Gorwa Joanna, Michnik Robert A, Nowakowska-Lipiec Katarzyna, Jurkojć Jacek, Jochymczyk-Woźniak Katarzyna
Department of Biomechanics, Chair of Theory and Methodology of Sport, Faculty of Sport Sciences, Poznań University of Physical Education, Poznań, Poland.
Department of Biomechatronics, Faculty of Biomedical Engineering, Silesian University of Technology, Zabrze, Poland.
Acta Bioeng Biomech. 2019;21(4):111-121.
The objective of the work was to determine biomechanical parameters influencing loads affecting the musculoskeletal system and shock absorption during the landing phase in Grand Jeté, Entrelacé and Ballonné.
Motion kinematics measurements of the landing phase in GrandJeté, Entrelacé and Ballonné were carried out using the optical APAS system, and measurements of the GRF components - using Kistler platform. The research was carried out for three professional dancers. Kinematic and kinetic parameters of the landing were analysed.
The mean maximum GRF value in relation to the classical dancer amounted to 8.16 ± 1.37 N/BW. During landing, the joints of the lower limb are affected by external force moments of high values (ankle - 3.04 ± 0.54 [Nm/BW], knee - 7.56 ± 5.53 [Nm/BW], hip - 10.97 ± 6.80 [Nm/BW]). The maximum value of the external force moments in the joint were strongly negatively correlated with the value of the angle in the hip joint at the moment of the first contact with the ground. It was noticed that the obtainment of maxGRF was preceded by a decrease in kinetic energy of approximately 50%.
Factors affecting loads present in the musculoskeletal system during the shock absorption of a leap are: GRF values, the values of external force generated inside the joints and a change in the value of kinetic energy. The safe shock absorption after landing is influenced by properly positioned limb at the moment of the first contact, a greater range of movements in the joints and longer time from the moment of the first contact to the obtainment of maxGRF.
本研究的目的是确定影响大跳、交织步和抛跳落地阶段肌肉骨骼系统负荷及减震效果的生物力学参数。
使用光学APAS系统对大跳、交织步和抛跳的落地阶段进行运动学测量,并使用奇石乐平台测量地面反作用力(GRF)分量。研究针对三名专业舞者进行。分析了落地的运动学和动力学参数。
与古典舞者相比,平均最大GRF值为8.16±1.37N/体重。落地过程中,下肢关节受到高值外力矩的影响(踝关节-3.04±0.54[Nm/体重],膝关节-7.56±5.53[Nm/体重],髋关节-10.97±6.80[Nm/体重])。关节处外力矩的最大值与首次接触地面瞬间髋关节角度值呈强负相关。研究发现,最大GRF的出现之前动能大约下降了50%。
跳跃减震过程中影响肌肉骨骼系统负荷的因素包括:GRF值、关节内部产生的外力值以及动能值的变化。落地后安全减震受首次接触瞬间肢体的正确摆放、关节更大的活动范围以及从首次接触到获得最大GRF的更长时间影响。