Currently, there are several computational methods for stiffness during a hopping task, but they do not necessarily yield the same values. Therefore, it is essential that the simplicity of the equipment used does not affect the measurement validity. The aim of this study is to compare the stiffness values during a hopping task recorded in a laboratory environment and those acquired using the Myotest accelerometer. The measurements were performed on a group of 30 untrained female students (age: years, body height: , and body mass: ). According to the manual for the Myotest accelerometric system, each study participant performed three sets of 5 hops. Vertical stiffness was determined based on two measurement methods, one using the Myotest accelerometer and the other using Kistler force plates. The mean value (±SD) of vertical stiffness was in the countermovement phase and in the take-off phase. Furthermore, the stiffness determined using the Myotest was . However, significant relationships between the vertical stiffness in the countermovement phase and the Myotest stiffness () and between the vertical stiffness in the take-off phase and the Myotest stiffness () were found. The relationships between the vertical stiffness (in the countermovement and take-off phases) and the stiffness estimated using the Myotest allow us to conclude that despite the significantly overestimated stiffness value, the Myotest accelerometer can still be used for determination of the stiffness trends, e.g., following training. The overestimated stiffness values can result both from inaccuracy in the determination of ground contact time and flight time by the Myotest accelerometer and from the use of an equation that assumes that the movement of the center of mass has a harmonic profile.

中文翻译：

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加速度计系统在确定跳跃任务期间的刚度方面的应用。

当前，在跳跃任务期间，存在几种用于刚度的计算方法，但是它们不一定会产生相同的值。因此，至关重要的是所用设备的简单性不会影响测量的有效性。这项研究的目的是比较在实验室环境中记录的跳动任务期间的刚度值和使用Myotest加速度计获得的刚度值。测量是对30名未经训练的女学生进行的（年龄： 年，身高： ，和体重：）。根据Myotest加速度计系统手册，每个研究参与者进行了3组5跳。垂直刚度是根据两种测量方法确定的，一种使用Myotest加速度计，另一种使用奇石乐测力板。垂直刚度的平均值（±SD）为 在反向运动阶段 在起飞阶段。此外，使用Myotest测定的刚度为。但是，反向运动阶段的垂直刚度与Myotest刚度之间存在显着的关系（）以及起飞阶段的垂直刚度和Myotest刚度（）被发现。垂直刚度（在反向运动和起飞阶段）与使用Myotest估算的刚度之间的关系可以使我们得出结论：尽管明显高估了刚度，但Myotest加速度计仍可用于确定刚度趋势，经过培训。高估的刚度值可能是由于Myotest加速度计确定地面接触时间和飞行时间不准确，也可能是由于使用了假设质心运动具有谐波轮廓的方程式。