There is a persistent need in sport science for developing a measuring tool that is affordable, portable, and easy to use. We aimed to examine the concurrent validity and test–retest reliability of the My Jump 2 app compared to a validated OptoJump instrument for measuring jump performance during the squat jump (SJ), countermovement jump (CMJ), and CMJ free arms (CMJAM) in primary school children. A total of 48 participants (11–14 years age), volunteered to participate in this research. The jumps were recorded with a validated OptoJump photoelectric cell system and a concurrent device (iPhone X through My Jump 2 app) at the same time. The participants repeated the testing procedure after two weeks to assess the reliability of the measurements (ICC). Systematic bias between sessions and tools was evaluated using the paired samples t-test and Bland and Altman analysis. High test–retest reliability (ICC > 0.89) was observed for all measures’ in-between conditions. Very large correlations in the total sample were observed between the My Jump 2 app and OptoJump for SJ (r = 0.97, p = 0.001), CMJ (r = 0.97, p = 0.001), and CMJAM (r = 0.99, p = 0.001). Bland and Altman’s plot depicting limits of agreement for the total sample between the OptoJump and My Jump 2 show that the majority of data points are within the 95% CIs. The results of this study suggest that My Jump 2 is a valid, reliable, and useful tool for measuring jump performance in primary school children.

中文翻译：

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我的Jump 2应用程序在测量小学生垂直跳跃方面的有效性，可靠性和实用性。

运动科学一直需要开发一种价格合理，便携且易于使用的测量工具。我们的目的是与经过验证的OptoJump仪器相比，检查My Jump 2应用程序的并发有效性和重测可靠性，该仪器用于测量深蹲（SJ），背向运动（CMJ）和CMJ自由臂（CMJAM）期间的跳跃性能。小学生。共有48位参与者（11-14岁）自愿参加了这项研究。使用经过验证的OptoJump光电电池系统和并发设备（通过My Jump 2应用程序进行的iPhone X）同时记录跳跃。参与者在两周后重复测试程序以评估测量的可靠性（ICC）。使用配对样本评估了会话和工具之间的系统偏差t检验以及Bland和Altman分析。在所有条件之间，所有测试的重测信度都很高（ICC> 0.89）。在My Jump 2应用和OptoJump的SJ（r = 0.97，p = 0.001），CMJ（r = 0.97，p = 0.001）和CMJAM（r = 0.99，p = 0.001 ）的总样本中观察到非常大的相关性）。布兰德（Bland）和奥特曼（Altman）的图描述了OptoJump和My Jump 2之间的总样本一致度极限，这表明大多数数据点都在95％置信区间内。这项研究的结果表明，我的跳跃2是衡量小学生跳跃表现的有效，可靠和有用的工具。