Objective: Increasing numbers of young Australian men are training and dieting to attain high muscle mass and low body fat and using steroids and performance and image enhancing drugs to expedite this process. This study explored men's identification with a muscularity-centred subculture and what contributes to the pursuit of masculine body image defined by muscularity. Method: Participants were 14 young men who (a) weight-trained >3 times per week, (b) used bodybuilding supplements daily, and (c) used/had used steroids/other performance and image enhancing drugs. Results: Interview analysis identified precipitating (e.g., low self-confidence), perpetuating (e.g., social media pressures), and resultant factors related to strict regime adherence, including simultaneous recreational drug use. This range of influences gives support to a sociocultural framework for explaining the development and maintenance of striving for a muscular ideal among this cohort. Conclusions: Understanding the factors contributing to the attainment of a muscularity-defined masculine body image is important given the risky health behaviours young men may engage in to reach this ideal.