Cormie Prue, Deane Russell, McBride Jeffrey M
School of Exercise, Biomedical and Health Sciences, Edith Cowan University, Perth, Western Australia.
J Strength Cond Res. 2007 May;21(2):424-30. doi: 10.1519/R-19605.1.
The purpose of this study was to investigate the validity of power measurement techniques during the jump squat (JS) utilizing various combinations of a force plate and linear position transducer (LPT) devices. Nine men with at least 6 months of prior resistance training experience participated in this acute investigation. One repetition maximums (1RM) in the squat were determined, followed by JS testing under 2 loading conditions (30% of 1RM [JS30] and 90% of 1RM [JS90]). Three different techniques were used simultaneously in data collection: (a) 1 linear position transducer (1-LPT); (b) 1 linear position transducer and a force plate (1-LPT + FP); and (c) 2 linear position transducers and a force place (2-LPT + FP). Vertical velocity-, force-, and power-time curves were calculated for each lift using these methodologies and were compared. Peak force and peak power were overestimated by 1-LPT in both JS30 and JS90 compared with 2-LPT + FP and 1-LPT + FP (p <or= 0.05). Peak power determined by 2-LPT + FP was significantly higher than that determined by 1-LPT + FP under the JS90 loading condition. Peak vertical velocity determined by 2-LPT + FP was significantly lower than that determined by either 1-LPT and 1-LPT + FP in JS90. This investigation indicates that peak power and the timing of power output in the jump squat varies according to the measurement technique utilized. The 1-LPT methodology is not a valid means of determining power output in the jump squat. Furthermore, the 1-LPT + FP method may not accurately represent power output in free weight movements that involve a significant amount of horizontal motion.
本研究的目的是利用测力板和线性位置传感器（LPT）设备的各种组合，研究深蹲跳（JS）过程中功率测量技术的有效性。九名有至少6个月抗阻训练经验的男性参与了这项急性研究。先确定深蹲的一次重复最大值（1RM），然后在两种负荷条件下进行深蹲跳测试（1RM的30%[JS30]和1RM的90%[JS90]）。在数据收集过程中同时使用了三种不同的技术：（a）1个线性位置传感器（1-LPT）；（b）1个线性位置传感器和一个测力板（1-LPT+FP）；（c）2个线性位置传感器和一个测力板（2-LPT+FP）。使用这些方法计算每次举重的垂直速度、力和功率-时间曲线，并进行比较。与2-LPT+FP和1-LPT+FP相比，1-LPT在JS30和JS90中均高估了峰值力和峰值功率（p≤0.05）。在JS90负荷条件下，2-LPT+FP测定的峰值功率显著高于1-LPT+FP测定的峰值功率。在JS90中，2-LPT+FP测定的峰值垂直速度显著低于1-LPT和1-LPT+FP测定的峰值垂直速度。本研究表明，深蹲跳中的峰值功率和功率输出时机因所采用的测量技术而异。1-LPT方法不是确定深蹲跳中功率输出的有效方法。此外，1-LPT+FP方法可能无法准确代表涉及大量水平运动的自由重量运动中的功率输出。
