Static balance and dynamic balance related to rotational movement in ballet dance students
The aim of this study was to assess static and dynamic balance related to rotational movements en pointe and en demi pointe in ballet dance students. The study group consisted of 13 people – students of one of the ballet schools in Poland: 9 dancers from the junior class (14 years old) and 4 dancers form the senior class (18 years old). For the purpose of statistical analysis, the group was divided into 4 subgroups. Each person took part in a static balance test which included a 30s trial with eyes opened and 30s trial with eyes closed. The examination of dynamic balance related to rotational movements was also performed to compare movements en pointe vs. movements en demi pointe. Analyses were performed using the Kistler 9286BA platforms, which are the module of BTS Smart DX 7000. Data processing was performed with the use of BTS Sway and Statistica 10. Accepted level of significance was α = 0.05. Increase in the following center of pressure parameters was observed in the examination with eyes closed: maximal radius, longitudinal range, equivalent area and velocity. Participants from the senior class did not show these differences. There were no differences found between movements en demi pointe in comparison with movements en pointe. Static balance deteriorated with eyes closed in the entire examined group. Participants from the senior class showed more stable parameters of static balance. There were no differences in dynamic balance when the base of support was decreased.