McDonnell Jessica, Willson John D, Zwetsloot Kevin A, Houmard Joseph, DeVita Paul
Department of Kinesiology, East Carolina University, Greenville, NC 27858, United States.
Department of Physical Therapy, East Carolina University, Greenville, NC 27858, United States.
J Biomech. 2017 Nov 7;64:180-185. doi: 10.1016/j.jbiomech.2017.09.039. Epub 2017 Oct 7.
The inherit injury risk associated with high-impact exercises calls for alternative ways to achieve the benefits of aerobic exercise while minimizing excessive stresses to body tissues. Skipping presents such an alternative, incorporating double support, flight, and single support phases. We used ground reaction forces (GRFs), lower extremity joint torques and powers to compare skipping and running in 20 healthy adults. The two consecutive skipping steps on each limb differed significantly from each other, and from running. Running had the longest step length, the highest peak vertical GRF, peak knee extensor torque, and peak knee negative and positive power and negative and positive work. Skipping had the greater cadence, peak horizontal GRF, peak hip and ankle extensor torques, peak ankle negative power and work, and peak ankle positive power. The second vs first skipping step had the shorter step length, higher cadence, peak horizontal GRF, peak ankle extensor torque, and peak ankle negative power, negative work, and positive power and positive work. The first skipping step utilized predominately net negative joint work (eccentric muscle action) while the second utilized predominately net positive joint work (concentric muscle action). The skipping data further highlight the persistence of net negative work performed at the knee and net positive work performed at the ankle across locomotion gaits. Evidence of step segregation was seen in distribution of the braking and propelling impulses and net work produced across the hip, knee, and ankle joints.
Skipping was substantially different than running and was temporally and spatially asymmetrical with successive foot falls partitioned into a dominant function, either braking or propelling whereas running had a single, repeated step in which both braking and propelling actions were performed equally.
与高强度运动相关的固有受伤风险促使人们寻找替代方法，以在将对身体组织的过度压力降至最低的同时，实现有氧运动的益处。跳绳就是这样一种替代方式，它包含双支撑、腾空和单支撑阶段。我们使用地面反作用力（GRF）、下肢关节扭矩和功率，对20名健康成年人的跳绳和跑步进行了比较。每条腿上连续的两个跳绳步骤彼此之间以及与跑步都有显著差异。跑步的步长最长，垂直GRF峰值、膝关节伸肌扭矩峰值、膝关节负向和正向功率以及负向和正向功最高。跳绳的节奏更快，水平GRF峰值、髋关节和踝关节伸肌扭矩峰值、踝关节负向功率和功峰值以及踝关节正向功率峰值更高。第二个跳绳步骤与第一个相比，步长更短，节奏更快，水平GRF峰值、踝关节伸肌扭矩峰值、踝关节负向功率、负向功、正向功率和正向功更高。第一个跳绳步骤主要利用净负向关节功（离心肌肉动作），而第二个主要利用净正向关节功（向心肌肉动作）。跳绳数据进一步突出了在不同运动步态中，膝关节处净负向功和踝关节处净正向功的持续性。在髋、膝和踝关节产生的制动和推进冲量以及净功的分布中，可以看到步间差异的证据。
跳绳与跑步有很大不同，在时间和空间上不对称，连续的脚步落地被划分为主要功能，即制动或推进，而跑步有一个单一的、重复的步骤，其中制动和推进动作同等执行。
