz shoes restricted midfoot sagittal and transverse plane motion and MPJ sagittal motion compared to barefoot throughout stance phase (p < 0.05). These changes may translate to a reduced capacity to absorb impact or decreased propulsion. Dance jump landings in the jazz shoe designs tested may appear to be heavier due to the greater reliance on knee flexion to absorb impact and less push-off for subsequent jumps.

Impact attenuation during weight bearing activities in barefoot vs. shod conditions: a systematic review.

Although it could be perceived that there is extensive research on the impact attenuation characteristics of shoes, the approach and findings of researchers in this area are varied. This review aimed to clarify the effect of shoes on impact attenuation to the foot and lower leg and was limited to those studies that compared the shoe condition(s) with barefoot. A systematic search of the literature yielded 26 studies that investigated vertical ground reaction force, axial tibial acceleration, loading rate and local plantar pressures. Meta-analyses of the effect of shoes on each variable during walking and running were performed using the inverse variance technique. Variables were collected at their peak or at the impact transient, but when grouped together as previous comparisons have done, shoes reduced local plantar pressure and tibial acceleration, but did not affect vertical force or loading rate for walking. During running, shoes reduced tibial acceleration but did not affect loading rate or vertical force. Further meta-analyses were performed, isolating shoe type and when the measurements were collected. Athletic shoes reduced peak vertical force during walking, but increased vertical force at the impact transient and no change occurred for the other variables. During running, athletic shoes reduced loading rate but did not affect vertical force. The range of variables examined and variety of measurements used appears to be a reason for the discrepancies across the literature. The impact attenuating effect of shoes has potentially both adverse and beneficial effects depending on the variable and activity under investigation.

Mechanics of jazz shoes and their effect on pointing in child dancers.

There has been little scientific investigation of the impact of dance shoes on foot motion or dance injuries. The pointed (plantar-flexed) foot is a fundamental component of both the technical requirements and the traditional aesthetic of ballet and jazz dancing. The aims of this study were to quantify the externally observed angle of plantar flexion in various jazz shoes compared with barefoot and to compare the sagittal plane bending stiffness of the various jazz shoes. Sixteen female recreational child dancers were recruited for 3D motion analysis of active plantar flexion. The jazz shoes tested were a split-sole jazz shoe, full-sole jazz shoe, and jazz sneaker. A shoe dynamometer measured the stiffness of the jazz shoes. The shoes had a significant effect on ankle plantar flexion. All jazz shoes significantly restricted the midfoot plantar flexion angle compared with the barefoot condition. The split-sole jazz shoe demonstrated the least restriction, whereas the full-sole jazz shoe the most midfoot restriction. A small restriction in metartarsophalangeal plantar flexion and a greater restriction at the midfoot joint were demonstrated when wearing stiff jazz shoes. These restrictions will decrease the aesthetic of the pointed foot, may encourage incorrect muscle activation, and have an impact on dance performance.

Effect of footwear on dancers: a systematic review.

Dancers need their feet to be healthy and pain-free; therefore, the footwear they use is of great importance. Footwear has the potential to enhance or restrict movement and impact the dancer's body in various ways. To evaluate the effects of footwear on dancers, in particular the effects on foot motion and injury during dance movements, we undertook a systematic review of the literature. The major databases were searched for articles on theatrical dance styles and dance footwear. Sixteen articles were selected for inclusion in this study, ten on ballet and the remainder covering a variety of other genres. The contribution of dance shoes to the quality of dance movement is a relatively unexplored subject; little experimental research has been done. Prospective scientific evidence is needed to support or disprove traditional beliefs regarding the effects of footwear on dance performance and dancers' health.