Evidence for the construct validity of self-motivation as a correlate of exercise adherence in French older adults.

OBJECTIVES Exercise adherence involves a number of sociocognitive factors that influence the adoption and maintenance of regular physical activity. Among trait-like factors, self-motivation is believed to be a unique predictor of persistence during behavior change. The aim of this study was to validate the factor structure of a French version of the Self-Motivation Inventory (SMI) and to provide initial convergent and discriminant evidence for its construct validity as a correlate of exercise adherence. METHOD Four hundred seventy-one elderly were recruited and administered the SMI-10. Structural equation modeling tested the relation of SMI-10 scores with exercise adherence in a correlated network that included decisional balance and perceived quality of life. RESULTS Acceptable evidence was found to support the factor validity and measurement equivalence of the French version of the SMI-10. Moreover, self-motivation was related to exercise adherence independently of decisional balance and perceived quality of life, providing initial evidence for construct validity.