Rotation is Your Motivation: Phase 1

The Rotation is Your Motivation research project attempts to collect all myths, knowledge, and movement material used to work on the hip rotation. 

Researchers agree that available external hip rotation coupled with the tibia and foot's various contributions rarely add up to the magical 90 degrees turn-out. There is a vast array of individual differences in human bodies. There are many considerations in optimizing turn-out safely. As dance teachers and dancers learn anatomy and the biomechanics of turn-out, both general and individual, they will understand, evaluate and apply sound methods to improve turn-out and optimize dynamic function. The hip joint rotation is one of the most discussed issues in dance. Many myths and traditional practices try to help students reach extreme external rotation, but many studies show that the hips will lose external rotation after 12-13 years. Less external rotation helps them with stability but might give them a more challenging time with mobility. The emphasis should be on maintaining flexibility without losing the positive effect of stability.  

Introduction: 

In classical ballet dance, the basic requirement and the most important anatomical feature to perform the movements is the extreme passive rotation of the hip joint. In contemporary dance, this ability is not necessary. Therefore, the two dance styles require different training methods. We aim to show the differences in bone structure and hip joint geometry parameters by dance style and gender and the correlations with bone fractures.

Material and method: 

A total of 49 dancers, 25 women and 24 men (age 19-36 years) participated in the densitometry. The subjects graduated from various Hungarian ballet and contemporary dance academies. Bone structure parameters were measured by the DEXA method. Using special software, we also performed complete hip analysis (AHA), hip bone geometry (ROI), and accurate determination of hip neck-axis angle (θ) and axis length (HAL), respectively. Statistical analysis was performed in software environment R. Binomial regression models were fitted separately to analyze the results, and correlations were examined using correlation. The significance level was 5% in all cases, and trends were interpreted at the 10% level.

Conclusion:  

We have shown a difference in bone structure parameters as a body region as a dance style since ballet dancers receive less strain on their upper bodies. In contrast, the daily routine of contemporary dancers includes weighting on the arms.

The measurements of external and internal hip rotations showed no significant correlation between the length of the neck of the femur and the angle of the neck of the femur. We can conclude, that there is no relation between the geometry of the femur and the ability to rotate the hip joint. This is in a way it is good news for dance teachers because the shape of the bone does not affect the movement. But our data shows a correlation between starting ballet training early, before puberty, and external rotation. This might be because the ligaments are more supple and adaptable during childhood.

Dance is undergoing constant change and development. We can create new styles, new qualities, and new challenges. These new motion patterns aim to push our creative and physical boundaries, providing a continuous research platform for a more accurate understanding of our anatomical features.

Dance can be art and science practice at the same time. Training the body to become a skilled professional dancer is a highly scientific practice: it involves anatomy and sports science. However, the outcome of all the training is performance art, not competition. That is why artistic creation is considered more important than the scientific reality of the body. In the name of Art, many dancers suffer physically and psychologically. In the wake of cultural and social changes, the dance world must also wake up. We need new ethical guidelines, implement structural and institutional change, and conduct scientific research on artistic methods to generate the changes. Furthermore, we need to educate dancers on evidence-based lifestyle choices to avoid serious health consequences. In this thesis, we use a scientific research method to point out harmful artistic practices to draw attention to misconduct in the dance field.

The project deals with the relationship between anatomical structure and aesthetic values in dance. The project's title refers to the work of William Forsythe, using the rotation of the hip as motivation for improvised movement material. The extreme external rotation of the hip joint is an essential movement in ballet technique. But is this tradition relevant to contemporary dance techniques? 

Dr. Irina Kalabiska, sports physiology researcher, and Zsuzsa Rózsavölgyi choreographer, a movement researcher, conducted a scientific inquiry on the anatomy of the hip joint. Zsuzsa Rózsavölgyi further explored the functionality of hip rotation in movement and how it affects artistic expression. Laura Tóth, choreographer and dancer, participated in creating the movement material, and Bolgárka Simon-Hatala helped us with her physiotherapist knowledge.

The project's research area is the relationship between anatomical structure and aesthetic values in dance and movement research. We want to determine if function and aesthetics are the same in contemporary dance techniques by evaluating the dancer's hip joint structure and movement possibilities.

Questions:

What are the advantages and disadvantages of having extreme external rotation or excessive internal rotation? 

Is there a difference between aesthetic values and functional values of hip rotation?

