Comparison of lower limb muscle activation between the back and front leg during the forward jump in soccer

The goal of this study was to compare EMG activity between the back and front leg during the soccer head jump and landing. Football is one of the popular and high-risk sport. Non-contact anterior cruciate ligament (ACL) injuries often happen during the forward jump-landings in soccer. Two main parts of the forward head jump are jumping and landing. Usually, one leg locates front, and another leg locates back during jumping and landing phases. Twenty professional soccer players (۶۸.۳±۷.۵ kg, ۱۷۸±۵.۳ cm, ۲۷.۵±۴.۵ years) participated in this study. Ten Vicon motion captures (Vicon MX, Oxford, UK, ۲۰۰ Hz) were used to measure the kinematics variables. EMG activity in the rectus femoris, vastus lateral, vastus medial, tibialis anterior, gastrocnemius medial, gastrocnemius lateral, soleus, biceps femoris, and semitendinosus was recorded by the Myon wireless EMG system with a sampling frequency of ۱۰۰۰ Hz. EMG electrodes were located at an interelectrode distance of ۲۰ mm; one-use Ag/AgCl surface electrodes were attached to each muscle after shaving and cleaning of the skin with alcohol. Significant differences in muscle activation between the back and front leg were observed for vastus lateral, tibialis anterior, gastrocnemius lateral, soleus, and biceps femoris muscles. The vastus lateral and tibialis anterior muscles show higher muscle activation for the back leg compared to the front leg, while gastrocnemius lateral, soleus, and biceps femoris muscles show lower muscle activation for the front leg compared to the back leg. These findings suggest that back and front legs during soccer head jump employed various muscle activities for different muscles.