Kinetics and EMG analysis of double - legged landing among Reserve Officer Training Unit (ROTU) trainee

Abstract

During landing, the double - legged landing strategy is preferred as it provides stability and minimizes injury risk in various activities that involve different magnitudes of ground reaction force (GRF). Factors such as height, load and landing types during double - legged landing contribute to the injuries of ROTU trainee during military activities. This study compares knee flexion angle, maximum knee flexion angle, peak vertical ground reaction forces and muscle activity. In this study, 14 subjects (7 males and 7 females) with normal body mass index and no history of ACL injuries involved. Firstly, they performed different types of double-legged landing with constant height 40cm, follow with different heights of 20-60cm with constant double-legged landing and lastly different load (1kg and 2kg) will apply on their leg with constant height and landing type. Force plate and motion-capture system are used to capture kinetic data, while Myomonitor is used to analyze muscle activity. As a result, soft landing style is the best way of landing since it exhibits the lowest peak GRF and higher knee flexion angles compare to other landing. The knee flexion angle at initial contact, the maximum knee flexion and peak GRF increase with the increment of landing height. Males show a higher peak GRF and knee flexion angle during the increment of landing height and load compare than females. Moreover, the use of muscle is higher in females compare than males during the increment of load and landing heights.