###### Abstract  
This randomized control study aimed to assess 12 weeks of a novel neuromuscular training program (KneeRugbyWomen) on jump-related biomechanical variables in amateur female rugby players. Twenty-four participants were randomly allocated to either an experimental group (EG; \(n=12\), age: 20.05 \(\pm\) 4.43 yrs., height: 166.54 \(\pm\) 4.46 cm, weight: 64.65 \(\pm\) 6.44 kg) or a control group (CG; \(n=12\), age: 20.04 \(\pm\) 4.88 yrs., height: 166.83 \(\pm\) 7.30 cm, weight: 69.83 \(\pm\) 12.84 kg). Participants were tested before and after a 12-week intervention for jump-related biomechanical variables (leg stiffness, Reactive Strength Index (RSI), and landing mechanics using the Landing Error Scoring System (LESS)). A significant increase in RSI was found in EG (\(p=0.012\), r = 0.70, large effect). At post-testing, players in EG had significantly greater RSI scores compared to CG at post-intervention (\(p=0.007\), r = 0.55, large effect). LESS scores of CG were significantly greater compared to EG at pre-intervention (\(p=0.008\), r = 0.55, large effect) and post-intervention (\(p=0.003\), r = 0.60, large effect). Results of this study demonstrate a positive effect of the KneeRugbyWomen training program on RSI, which has been previously associated with increased ACL injury risk in female players. Keywords:injury prevention; jumping; risk factors; injury; anterior cruciate ligament +
Footnote †: journal: Medical  
measure of SSC capability [17]. It is considered an indicator of ACL injury risk [18], and it is suggested that low RSI values indicate poor SSC function [19] and further discriminate between playing abilities, as elite players have more effective contact times than non-elite players [20]. SSC efficiency can also be assessed by means of leg stiffness, with greater values of leg stiffness demonstrating an increased ability of the dynamic mechanisms to generate rebound movements during the SSC [21] and reduce the load on the ACL [12]. Further, there is evidence to support that females have both lower values of absolute leg stiffness (ALS) [22; 23] and RSI [24; 25] compared to male athletes, supporting the rationale for the increased risk of injury in this population. Effective landing biomechanics help reduce mechanical forces on the knee, specifically reducing the load on the ACL, decreasing the risk of injury [26]. The ankle, knee, hip, and trunk cooperate to absorb force on landing [27], with soft landings being more effective in absorbing greater mechanical forces as they are accompanied by higher angles of hip, knee, and ankle flexion compared to stiff landing [28]. Moreover, a knee flexion angle lower than 30\({}^{\circ}\) increases tension on the ACL [9], increasing non-contact injury risk. Compared to males, typically, we see greater evidence of dynamic knee valgus in females [27; 29] with a contralateral pelvic drop, internal femoral rotation, knee valgus, tibia internal rotation and foot pronation. A widely utilized and valid diagnostic tool for assessing injury risk during landing is the Landing Error Scoring System (LESS) [30]. The test has good levels of reliability in the field and has detected individuals at greater risk of non-contact ACL injury during landing tasks [31]. Recent evidence has demonstrated that high-quality prevention programs [11] can reduce non-contact knee injuries by up to half [32; 33]. Effective prevention programs in both male and female athletes often include static and dynamic balance, strength and power development of the lower limbs and pylemetric activities [34; 35; 36; 37; 14; 32]. This has subsequently been confirmed in a recent systematic review [38] stating that it is appropriate to combine balance, strength and pylemetrics for a more effective prevention program. However, a comprehensive prevention program should also focus on the landing skills of the athlete, especially in female team sports [39; 31; 40].