School of Sport, Exercise & Rehabilitation, Faculty of Health, University of Technology Sydney, New South Wales, Australia.
Connacht Rugby, Galway, Co. Galway, Ireland.
J Strength Cond Res. 2022 Nov 1;36(11):3159-3166. doi: 10.1519/JSC.0000000000004037. Epub 2021 May 5.
Howarth, DJ, Cohen, DD, McLean, BD, and Coutts, AJ. Establishing the noise: interday ecological reliability of countermovement jump variables in professional rugby union players. J Strength Cond Res 36(11): 3159-3166, 2022-The purpose of this study was to examine the interday "ecological" reliability of a wide range of ground reaction force-derived countermovement jump (CMJ) variables. Thirty-six male, professional rugby union players performed 3 CMJs on 4 separate days over an 8-day period during the first week of preseason. We calculated reliability for 86 CMJ variables across 5 interday combinations using 2 criteria: mean output across 3 jump trials (Mean 3 ) and single output from the highest jump (Best JH ). Interday coefficient of variation (CV) of the 86 variables in each CMJ phase, for Mean 3 and Best JH , respectively, ranged between concentric = 2-11% and 2-13%; eccentric = 1-45% and 1-107%; and landing = 4-32% and 6-45%. Mean 3 interday CV was lower in all 86 variables across every interday combination, compared with Best JH . CVs were lower in our cohort than previous studies, particularly for eccentric phase variables. There was no meaningful difference between interday conditions, suggesting any 2-day combination conducted within the first 8 days of preseason, represents a measure of "noise." We did not apply arbitrary reliability "cut-offs" used in previous work (e.g., CV <10%); therefore, our analysis provides reference reliability for a wide range of CMJ variables. However, we recommend that practitioners assess reliability in their athletes, as it is likely to be environment, protocol, and cohort specific.
豪沃思、DJ、科恩、DD、麦克莱恩、BD 和考茨、AJ。建立噪声：职业橄榄球联盟运动员反向跳跃变量的日内生态可靠性。J 力量与调理研究 36(11)：3159-3166，2022-本研究旨在研究广泛的地面反力衍生反向跳跃（CMJ）变量的日内“生态”可靠性。36 名男性职业橄榄球联盟运动员在 preseason 的第一周内的 8 天内分 4 天进行了 3 次 CMJ。我们使用 2 个标准计算了 5 个日内组合中 86 个 CMJ 变量的可靠性：3 次跳跃试验的平均输出（Mean 3）和最高跳跃的单个输出（Best JH）。在 Mean 3 和 Best JH 中，每个 CMJ 阶段的 86 个变量的日内变异系数（CV）分别为 2-11%和 2-13%；偏心=1-45%和 1-107%；和着陆=4-32%和 6-45%。与 Best JH 相比，所有 86 个变量在每个日内组合中的 Mean 3 日内 CV 均较低。CV 在我们的队列中低于以前的研究，特别是对于偏心阶段变量。在任何 2 天的组合中，日内条件之间没有明显的差异，这表明在 preseason 的前 8 天内进行的任何 2 天组合都代表了一种“噪声”的测量。我们没有应用以前工作中使用的任意可靠性“截止值”（例如，CV<10%）；因此，我们的分析为广泛的 CMJ 变量提供了参考可靠性。然而，我们建议从业者在他们的运动员中评估可靠性，因为它可能因环境、方案和队列而异。
