The opposite of "gotten shape" can be expressed using a variety of antonyms, depending on the context. If you are talking about physical fitness or body shape, antonyms might include "out of shape," "unfit," "flabby," or "untoned." If you are talking about the shape or condition of something else, antonyms might include "misshapen," "distorted," "disfigured," "broken," or "ruined." In general, any word that suggests the opposite of "getting into shape" or "improving" would be a possible antonym. It is important to consider the context in order to choose the most appropriate antonym for the situation.