Sha Zhanxin, Dai Boyi
School of Kinesiology and Nutrition, College of Education and Human Sciences, The University of Southern Mississippi, Hattiesburg, MS, USA.
Division of Kinesiology and Health, University of Wyoming, Laramie, WY, USA.
BMC Sports Sci Med Rehabil. 2021 Aug 30;13(1):103. doi: 10.1186/s13102-021-00330-z.
Previous studies have typically measured velocity and power parameters during the push-up, either using one or two force platforms. The purpose of the study was to compare the force, velocity, and power parameters between the one-force-platform method and the two-force-platform method during plyometric push-ups.
Thirty-four physically active young adults participated in the study to perform the plyometric push-up. For the two-force-platform calculation method, the forces applied to the feet and hands were both measured. For the one-force-platform calculation method, the forces applied to the feet were assumed to be constant, while the forces applied to hands were measured by one force platform. Whole-body linear velocities were calculated based on the impulse and momentum theorem. Whole-body power was calculated as the product of the whole-body forces and velocities.
The one-force-platform method overestimated the whole-body velocities and power compared with the two-force-platform method (1.39 ± 0.37 m/s vs. 0.90 ± 0.23 m/s, Cohen's d = 1.59, p < 0.05; 1.63 ± 0.47 W/body weight vs. 1.03 ± 0.29 W/body weight, Cohen's d = 1.49, p < 0.05). These differences were caused by the decreased forces applied to the feet compared to the initial value throughout most of the push-up phase. Large to perfect correlations (r = 0.55 - 0.99) were found for most variables between the two-force-platform and one-force-platform methods. Previous findings of push-up velocities and power using the two-force-platform and one-force-platform methods should be compared with caution. While the two-force-platform method is recommended, linear regression equations may be used to predict velocities and power parameters obtained from one force platform.
For those professionals who need to accurately quantify kinetic variables during the plyometric push-up, the two-force-platform method should be considered.
以往的研究通常在俯卧撑过程中测量速度和功率参数，使用一个或两个测力平台。本研究的目的是比较在增强式俯卧撑过程中，单测力平台法和双测力平台法之间的力、速度和功率参数。
34名身体活跃的年轻人参与本研究以进行增强式俯卧撑。对于双测力平台计算方法，测量施加在双脚和双手上的力。对于单测力平台计算方法，假定施加在双脚上的力恒定，而施加在双手上的力由一个测力平台测量。基于冲量和动量定理计算全身线性速度。全身功率计算为全身力与速度的乘积。
与双测力平台法相比，单测力平台法高估了全身速度和功率（1.39±0.37m/s对0.90±0.23m/s，Cohen's d=1.59，p<0.05；1.63±0.47W/体重对1.03±0.29W/体重，Cohen's d=1.49，p<0.05）。这些差异是由于在俯卧撑的大部分阶段，与初始值相比，施加在双脚上的力减小。双测力平台法和单测力平台法之间的大多数变量具有高度到完美的相关性（r=0.55-0.99）。使用双测力平台法和单测力平台法得出的俯卧撑速度和功率的先前研究结果应谨慎比较。虽然推荐使用双测力平台法，但线性回归方程可用于预测从一个测力平台获得的速度和功率参数。
对于那些需要在增强式俯卧撑过程中准确量化动力学变量的专业人员，应考虑使用双测力平台法。
