Motivation Questionnaire to Adopt a Healthy Lifestyle: Adaptation of the Treatment Self-Regulation Questionnaire

The purpose of this study was to develop a Motivation Questionnaire to Adopt a Healthy Lifestyle (CM-EVS) for adolescents, an adaptation of the Treatment Self-Regulation Questionnaire (TSRQ) to the Spanish context. Two independent studies were carried out, in 858 and 344 post-compulsory secondary education students (aged from 16 to 21) participated, respectively. The factorial structure of the instrument was tested in the first study. Results showed unsuitable fit indices because of item ten. After a new wording of this item, results gave support to a four-subscale structure (self-determined motivation, introjected regulation, external regulation, and amotivation). There was invariance across sex and physical exercise. Except for introjected regulation, internal consistence (Cronbach’s alpha and composite reliability) of the rest of subscales was acceptable (> .70). Results showed evidence of reliability and validity of the TSRQ in order to measure motivation to adopt a healthy lifestyle in Spanish adolescents.