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The purpose of this study was to determine if increased use of depth drop in strength and conditioning programs decreases ACL rupture risk factors. Injury rates for volleyball players are 4.21 injuries per 100 hours. The knee is the second most common injury site behind the ankle. The most common knee injury for female volleyball players are ACL injuries. (Migliorini et al., 2019). Female athletes are 2-10 times more likely to sustain ACL injuries than males. (Silvers & Mandelbaum, 2007). Jump landings are the most common non-contact ACL rupture mechanism. Collegiate women’s volleyball players, on average, jump between 40-220 times in a 5-set match. (Vlantes and Readdy, 2017). A 2D video analysis found participants ACL injuries showed increased knee valgus at ground contact when compared to uninjured groups. (Numata et al., 2017). Frontal view of knee valgus collapse can be seen by the decrease in knee distance. During knee flexion, tibial abduction and femur internal rotation occurs. (Quatmann & Hewett, 2014). Stiff landings, landing with minimal hip and knee flexion, increase shear force at the quadricep. This increases ACL loading, increasing injury risk. This can be seen through increased ground reaction forces. (Silvers & Mandelbaum, 2007). 400 N of quadriceps force can increase ACL strain by 3-5%. (Ueno et al., 2021). Increased Ground reaction forces can increase ACL strain by 33%. (Ueno et al., 2021)

Publication Date

Spring 2022


Boiling Springs, NC


Medicine and Health Sciences | Movement and Mind-Body Therapies | Rehabilitation and Therapy | Sports Sciences

Utilizing Depth Drop Training to Reduce ACL Rupture Risk Factors In Division I Collegiate Women's Volleyball Players