1Neuromusculoskeletal Mechanics Research Program, Faculty of Physical Education and Recreation; and 2Department of Mechanical Engineering, University of Alberta, Edmonton, Alberta, Canada.
J Strength Cond Res. 2013 Dec;27(12):3225-32. doi: 10.1519/JSC.0b013e31828ddf19.
Jumping and weightlifting tasks involve impact phases, where work is performed by the lower extremity to absorb energies present at contact. This study compared the lower extremity kinematic and kinetic strategies to absorb energy during the impact phase of jumping and weightlifting activities. Ten women experienced in jumping and weightlifting performed 4 tasks (landing from a jump, drop landing, clean, and power clean) in a motion analysis laboratory. Work performed at the hip, knee, and ankle were calculated during the landing and receiving phases of jumping and weightlifting tasks, respectively. Additionally, segment and joint kinematics and net joint moments were determined. The most lower extremity work was performed in the clean and drop landing, followed by landing from a jump, and the least work was performed in the power clean (p < 0.05). For all tasks, work performed by the knee extensors was the greatest contributor to lower extremity work. Knee extensor net joint moment was greater in the power clean than jump and drop landings, and greater in the clean than all other tasks (p < 0.05). Knee flexion angle was not different between the power clean and jump landing (p > 0.05) but greater in the drop landing and clean (p < 0.05). A common characteristic of the impact phase of jumping and weightlifting tasks is a large contribution of knee extensor work. Further, the correspondence in kinematics between impact phases of jumping and weightlifting tasks suggests that similar muscular strategies are used to perform both types of activities. Weightlifting tasks, particularly the clean, may be important exercises to develop the muscular strength required for impact actions due to their large knee extensor net joint moments.
跳跃和举重任务涉及冲击阶段，在此阶段，下肢通过吸收接触时的能量来完成工作。本研究比较了跳跃和举重活动冲击阶段吸收能量时下肢运动学和动力学策略。10 名有跳跃和举重经验的女性在运动分析实验室中完成了 4 项任务（从跳跃中着陆、跳下着陆、清洁和力量清洁）。在跳跃和举重任务的着陆和接收阶段分别计算了髋关节、膝关节和踝关节的功。此外，还确定了节段和关节运动学以及净关节力矩。在清洁和跳下着陆时下肢做功最大，其次是从跳跃中着陆，而在力量清洁时做功最小（p < 0.05）。对于所有任务，膝关节伸肌完成的功最大。与跳跃和跳下着陆相比，力量清洁时的膝关节伸肌净关节力矩更大，而与所有其他任务相比，清洁时的膝关节伸肌净关节力矩更大（p < 0.05）。力量清洁时的膝关节屈曲角度与跳跃着陆时无差异（p > 0.05），但在跳下着陆和清洁时更大（p < 0.05）。跳跃和举重任务冲击阶段的一个共同特征是膝关节伸肌做功很大。此外，跳跃和举重任务冲击阶段的运动学相似表明，这两种类型的活动使用相似的肌肉策略来完成。举重任务，特别是清洁，由于其较大的膝关节伸肌净关节力矩，可能是发展冲击动作所需肌肉力量的重要练习。
