This study aimed at further investigating factors associated with drive for muscularity in weight-training men, using a biopsychosocial model as a frame. Our current findings confirmed most of the hypothesized factors as being associated with global drive for muscularity and muscularity-related attitudes and behaviors. Internalization of media body ideals presented the highest predictive value for drive for muscularity. This indicates that the drive for muscularity, similar to the drive for thinness in women, seems to be a problem of societies in which highly unrealistic body ideals are advertised and idealized. As a consequence, education on, and advertisement of, body ideals based on health and well-being, instead of thinness or leanness and muscularity, should be pursued in order to promote health instead of appearance.