The Effect of the FIFA 11+ Warm-Up Program on Knee Instability and Motor Performance in Male Youth Soccer Players

This study aimed to investigate the effect of the FIFA 11+ program on knee instability and motor performance in male youth soccer players. Thirty male youth soccer players were divided into two groups: the experimental group (FIFA+) performed the FIFA 11+ program for 10 weeks, while the control group followed their usual warm-up routine. Dynamic knee valgus (DKV) and squat depth were assessed using a Microsoft Azure Kinect camera and dynaknee software. Maximal isometric muscle force was measured with a dynamometer. The Y Balance test was used to evaluate dynamic balance, while a countermovement jump test assessed lower limb power. The knee range of motion was measured with a goniometer, and the <i>t</i>-test was used to evaluate agility. After the intervention, the FIFA+ group showed a significant decrease in DKV and squat depth (<i>p</i> < 0.05), while the control group showed no significant changes (<i>p</i> > 0.05). Both groups improved in motor performance, with slight progress noted in the FIFA+ group. However, neither group demonstrated significant improvement in dynamic balance (<i>p</i> > 0.05). While the FIFA 11+ program may not substantially enhance overall motor performance or match the effectiveness of other training regimens, it shows potential for addressing biomechanical deficiencies and reducing the risk of injuries, particularly those related to dynamic knee valgus.