Faculty of Human Kinetics, University of Lisbon, Lisbon, PORTUGAL.
Sports Medicine Assessment, Research & Testing (SMART) Laboratory, George Mason University, Manassas, VA.
Med Sci Sports Exerc. 2019 Mar;51(3):539-547. doi: 10.1249/MSS.0000000000001817.
This study aimed to compare lower extremity (LE) biomechanics between professional dancers (PD) and nondancers (ND) during multidirectional single-leg landings.
Fifteen PD (27 ± 7 yr, 1.69 ± 0.1 m, 57.8 ± 9.3 kg) and 15 ND (25 ± 5 yr, 1.69 ± 0.1 m, 66 ± 10.2 kg) performed single-leg jumps in three directions: 1) lateral, 2) diagonal, and 3) forward. Dominant LE biomechanical data were collected using a motion capture system. Data were processed in Visual3D. LE kinematic (hip, knee, and ankle joint angles in sagittal and frontal planes, and range of motion [ROM]) and kinetics (hip and knee internal joint moments and vertical ground reaction force) variables were analyzed at initial contact (IC), peak vertical ground reaction force (PvGRF), and peak knee flexion (PKF). Repeated-measures ANOVA was conducted (P < 0.05).
At IC, statistically significant interactions were found for ankle frontal and hip sagittal angles (P < 0.05). The main effects for groups and jump directions were attained (P < 0.05). PD at IC had lower hip and knee flexion and higher ankle plantarflexion than ND. PD had significantly higher knee (PD, 41 ± 6.1; ND, 33.8 ± 8.4) and ankle (PD, 53.7 ± 3.4; ND, 38.9 ± 8.9) ROM than ND. At IC, the lateral jump had higher hip abduction moment, hip abduction, and ankle inversion and lower hip flexion and ankle plantarflexion than the forward and diagonal jumps. The lateral jump (15.5 ± 7.7) had higher hip excursion than the forward jump (12.7 ± 5.4).
The higher extended posture of PD at IC promoted an efficient use of the knee and ankle ROM to dissipate the landing forces. Regardless of the group, jump directions also solicited different biomechanical responses, particularly between lateral and forward directions. These strategies should be considered for implementation in prevention programs, as it can foster adequate LE neuromuscular control.
本研究旨在比较专业舞者(PD)和非舞者(ND)在多方向单腿着陆时下肢(LE)的生物力学差异。
15 名 PD(27±7 岁,1.69±0.1 m,57.8±9.3 kg)和 15 名 ND(25±5 岁,1.69±0.1 m,66±10.2 kg)分别进行了三个方向的单腿跳跃:1)横向,2)对角,3)向前。使用运动捕捉系统采集优势侧下肢运动学(矢状面和额状面的髋关节、膝关节和踝关节角度,以及运动范围 [ROM])和动力学(髋关节和膝关节的关节内力矩和垂直地面反作用力)数据。在初始接触(IC)、最大垂直地面反作用力(PvGRF)和最大膝关节屈曲(PKF)时对数据进行分析。采用重复测量方差分析(P<0.05)。
在 IC 时,踝关节额状面和髋关节矢状面角度存在显著的交互作用(P<0.05)。组间和跳跃方向的主要效应均达到统计学意义(P<0.05)。PD 在 IC 时的髋关节和膝关节屈曲度较低,踝关节背屈度较高,与 ND 相比。PD 的膝关节(PD,41±6.1;ND,33.8±8.4)和踝关节(PD,53.7±3.4;ND,38.9±8.9)ROM 明显更高。在 IC 时,横向跳跃的髋关节外展力矩、髋关节外展和踝关节内翻较大,髋关节屈曲和踝关节跖屈较小,与向前和对角跳跃相比。与向前跳跃(12.7±5.4)相比,横向跳跃(15.5±7.7)的髋关节活动度更高。
PD 在 IC 时保持的较高伸展姿势促进了膝关节和踝关节 ROM 的有效利用,以消耗着陆力。无论组别如何,跳跃方向也会引起不同的生物力学反应,尤其是横向和向前方向之间。这些策略应考虑纳入预防计划中,以促进下肢适当的神经肌肉控制。