On the track of the ideal turnout: Electromyographic and kinematic analysis of the five classical ballet positions

Abstract

The turnout of the lower extremities is the major component of the classical ballet positions (CPs) and correctly is initiated in the hips. The aim of this research was to determine the differences in the electromyographic and kinematic variables in the five CPs in ballet students with greater and lesser amount of passive hip external rotation (HER). A group of 14 female pre-professional ballet dancers 11-16 years of age participated in the study. Based on the amount of passive HER, participants with higher values made up greater rotation group (n = 7) whereas those with lesser values formed lesser rotation group (n = 7). Electromyographic activity of 14 muscles from right side of the trunk and right lower extremity was recorded with the surface electrodes while subjects were standing in all five CPs (CP1-CP5). The external rotation of the hips, knees and feet were recorded with the motion capture system. The kinematic differences between the groups were revealed in asymmetric positions CP4 and CP5 where foot progression angle was significantly lesser in forward than backward setting only in lesser rotation group. In lesser rotation group the ankle and back muscles were more engaged in CPs while abdominal and hip muscles less when compared with greater rotation group. This finding suggests that in the group with lesser passive HER the mechanism of forced turnout was employed. The most remarkable finding in our work was that various electromyographic patterns can be observed between groups in all CPs, while kinematic differences may be marked only in asymmetric positions.

Biomechanical Description of Zapateado Technique in Flamenco

“…Positions and movements involving end-range extension are an integral part of the dance aesthetic. The biomechanical analysis of the human locomotor system revealed that unfavorable situations are those when muscles are subjected to long isometric tension and when muscles stabilize the multisegment biomechanism bases [ 14 ]. It seems that the flamenco falls well within the scheme of the aforementioned static loads.…”

“…This causes a stiffness that could cause overloads in the back muscles. The use of the abdominal muscles and hip extensors (buttocks) is of great importance in the correct pelvis stabilizing process [ 14 ].…”

“…Abdominal muscles stabilize the trunk and limit the anterior pelvic tilt which, if exaggerated, is adverse. The results of the Gorwa et al (2020) study indicate that at least the effectiveness of exercises aimed at the engagement of the abdominal muscles in keeping the pelvis stable in the sagittal plane should be evaluated and monitored in young dancers [ 14 ]. These muscles will have the same importance in flamenco, where the main movement task is played by the lower limbs with a stabilized pelvis.…”

In Pursuit of the Perfect Dancer’s Ballet Foot. The Footprint, Stabilometric, Pedobarographic Parameters of Professional Ballet Dancers

“…The height of the longitudinal arch of the foot seems to be an inborn feature [ 22 ]. Ballet exercises may slightly increase the aforementioned feature, yet they primarily affect foot muscles [ 23 ].…”

“…The vertical components of ground reaction forces act locally on the ballet dancer’s skeletal system making femoral necks highly mineralised and radial bones (not loaded) osteopenic [ 29 ]. The adoption of ballet positions is responsible for the unnaturally high involvement of lower limb muscles and pathological pelvis positions [ 23 ]. At the same time, feet exercises lead to specific geometric changes in the aforesaid structures, such as hallux valgus [ 27 ].…”