ABSTRACT

This study explored the influence of different take-off thresholds on the reliability and magnitude of countermovement jump (CMJ) performance variables. Twenty-three men were tested on two separate sessions. CMJ performance variables were obtained against three external loads (0.5–30-60 kg) using three take-off thresholds: 10 N (arbitrary value of 10 N), 5SD (mean value plus 5 standard deviations of the vertical force recorded during the flight phase), and PRF (peak difference between the vertical force trace and 0 N during the flight phase). No significant differences in reliability were observed between the three thresholds (CV and ICC values of one threshold were within 95% CI of the other thresholds). The magnitude of the variables generally differed between the 10 N threshold and the 5SD and PRF thresholds (P < .05), but not between the 5SD and PRF thresholds (P > .05). These results demonstrate that the take-off threshold influences the magnitude of CMJ performance variables but not their reliability.

摘要

本研究探讨了不同起飞阈值对反跳 (CMJ) 性能变量的可靠性和幅度的影响。23 名男性在两个不同的阶段接受了测试。CMJ 性能变量是使用三个起飞阈值针对三个外部负载（0.5-30-60 kg）获得的：10 N（10 N 的任意值）、5SD（平均值加上飞行期间记录的垂直力的 5 个标准偏差）阶段）和 PRF（飞行阶段垂直力轨迹与 0 N 之间的峰值差）。在三个阈值之间没有观察到可靠性的显着差异（一个阈值的 CV 和 ICC 值在其他阈值的 95% CI 内）。10 N 阈值与 5SD 和 PRF 阈值之间的变量大小通常不同（P< .05)，但不在 5SD 和 PRF 阈值之间 ( P > .05)。这些结果表明，起飞阈值影响 CMJ 性能变量的大小，但不影响其可靠性。