Lin Chia-Wei, Su Fong-Chin, Lin Cheng-Feng
Institute of Biomedical Engineering, College of Engineering, National Cheng Kung University, Tainan City, Taiwan.
J Appl Biomech. 2014 Feb;30(1):37-49. doi: 10.1123/jab.2012-0068. Epub 2013 May 13.
Ballet deep squat with legs rotated externally (grand plié) is a fundamental movement for dancers. However, performing this task is a challenge to ankle control, particularly for those with ankle injury. Thus, the purpose of this study was to investigate how ankle sprains affect the ability of postural and muscular control during grand plié in ballet dancers. Thirteen injured dancers and 20 uninjured dancers performed a 15 second grand plié consisting of lowering, squatting, and rising phases. The lower extremity motion patterns and muscle activities, pelvic orientation, and center of pressure (COP) excursion were measured. In addition, a principal component analysis was applied to analyze waveforms of muscle activity in bilateral medial gastrocnemius, peroneus longus, and tibialis anterior. Our findings showed that the injured dancers had smaller pelvic motions and COP excursions, greater maximum angles of knee flexion and ankle dorsiflexion as well as different temporal activation patterns of the medial gastrocnemius and tibialis anterior. These findings suggested that the injured dancers coped with postural challenges by changing lower extremity motions and temporal muscle activation patterns.
双腿外旋的芭蕾舞深蹲（大踢腿蹲）是舞者的一项基本动作。然而，完成这项任务对踝关节控制是一项挑战，尤其是对于那些有踝关节损伤的人。因此，本研究的目的是调查踝关节扭伤如何影响芭蕾舞舞者在大踢腿蹲时的姿势和肌肉控制能力。13名受伤舞者和20名未受伤舞者进行了一个15秒的大踢腿蹲，包括下降、下蹲和上升阶段。测量了下肢运动模式和肌肉活动、骨盆方向以及压力中心（COP）偏移。此外，应用主成分分析来分析双侧腓肠肌内侧头、腓骨长肌和胫骨前肌的肌肉活动波形。我们的研究结果表明，受伤舞者的骨盆运动和COP偏移较小，膝关节最大屈曲角度和踝关节背屈角度更大，以及腓肠肌内侧头和胫骨前肌的时间激活模式不同。这些结果表明，受伤舞者通过改变下肢运动和时间肌肉激活模式来应对姿势挑战。
