Author(s): HSUEH, Y.H., CHANG, H.Y., HUANG H.L., CHEN H.H., LIN, P.C., Institution: NATIONAL YUNLIN UNIVERSITY OF SCIENCE AND TECHNOLOGY, Country: TAIWAN, Abstract-ID: 1525

INTRODUCTION:
The Landing Error Scoring System (LESS) is a tool used in sports medicine and biomechanics to assess the quality of movement during landing tasks, particularly in activities such as jumping and cutting motions. LESS evaluates several key components of landing technique, including body position, foot placement, and joint movement, to assign a numerical score indicative of the quality of the landing. The system typically involves video recording a participant performing a series of standardized landing tasks, which are then reviewed and scored based on predefined criteria. However, this system assessed the video recording by using a manual method, instead of an automatic method. Researchers need to spend a lot of time dealing with those recorded videos to assess the jump-landing movements. The purpose of this study was to use an automatic image tracking and recognition method to assess jump-landing movement and track joint angle when participants performed Landing Error Scoring System Scoring.
METHODS:
Twenty-six collegiate athletes (10 women and 16 men, age 20.4 ± 0.72 years, height 169.5 ± 7.9 cm, weight 65.4 ± 9.7 kg) performed 3 jump-landing trials that were recorded by 2 web cameras (Logitech C920 Full HD Pro webcam) in the front and lateral side of the participates. For the jump-landing assessment, participants jumped from a 30-cm-tall box to a designated area in front of the box. We instructed them to complete a maximal vertical jump immediately after landing in the designated area. The web cameras were controlled by a laptop computer with a self-written joint angle tracking software (written with Labview VISION module). The values obtained from 3 trials were averaged to obtain a participant’s LESS score. After data collection, one researcher (H.Y.C.) evaluated the recorded video data and scored the LESS. The participants according to their LESS scores divided into the Good group (LESS score ≦5) and the Poor group (LESS score >5). The independent T-test was used to compare the joint angle differences in each item of the LESS assessment (17 items). Significance was set at P < .05.
RESULTS:
The results indicated that significantly better LESS score for the Good group (3.92±0.9) than the Poor group (6.6±1.0) (p=.00); Among the joint angle, the mean hip angle in maximum knee flexion (p=.011), hip joint displacement (p=.02), mean maximum knee flexion angle (p=.025), knee joint displacement (p= .018), and the hip joint displacement greater than 45 degrees in the maximum knee flexion (p=.001) were reached a significant difference, and the rest of the items did not reach a significant difference. In total, the joint angles in the Good group were better than those of the Poor group.
CONCLUSION:
The Good group had better joint angle and displacement than the Poor group. The automatic image tracking and recognition method to assess jump-landing movement and track joint angle when participants performed Landing Error Scoring System Scoring could spend less time dealing with data.