Impulsive loading by the ground reaction force (GRF) around heelstrike during walking is closely related to joint degeneration and might be affected by joint movement of the locomotor system. Fifteen healthy males (age: 25.5 ±3 years) were studied to investigate the association between the quantitative joint angles, angular velocities and accelerations of the lower-limb joints, and the loading rates of the GRF. Apart from the gait speed, both the ipsilateral kinematics during the swing phase, and the contralateral kinematics around the beginning of the terminal double limb stance (DLS), may significantly contribute to the heelstrike and maximum loading rates of the GRF. The magnitude of the heelstrike impulsive GRF was particularly affected by the peak ankle dorsiflexion velocity during the swing phase of the ipsilateral limb. However, for generating the maximum loading rate of nearly eight times the magnitude of that of the heelstrike one needed more kinematic variables to be modulated in advance, especially the knee flexion velocities around the beginning of the terminal DLS of the contralateral limb. Knowledge of the joint mechanics of the locomotor system for controlling the magnitude of the impulsive GRF during normal walking might be helpful for gait retraining for the elderly or patients who might have excessive impulsive GRF and a high risk of joint degeneration.