HOW TO CONTROL ANKLE JOINT IN VARIOUS DIRECTIONS OF ONE LEG JUMP-LANDING: FRONTAL PLANE MOMENT AND EMG STUDY

The variation of jump-landing directions would challenge muscular control around ankle joint. The purposes of this study were to assess the frontal plane moment of ankle and EMG of tibialis anterior (TA), peroneus longus (PL), and medial head of gastrocnemius (GAS) muscles. Eighteen male athletes participated in the study. Subjects performed the one leg jump-landing test from a 30 cm height platform in four directions; forward (0°), 30° diagonal, 60° diagonal, and lateral (90°) directions. The finding exhibited that peak evertor moment significantly increased from forward to lateral direction. The need for increased muscle activity of PL was highlighted. The landing needed more co-contraction between TA and PL for maintaining balance. It seems that the awareness around ankle during jump-landing in diagonal and lateral direction should be more focused comparing to forward direction