The measurement of exercise motives: Factorial validity and invariance across gender of a revised Exercise Motivations Inventory

Objectives: The aim of this study was to further develop and refine the Exercise Motivations Inventory (EMI), a measure of individuals’ reasons for exercising. Design: Confirmatory factor analytic procedures using LISREL were employed to test the hypothesised fourteen factor structure of the revised instrument (the EMI-2) and the invariance of the factor structure across gender. Methods: 425 civil servants completed the revised instrument. Analyses were conducted in three phases. Phase One involved detailed examination of the fit of the fourteen factors separately in order to detect and eliminate poor indicators. In Phase Two each factor was paired with every other factor in order to detect and eliminate ambiguous items. In Phase Three factors were grouped with conceptually related factors into five submodels and the fit and factorial invariance across gender of these submodels was tested. Results: Item elimination at Phases One and Two led to the development of a set of internally consistent factors with strong indicators and good discriminant validity. Phase Three gave further evidence for the convergent and discriminant validity of the items and factors and strong support for the invariance of the factor structure across gender. Conclusions: The EMI-2 is a factorially valid means of assessing a broad range of exercise participation motives in adult males and females, applicable to both exercisers and non-exercisers.