Countermovement-Jump Test-Retest Reliability in Top-Level Para-Karate Athletes With Intellectual Impairment Using Kistler Force Plates

Abstract

This study investigated the test-retest reliability of the countermovement-jump (CMJ) test using Kistler force plates to assess explosive power in top-level para-karate athletes with intellectual impairment (II) or Down syndrome (DS). Forty-four athletes (II, n = 20; DS, n = 24) were evaluated during the 2023 World Karate Championships. Each performed two CMJs with a 1-min rest between. Key parameters measured included jump height, force index, and maximal rate of force development. Results showed no significant differences between test and retest for either group. Athletes with II exhibited better reliability metrics (e.g., intraclass correlation coefficient [ICC] = .381-.953) compared with DS (ICC = .029-.64). The study concludes that the CMJ test is highly reliable for assessing explosive power in athletes with II, while DS requires careful protocol adjustments to enhance reliability, ensuring consistent data for coaches and sport scientists.

Keywords: Down syndrome; disability sport; explosive power; jump height.