Background: Anterior cruciate ligament (ACL) injuries are a major concern in female soccer players, with change of direction (COD) movements being a key contributor to non-contact injuries. Traditional injury prevention programs have shown limited effectiveness in addressing individual biomechanical deficits. This study aimed to evaluate the effects of a 10-week unilateral strength training program on COD mechanics and ACL injury risk factors. Methods: Eleven female soccer players participated in a pre–post intervention study. Movement mechanics was assessed using the Cutting Movement Assessment Score (CMAS) at 45°, 75°, and 90° angles. The training program included unilateral lower limb strengthening exercises designed to enhance neuromuscular control and reduce biomechanical risk factors. Risk profiles were analyzed before and after the intervention. Statistical analyses included paired t-tests and effect size calculations. Results: Significant improvements in CMAS scores were observed at all COD angles (p < 0.05), with the largest effect at 90° (Cohen’s d = 2.1). The percentage of high-risk players decreased from 82% to 0%, while the proportion of low-risk players increased from 36% to 73%. Improved knee alignment, foot placement, and trunk stability were key contributors to the observed movement enhancements. Conclusions: Unilateral strength training may effectively improve COD mechanics and reduces biomechanical risk factors associated with ACL injuries in female soccer players. Our findings suggest that individualized training interventions can influence current injury prevention strategies.

(1) Background: Shoulder pathologies are mostly found in overhead sports. Many risk factors have been identified, in particular a deficit in the kinetic chain. The aim of this review was to find out whether prevention by strengthening the kinetic chain can have an impact on the rate of shoulder injury in overhead pitching athletes. (2) Methods: A systematic review of the literature was carried out, including studies on the role of the kinetic chain in the prevention of overhead athletes. The studies used were works published over the last 10 years searched on PubMed, Cochrane Library, PEDro and Science Direct. They were also analyzed by methodological quality scales: the PEDro scale and the Newcastle–Ottawa scale. (3) Results: Eight studies met the inclusion criteria. The studies analyzed revealed a significant correlation between the use of the kinetic chain and the prevention of shoulder injuries, associating factors such as muscle strength, physical performance in tests (CMJ, FMS), static and dynamic balance and the ability to transfer energy from the lower to the upper body. (4) Conclusions: It is important to integrate core stability work and lower limb strengthening to minimize excessive stress on the shoulder complex, while optimizing force production and performance.

Purpose: Anterior cruciate ligament reconstruction (ACLR) using the hamstring graft is commonly performed to restore knee stability; however, it induces significant neuromuscular and biomechanical changes, particularly in the hamstring. This study aimed to evaluate the changes in maximum effective angle, hamstring strength, and hamstring-to-quadriceps (H/Q) strength ratio at 3 and 6 months post-ACLR and compare these outcomes to a control group. Methods: This prospective controlled study included 20 ACLR patients and 20 age- and gender-matched controls. Hamstring peak torque, maximum effective angle (MEA), and the H/Q ratio were assessed using isokinetic dynamometry at 60°/s. The ACLR group was evaluated postoperatively at 3 and 6 months, while the control group underwent a single evaluation. Results: At 3 and 6 months, the ACLR group exhibited significantly lower MEA (26.3° ± 8.2 and 28.2° ± 9.4) compared to the control group (36.4° ± 12.0; p < 0.01). Hamstring peak torque and H/Q ratios were also lower in the ACLR group but showed slight improvements over time. The H/Q ratio increased significantly between 3 and 6 months (51% to 56%; p = 0.041). Conclusion: The use of hamstring graft in ACLR leads to persistent MEA and strength deficits despite rehabilitation. Advanced, targeted rehabilitation protocols are essential to address these deficits, optimize recovery, and reduce the risk of reinjury.

Anterior cruciate ligament reconstruction (ACL-R) significantly affects lower limb biomechanics, particularly during dynamic movements like jumping. The countermovement jump (CMJ) is a commonly used test to evaluate force production and asymmetry in post-ACL-R individuals. This study aimed to compare eccentric and concentric forces during the CMJ between ACL-R patients and healthy controls. This retrospective study included 56 ACL-R patients and 47 recreational athletes. All participants performed CMJs on a dual force plate to measure eccentric mean force (ECC), Concentric mean force (CON), and limb symmetry index (LSI). A mixed ANOVA was performed to compare ECC LSI and CON LSI between the ACL-R and control groups. CMJ height was significantly lower in the ACL-R group compared to the control group (-25.4%, p < 0.001), with a lower ECC LSI (-7.7%, p < 0.001) and CON LSI (-10.0%, p < 0.001). Six months after ACL-R, both eccentric and concentric force production remain compromised, with significant inter-limb asymmetries. These findings highlight the need for targeted rehabilitation strategies to restore force symmetry and optimize return-to-sport readiness.

"Physical Activity for Health Promotion and Disease Prevention in Africa and Cameroon: A Call to Action" published on 20 May 2023 by Human Kinetics.