To test Bernstein’s degrees of freedom (DF) hypothesis, the authors analyzed the effect of practice on the DF control and interjoint coordination of a Taekwondo kick. Thirteen inexperienced and 11 expert Taekwondo practitioners were evaluated. Contrary to Bernstein’s hypothesis, the inexperienced group froze the DF at the end of learning, reducing the joint range of motion of the knee. Moderate and strong cross-correlations between joints did not change, demonstrating that the interjoint coordination was maintained. The inexperienced group’s movement pattern was similar to that of the group of experts, from the beginning of the learning process. Thus, even after years of practice, experts continue to explore the strategy of freezing DF. The DF freeing/freezing sequence strategy was explored during the learning process, suggesting that DF-freezing/freeing strategies are task dependent.

为了检验伯恩斯坦的自由度（DF）假设，作者分析了练习对跆拳道踢的DF控制和关节间协调的影响。对13名缺乏经验的跆拳道从业人员和11名跆拳道从业人员进行了评估。与伯恩斯坦的假设相反，经验不足的小组在学习结束时冻结了DF，从而减小了膝盖的关节活动范围。关节之间的中度和强互相关性没有改变，表明关节间的协调得以维持。从学习过程开始，经验不足的小组的行动模式与专家小组的类似。因此，即使经过多年的实践，专家们仍在继续探索冻结DF的策略。在学习过程中探索了DF释放/冻结序列策略，