The adjective labored is used to describe something that is difficult or requires effort to perform. If you are pregnant with triplets by the ninth month your walking will be labored.
The adjective labored can describe something that is lacking natural ease or style. If you have to recite Shakespeare and you do so haltingly or self-consciously, then you have given a labored performance. If you then become really nervous and start to hyperventilate during a recitation of Hamlet's soliloquy, you will have labored breathing.