This study aims to provide proof of the effectiveness of programs promoting physical activity, based on cognitive dissonance and normative focus theories which are designed to produce behavioral changes in persons with type 2 diabetes. Method Ninety-six type 2 persons with diabetes were assigned to one of three programs: a traditional information program, a norm-based program, and a dissonance-based program. The participants filled out a short French version of the International Physical Activity Questionnaire (IPAQ) one week before and one week after the program Results The results showed that the participants in the norm-based program made progress compared to those in the traditional information program. No significant difference was observed between the traditional information program and dissonance-based program. Conclusions These findings are consistent with both the focus normative theory and previous studies showing that recalling the norm increases compliance. The procedure to be used in diabetes prevention programs should focus on the normative dimensions of the desired behaviors in order to improve patients' quality of life.