Classical ballet dancing is a good model for studying the long-term activity-dependent plasticity of the central nervous system in humans, as it requires unique ankle movements to maintain ballet postures. The purpose of this study was to investigate whether postactivation depression is changed through long-term specific motor training. Eight ballet dancers and eight sedentary subjects participated in this study. The soleus Hoffmann reflexes were elicited at after the completion of a slow, passive dorsiflexion of the ankle. The results demonstrated that the depression of the soleus Hoffmann reflex (i.e., postactivation depression) was larger in classical ballet dancers than in sedentary subjects at two poststretch intervals. This suggests that the plastic change through long-term specific motor training is also expressed in postactivation depression of the soleus Hoffmann reflex. Increased postactivation depression would strengthen the supraspinal control of the plantarflexors and may contribute to fine ankle movements in classical ballet dancers.
Keywords: activity-dependent plasticity; classical ballet dancer; spinal reflex.