Non-contact lower extremity injuries, particularly anterior cruciate ligament (ACL) injuries, are among the most common and debilitating injuries in female futsal players. Jumping and landing tasks accompanied by sudden deceleration and directional changes play a major role in the occurrence of these injuries. In this regard, leg stiffness, the hamstring-to-quadriceps strength ratio, and neuromuscular activation patterns are considered key factors influencing dynamic knee stability and injury risk. The purpose of the present study is to investigate the association between leg stiffness and the hamstring-to-quadriceps strength ratio and electromyographic activity during different jump–landing tasks (single-leg landing, double-leg landing, and stop-jump) in female futsal players. This study adopts a descriptive–analytical (correlational) design and will be conducted on 20 healthy female futsal players with at least three years of regular training experience. Leg stiffness will be calculated using ground reaction force data obtained from a force plate combined with video-based motion analysis. Isometric strength of the hamstring and quadriceps muscles will be assessed using a handheld dynamometer, and electromyographic activity will be recorded using surface electromyography. It is expected that the findings of this study will provide a more comprehensive understanding of the interaction between biomechanical and neuromuscular factors related to injury risk and contribute to the development of targeted training and injury prevention programs for female futsal players.