What advantages do we gain from old traditions and myths about rotation?

Are there any disadvantages of newly acquired knowledge from anatomical research within the art of dance?

The project had two phases: 

– The scientific phase: We measured the hip joint's external and internal rotation on volunteering dancers, and we will take pictures of their hips with a machine called: DEXA (Dual Energy X-ray Absorptiometry). We evaluated a correlation between the angle of the femur's head and its external and internal hip rotation.

Short movie about the scientific phase: https://vimeo.com/679794121

– The artistic phase: We created improvised and fixed movement material for two dancers, one with more external hip rotation and one with more internal hip rotation. Then we saw any significant differences in how the movements look on different bodies. After the movement research phase, we created a lecture-performance about the traditional point of view and the contemporary point of view on the hip joint's ability in artistic expression. 

Video link for the artistic phase: https://vimeo.com/832376389

Methods

Place and the supervisor of the project:

The research took place at the University of Physical Education in Budapest. The research supervisor was Dr. Irina Kalabiska, who researches Medical Anthropology, Radiology, and Sports Medicine. We applied to the Research Ethics Committee of the University of Physical Education in Budapest for the Research Ethics Approval. We received the approval on February 24, 2021. We took the measurements from 22-26. February 2021.

Research subjects:

The study involved 49 dancers: 24 male and 25 female, 24 ballet and 25 contemporary dancers. We divided the participants into four groups:

- 11 male ballet dancers,

- 13 female ballet dancers,

- 13 male contemporary dancers,

- 12 female contemporary dancers.

The ballet dancers participating in the study graduated from the Hungarian Dance University, the contemporary dancers studied in the Budapest Contemporary Dance Academy.

Participants in the research had to meet the following criteria:

- professional dance studies,

- for ballet dancers: a minimum of four years of daily ballet training six

times a week,

- for contemporary dancers: a minimum of four years of daily contemporary

dance training five times a week,

- After their studies, they are still active dancers.

Exclusion criteria from the research were:

- Of a bodyweight exceeding 136 kg,

- test person with orthopedic metallic devices,

- the presence of X-ray contrast in the body,

- the presence of a radiating isotope in the body,

- pregnancy.

Methods for examining anthropometric factors:

We analyzed the anthropometric characteristics of the dancers by descriptive statistical method. We calculated the mean, standard deviation of age, height, body weight, and body mass index. The examined indicators were by four different comparisons:

- Gender: averages of male and female dancers.

- Divided into dance styles: averages of ballet and contemporary dancers.

- Divided by dance styles and gender: averages of male ballet and male

contemporary dancers.

- Divided by dance styles and gender: averages of female ballet and female

contemporary dancers.

Measuring external hip rotation:

We measured the active hip rotation by drawing a first position on a paper and measure the angle between the feet. 

We measured the passive hip rotation with a goniometer.

During the artistic research phase, we used the results of the scientific research phase to ensure that the rotation capacity of the hip joint between two dancers can be significant. We choose two dancers with opposite capabilities. Then, we went through many hip joint movements to see where the different capabilities were the most impressive. We created improvised and fixed movement material, one with more external hip rotation and one with more internal hip rotation. We saw significant differences in how the movements looked on different bodies. Then, we created a movement material that tried to dance the material in unison, but we failed because of the anatomical advantages and disadvantages. After the movement research phase, we created a lecture performance about the traditional and contemporary points of view on the hip joint's ability for artistic expression. 

 

Body composition analysis:

DEXA (Dual-Energy X-ray Absorptiometry) is a scanning device using x-ray technology to measure body composition. The machine determines the distribution of bone, muscle, fat, and water content of the body. DEXA is the gold standard in tissue determination because it gives accurate results. DEXA measures:

- bone mass,

- muscle mass,

- fat mass,

- fat percentage,

- bone mineral density,

- bone mineral content

- visceral fat tissue (central abdominal fat).

It can measure the tissue content of the total body and body parts: left and right side of the trunk, left and right side of the legs, and the arms.

DEXA most often is used for Bone Densitometry measurements, identifying osteoporosis. T score is the Bone Mineral Density compared to young adults of the same gender in peak health:

- normal score: -1 and above,

- osteopenia: -1 to -2.5,

- osteoporosis: below -2.5.

For this research, we used the DEXA data of BMI (Body Mass Index) and BMD data (Bone Mineral Density) in four body regions: Legs, arms, trunk, and hips.