Between Days Reliability of 2D Video Analysis during Landing while Undertaking a Crossover Hop Test

Abstract

The Crossover Hop Test is a Functional Performance Test (FPT), which is used to demonstrate the leg muscles strength and performance, and evaluate symmetry between lower limbs, while evaluating the hop distance. Hop tests have been shown to be reliable for both injured and active subjects. The current study aims to establish the between days reliability of 2-Dimensional (2D) video analysis measuring knee valgus angles (frontal plane projection angle; FPPA) during each landing whilst undertaking a crossover hop test. Nine recreational male athletes (age 33.89 ± 3.96, height 170 ± 8.59 cm, weight 86.94 ± 20.86 kg) participated in the experiment. Each individual performed three repetitions of the cross over hop test, for both legs, and then repeated the same test seven days later. Results showed from the four landings that the first and third, for both legs demonstrated excellent Intraclass Correlation Coefficient (ICC) values for FPPA between days, while good to excellent ICC values for FPPA of the second landing and moderate ICC values for FPPA for the fourth. Standard Error Measurement (SEM) scores ranged from 1.04° to 2.42° for the right FPPA during the four landings, while the range of SEM values for the left FPPA were from 0.82° to 2.08°. The landing strategy adopted by participants, as defined by FPPA, would appear to be consistent between sessions. Hence, researchers and clinicians will be able to use crossover hop tests, which incorporate 2D video analysis, to assess simultaneously the limbs' performance functionality and the valgus angle of the knee. Therefore, this will save the athletes' and researchers' time, which will subsequently reduce the amount of fatigue resulting from over testing.