MOTIVATION AND EMOTION, cilt.44, sa.2, ss.190-208, 2020 (SSCI)
The main purpose of the current study was to investigate the explanatory mechanism of the drive for muscularity on the relations between frustrated basic needs and diverse indicators of muscle dysmorphia. To achieve this purpose, in the first place, as a pilot study needed to pursue the hypotheses of the main study, Basic Psychological Needs Satisfaction and Frustration Scale was adapted to Turkish and its psychometric properties were examined. In the main study, data were collected from 245 men with a mean age of 22.73 (SD = 3.86), who were engaged in regular bodybuilding activities. After the adaptation of Muscle Appearance Satisfaction Scale, the indirect predictive effects of frustrated basic needs on muscle dysmorphia symptoms through the drive for muscularity were examined via two structural equation models. Also, the moderating role of the drive for muscularity in the associations between each of the frustrated needs and muscle dysmorphia symptoms was tested via another structural equation model. Results revealed that (1) both the composite score of frustrated basic needs and frustrated relatedness are indirect predictors of all muscle dysmorphia symptoms through drive for muscularity and (2) drive for muscularity has a moderating role only in the relation between frustrated relatedness and muscle dissatisfaction (i.e., an indicator of muscle dysmorphia). These findings did not only support the assumptions of Self Determination Theory (SDT) indicating the link between frustrated needs and ill-being situations but also provided preliminary evidence for a new direction of SDT studies.