Knee abduction and hip adduction during functional tasks may indicate increased joint injury risk and discriminate between pathological and healthy people. Muscles’ neuromuscular variables such as amplitude (EMG_AMP) and onset (EMG_ONSET) have been used to explain kinematics. The study aimed to evaluate the correlation between two EMG variables of seven trunk and lower limb muscles and 3D kinematics during two tasks. Eighteen physically-active women participated in the study. The following variables were obtained during single-leg squat and anterior step-down: (i) EMG_AMP and EMG_ONSET of fibularis longus (FL), tibialis anterior (TA), vastus medialis (VM), biceps femoris (BF), gluteus medius (GMED), ipsilateral (OB_IL) and contralateral (OB_CL) external obliques and (ii) knee abduction and hip adduction angular displacement (initial angle – angle at 60° of knee flexion). Spearman’s correlation coefficient was calculated between kinematic and EMG variables. Greater knee abduction was correlated with delayed TA_ONSET, GMED_ONSET and OB_IL_ONSET during step-down. Greater hip adduction was correlated with lower VM_AMP, BF_AMP and delayed VM_ONSET during step-down. Although task-specific, these results suggest that EMG_ONSET may influence knee abduction, while both EMG_ONSET and EMG_AMP may affect hip adduction. The identification of muscle activation patterns in relation to kinematics may help the development of injury prevention and rehabilitation programs.

功能性任务期间的膝外展和髋内收可能表明关节损伤风险增加，并区分病态人群和健康人群。肌肉的神经肌肉变量，例如振幅 (EMG _AMP ) 和起始时间 (EMG _ONSET ) 已被用来解释运动学。该研究旨在评估两项任务期间七个躯干和下肢肌肉的两个 EMG 变量与 3D 运动学之间的相关性。十八名经常锻炼身体的女性参与了这项研究。在单腿深蹲和前降过程中获得以下变量：（i）腓骨长肌（FL）、胫骨前肌（TA）、股内侧肌（VM）、股二头肌（BF）、臀肌的肌电图 AMP 和_肌电图开始正中肌 (GMED)、同侧 (OB_IL) 和对侧 (OB_CL) 外斜肌以及 (ii) 膝关节外展和髋关节内收角位移（初始角度 - 膝关节屈曲 60° 时的角度）。计算运动学变量和肌电图变量之间的斯皮尔曼相关系数。更大的膝外展与降压过程中延迟的 TA _ONSET、GMED _ONSET和 OB_IL _ONSET相关。_{更大的髋内收与较低的 VM AMP}、BF _AMP和降压过程中延迟的 VM _ONSET相关。尽管针对具体任务，这些结果表明 EMG _ONSET可能会影响膝关节外展，而 EMG _ONSET和 EMG _AMP都可能影响髋关节内收。识别与运动学相关的肌肉激活模式可能有助于制定损伤预防和康复计划。