Investigation of classical ballet rotational movement skills with pointe shoes ― Quantitative and qualitative analysis ―

To investigate the elements of the aesthetic rotational movement with pointe shoes considering both quantitative and qualitative factors.

A questionnaire survey, motion analysis, and evaluation from the viewers were conducted. Word lists were created based on the questionnaire survey regarding the beautiful turning from 108 ballet dancers. We conducted qualitative analysis (frequent word analysis and co-occurrence networks) to confirm and extract the viewpoints. Ten dancers (age: 24.7±3.5 y.o.，height：157.7±6.5 cm, body weight：48.3±5.0 kg, ballet experience：19.5±4.8 years) joined the motion analysis and they conducted ballet turns. Retroreflective markers were applied to 35 body sites based on the Plug-In Gait full-body model. An 8-camera motion-capture system (Vicon MX, 250 Hz) and two force plates (Kistler, 1,000 Hz) were used for data collection while the motion was recorded with the video. The videos were shown to the ten evaluators (age: 34.9±16.1 y.o., ballet experience：21.5±15.5 years) and they judged ten dancers’ performance depending on the extracted viewpoints list from the qualitative analysis. Spearman's rank correlation coefficient was calculated with the parameters obtained by the movement analysis, which were considered related to the evaluation items.

The results of correlation analysis between the biomechanics variables and evaluation scales suggest that the vertical position of the second metatarsal of the gesture leg (r=0.87, p0.01), the change in inclination of the line from the left to right shoulders (r= -0.80, p0.01), and the change in inclination of the line from the lateral malleolus to the head center (r= -0.69, p0.01) were associated with total score.

This study concludes that the elements of aesthetic rotation wearing pointe shoes is influenced by the movements of the feet, shoulders, and other body parts, which can be visually perceived by the viewer.

In the exploration of movement skills, incorporating a qualitative assessment that considers the practitioner’s body awareness and examining the relationship between qualitative and quantitative variables suggests the possibility of articulating the necessary elements of movement. This indicates the need for interpretation in terms of the quality of the movement performed when teaching in rehabilitation and sports settings.