Effect of Training Modified FIFA 11+ on Kinematic Factors of Landing in Elite Handball Players

Warm-up programs are one of the most commonly used prevention programs in various sports. The most famous warmup training program is the FIFA 11+ for soccer which has been well researched in different sports. However, the mechanism of the effect of these exercises is still unclear, and this study examines the kinematic changes in landing after jumping by intervention of the modified FIFA 11+ program. In this semi-experimental study, 48 young and adult elite handball players were selected in the national league and randomly assigned into the equal training and control groups. The training group performed routine exercise and modified FIFA 11+, while the control group had only their routines exercises. Using the force plate and the Opti-Track camera, and the passive markers located on the landmarks of the body, by using MATLAB program, the trunk and knee flexion angles on the sagittal plane and the knee valgus angle on the frontal plate during the landing from the vertical jump at initial contact and whole landing time were analyzed. The modified 11+ training program had a significant effect on landing kinematic factors including increased flexion angle of the trunk and knee flexion and reduction of knee valgus angle in the training group. Comparing the two groups in post-test analysis, the flexion angles of the trunk and knee valgus angle were significantly different between the training group and the control group. The warm up and prevention program of FIFA 11+ with increase trunk flexion have an effect on lower limb muscle activation, resulting in more energy absorption and less force transmitted to the knee. By increasing the angle of knee flexion, reduces the shear forces and thus reduces pressure on the knee ligaments. Also, with the reduction of the valgus knee angle, the valgus load is reduced and all of these factors can be the cause of reducing the incidence and reduce the severity of injuries to the lower extremities, especially the knee.