Are proximal and distal neuromuscular parameters able to predict hip and knee frontal plane kinematics during single-leg landing?

OBJECTIVE:To determine if proximal and distal neuromuscular parameters (EMG amplitude and median frequency - MDF) can predict frontal plane kinematics during single-leg landing. STUDY DESIGN:Cross sectional study. SETTING:Laboratory. PARTICIPANTS:Fifteen participants (7 female) performed six single-leg landings with measures of frontal plane kinematics and EMG obtained 230 ms after first foot contact, totalizing 90 landings. MAIN OUTCOME MEASURES:(i) 2D hip adduction [hip ADD] and knee frontal plane projection angle [knee FPPA]; (ii) EMG amplitude and MDF of gluteus medius [GMed], tensor fascia latae [TFL], peroneus longus [PL] and tibialis anterior [TA]. RESULTS:We observed that MDF of TA was a significant predictor of hip ADD (p = 0.037; β = -0.049 Hz; R2c = 0.30). Also, MDF of PL was significant predictor of knee FPPA (p = 0.043; β = 0.042 Hz; R2c = 0.37). Hip muscles and EMG amplitude parameters were not considered predictors of frontal plane kinematics. CONCLUSION:The firing frequency of ankle muscles predicted the variance of hip and knee frontal plane kinematics during single-leg landing.