In the special subtext of this metaphoric scene (described in my notes below), the image of the exhausted dancers vividly evokes the toiling People, abused nearly to death, men and women alike, by the "dance" of willing exploitation. Note that at this image, Nostromo, who has just demonstrated his faithful service, has to "pull up," i.e., stop his forward movement, and even "pull up" meaning that he must try to raise the People's condition.