The Validity and Reliability of the MyJump2 Application to Assess Vertical Jumps in Trained Junior Athletes

Abstract

This study aimed to assess the validity and reliability of jump assessments using the MyJump2 application. Eleven junior athletes (15 ± 1.4 years) performed five countermovement (CMJ) and drop jumps (DJ) measured simultaneously by a force platform and MyJump2. Additionally, intra- and inter-day reliability was assessed over two sessions, 7 days apart. Extremely high agreement between MyJump2 and the force platform (intra-class correlation coefficient, ICC ≥ 0.99) and the intra- and inter-operator agreement (ICC = 0.98–0.99) confirmed the validity and reliability of MyJump2. Mean typical errors (coefficient of variation percentage, CV%) within the first and second sessions were 4.9% and 4.5% respectively for CMJs, and 8.0% to 11.8% for DJ outcomes. CMJ height held acceptable inter-day reliability (CV < 10%; ICC > 0.8), while DJ did not. Results supported MyJump2 to be a valid and reliable tool for assessing jumps; however, with variability in DJs in this cohort, appropriate caution should be taken if including in a junior assessment battery.