Abstract
While the FIFA 11 + Referees program (the 11 + Referees) is the only structured injury prevention program for referees, its effects on injury-related risk factors among referees remain underexplored. This study investigated the effects of the 11 + Referees on knee joint proprioception and dynamic balance. Thirty four female referees from the Tehran Premier Futsal League voluntarily participated and were randomly assigned to either a control group (n = 17) or the 11 + Referees group (n = 17). All participants underwent a baseline assessment including knee joint proprioception at angular velocities of 15°/s, 45°/s, and 60°/s, and position sense, as well as dynamic balance. Subsequently, the intervention group performed the 11 + Referees program three times weekly for 8 weeks, while the control group performed general warm-ups. Post-intervention, the same test battery was administered, and changes were analyzed to identify the program's effects on the measures understudied. Significant improvements were observed in knee joint proprioception at 15°/s (F = 18.19, p < 0.001, η²=0.44), 45°/s (F = 4.07, p = 0.056, ηp²=0.15), and 60°/s (F = 6.63, p = 0.017, η²=0.22) in the intervention group. However, dynamic balance did not show significant improvement (F = 0.79, p = 0.38, η²=0.033). In conclusion, an eight-week application of the 11 + Referees enhanced knee joint proprioception in female referees with large effect sizes, but had no significant effect on dynamic balance. Improvements in proprioception may be attributed to neuromuscular adaptations resulting from regular program use. The absence of balance improvement could be due to the short intervention period and the hard futsal court surface, which may limit the effectiveness of certain balance exercises. Future studies should explore the program's effects on other injury risk factors and injury rates.