Measurement of exercise dependence in bodybuilders

Objective. The purpose of this study was to explore exercise dependence in bodybuilders, and undertake preliminary validation of a measurement instrument. Experimental design. A comparative analysis of self-report indices between groups. Participants. Forty-seven bodybuilders, 31 individuals who weight trained for general fitness purposes and 24 weightlifters participated in the study. Measures. Each subject completed the following: demographic information, bodybuilding-specific versions of the social identity and exclusivity scales of the Athletic Identity Measurement Scale, the physical strength and body attractiveness subscales of the Physical Self-Perception Profile, a short form of the Marlowe-Crowne Social Desirability Scale, and a 9-item Bodybuilding Dependence Scale. Results. Factor analysis on the BDS revealed 3 subscales (social dependency, training dependency and mastery) which accounted for 68.4% of the variance. Internal consistency was satisfactory for each subscale (Chronbach's α=0.76, 0.75 and 0.78 respectively). The BDS social dependency and PSPP body attractiveness scores of the bodybuilders were higher than those of the weightlifters, whose scores were higher than those of the fitness trainers. The bodybuilders scored higher on both AIMS subscales than the other groups. The bodybuilders and weightlifters scored higher on PSPP physical strength than the fitness trainers. BDS social dependency correlated with both AIMS and both PSPP subscales, and BDS training dependency correlated with AlMS exclusivity. All three BDS subscales correlated with training frequency. Discriminant analysis found the combination of AIMS social identity, BDS social dependency and years training experience enabled correct classification of 92% of the respondents. Conclusions. These results support the construct and concurrent validity of the BDS social dependency subscale, but do not wholly support the validity of the other two subscales.