Exploration of Drive for Leanness in Relation to Drives for Thinness and Muscularity, as well as their Concurrent Associations with Health-Related Outcomes

Drive for leanness, the motivation to build lean muscle,as well as obtain low enough body fat content for this muscle to be seen, is a nascent drive construct compared to the more established drives for thinness and muscularity. What little research has been done on drive for leanness has suggested that drive for leanness is more sex neutral, as well as potentially more adaptive,than the other drive variables. However, there is debate regarding the factor structure of drive for leanness, or more specifically,whether drive for leanness is its own unique construct or if it is better described as an amalgamation of drives for thinness and muscularity. This study aimed to extend the drive for leanness literature in four ways: 1) create a modified Drive for Leanness Scale more semantically similar to the other drive measures; 2) determine if drive for leanness is best described as a unique construct; 3) discern if drive for leanness is best described as an amalgamation of drives for thinness and muscularity; and 4) explore associations between drive for leanness and broad disordered eating-and health-related outcomes. The Modified Drive for Leanness Scale (M-DLS) evidenced good preliminary psychometric properties. Analyses of the factor structure of drive for leanness did not support the uniqueness nor the amalgamated hypothesis. Rather, drive for muscularity overlapped onto drive for leanness, while drive for thinness remained distinct. Finally, the overlapping drive for leanness/muscularity latent variable predicted more negative health-related outcomes than observed drive for leanness has in the past. This study adds to the literature by broadening what is known about the factor structure of drive for leanness in relation to the other drives, providing a base for future drive for leanness model building and outcome associative wor