Can I Make an Animation Disregard Physics?

I am trying to create an animation that contains a keyframe where the player's entire body is lowered into the ground (or whatever they are standing on). I did this by simply changing the LowerTorso's position for that keyframe. When testing it in the animation editor, it looks great and the dummy goes into the ground, but when actually testing it in-game, it seems as if the animation refuses to let my character go into the floor. Is this due to physics or something? Is there a way to avoid this issue? Many thanks in advance.