When a player raises or lowers his weapon while moving in any direction, the character will continue to move in that direction for a few steps and the player cannot stop this movement.
This occurs while crouching and standing, when moving forward, sideways or backwards, while walking, running and during combat pace with either the main weapon or the sidearm.
Every time the "raise/lower weapon" action is used a few more seconds of forced movement are queued and the players is unable interrupt it except when pressing the "Step over" key (standard "v").