You have to specify that the object's z value is changing. This uses the return and right shift key to do that.
Code:
vizact.whilekeydown(viz.KEY_RETURN,hand.translate,0,0,vizact.elapsed(1),viz.RELATIVE_WORLD)
vizact.whilekeydown(viz.KEY_SHIFT_R,hand.translate,0,0,vizact.elapsed(-1),viz.RELATIVE_WORLD)