The usefulness of performance matrix tests in locomotor system evaluation of girls attending a ballet school - preliminary observation.
[Purpose] Learning ballet is connected with continuous use of the locomotor system while subjecting it to high loads. Therefore, we conducted some research defining the appearance of weak links in the motor system, in order to eliminate the risk of injury. [Methods] Fifty-two female students of a ballet school were examined. To identify weak links, low-threshold Performance Matrix tests were performed. An analysis of weak link occurrence in the locomotor system was carried out, using two way analysis of variance ANOVA Tukey's HSD test, clustering methods and Principal Component Analysis (PCA). [Results] The average age of the subjects was 11.64±0.53 years (mean ± standard deviation), their average body height was 151.1±7.5 cm, their average body weight was 35.92±5.41 kg, and their average time of learning at ballet school was 2.17±0.65 years. We found that there were significant differences in weak links occurrence in the motor system of every girl examined. [Conclusions] Weak links were found in every location of the motor system. Our results show that the influence of weak link location is essentially different from their occurrence, and that learning ballet has a significantly different impact on the number of weak links in different locations.