Reliability of My Jump 2 Derived from Crouching and Standing Observation Heights

Abstract

The crouching or prone-on-the-ground observation heights suggested by the My Jump app are not practical in some settings, so users usually hold smartphones in a standing posture. This study aimed to analyze the reliability of My Jump 2 from the standardized and standing positions. Two identical smartphones recorded 195 countermovement jump executions from 39 active adult athletes at heights 30 and 90 cm, which were randomly assessed by three experienced observers. The between-observer reliability was high for both observation heights separately (ICC~0.99; SEM~0.6 cm; CV~1.3%) with low systematic (0.1 cm) and random (±1.7 cm) errors. The within-observer reliability for the three observers comparing the standardized and standing positions was high (ICC~0.99; SEM~0.7 cm; CV~1.4%), showing errors of 0.3 ± 1.9 cm. Observer 2 was the least accurate out of the three, although reliability remained similar to the levels of agreement found in the literature. The reliability of the mean observations in each height also revealed high reliability (ICC = 0.993; SEM = 0.51 cm; CV = 1.05%, error 0.32 ± 1.4 cm). Therefore, the reliability in the standing position did not change with respect to the standardized position, so it can be regarded as an alternative method to using My Jump 2 with practical added benefits.

Validity and reliability of My Jump 2® app to measure the vertical jump on elite women beach volleyball players

“…The mean differences for jump height, flight time, and peak power were only 0.18 cm, 1.59 ms, and 9.76 w, respectively, showing no significant differences for these variables. The Bland-Altman plot also revealed mean differences inter-observers for jump height similar to studies conducted on a rigid surface ( Balsalobre-Fernández, Glaister & Lockey, 2015 ; Jimenez-Olmedo et al, 2022 ). However, it is noteworthy that a larger limit of agreement was found.…”

“…Also, different types of jumps and variables were investigated, including squat jumps, CMJ, drop jumps, flight time, jump height, and asymmetry index ( Haynes et al, 2019 ). Although the My Jump2 ® app consistently presented excellent values of reliability and validity when compared to force platforms and jump mats ( e.g ., Cruvinel-Cabral et al, 2018b ; Jimenez-Olmedo et al, 2022 ; Rago et al, 2018 ; Soler-Lopez et al, 2022 ), to date it was not found any scientific investigation that had tested the validity and reliability of the My Jump2 ® app to measuring jump height in sand surface. Furthermore, validity and reliability studies had focus in investigate males ( Carlos et al, 2015 ; Thomas et al, 2019 ).…”

The validity and reliability of the My Jump 2 app for measuring vertical stiffness in male college players

“…However, the height of the smartphone above the ground was not specified. In fact, it has been demonstrated that there is no significant difference in the results obtained from measurements taken at different heights above the ground when tested using the My jump2 app ( 33 ). Therefore, if a tripod is not available in a realistic measurement environment, it is feasible for the evaluator to conduct the test with a mobile phone in hand.…”

Reliability of ADR Jumping Photocell: Comparison of Beam Cut at Forefoot and Midfoot

“…However, the use of both technologies is usually limited to research or high-performance centers due to their high cost. Because of these high prices and given the demand by specialists to have tools that allow them to determine the vertical jump, numerous instruments have proliferated, which are more manageable and cheaper and which allow estimating the vertical jump in all types of populations and situations [10]. All these new instruments, such as accelerometers, jump 2 of 13 mats, or tailored video-based systems are more affordable alternatives than force platforms and motion capture systems.…”