In order to determine the correlation between the H- reflex modulation and limits of stability in ballet dancers, we measured the amplitude of H-reflex and performed four-way-leaning test of limits of stability. H-reflex was measured to eight professional ballet dancers, active members of Slovenian national ballet in Ljubljana and Maribor (1 male and 7 female, mean age: 25±4,2 years, mean height: 169,25±5,4 cm and an average weight: 56,45±10,1 kg). All participants completed at least 10 years of dance education. Reflex H was measured in 3 conditions: prone, bipedal stance and unipedal stance. The results showed that the ratio of the largest wave H/wave M in bipedal and unipedal stance was lower than in prone. The ratio of the maximum wave H/wave M decreased by 53.3±22.6 % (P <0.001) from prone to the bipedal stance, compared with prone, while in the unipedal stance ratio was 45.2±26.1 % (P <0.001) lower than in prone. The decrease in modulation of reflex H was due to pre-synaptic inhibition. Among the measured variables of the four-way leaning test of limits of stability, the negative connection was determined only with the variable maximal body lean in all four directions. It seems that the modulation of the reflex H in the bipedal and unipedal stance is not a suitable test for assessing the active weight transfer within the support surface.
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