The effectiveness of an implementation intentions intervention for fruit and vegetable consumption as moderated by self-schema status.

Two experiments were conducted to determine whether self-schema status moderates the effectiveness of an implementation intentions intervention on nutrition behavior among university students not meeting relevant dietary guidelines. In Experiment 1, students were asked to eat at least 2 servings of fruit and 3 of vegetables daily for a week. Implementation intention condition participants listed what fruits and vegetables they would eat and when and where they would eat them; control condition participants did not. Among those who did not initially meet vegetable targets (n = 108), implementation intentions increased the vegetable consumption of healthy eater schematics, but not of nonschematics. There were no significant effects for fruit consumption among those initially not meeting fruit targets (n = 83). Experiment 2 replicated the moderating effect of healthy eater self-schema status in regard to the effectiveness of an implementation intentions intervention for vegetable consumption among undergraduates who were not initially eating at least 3 servings of vegetables daily (n = 62). Findings are discussed in regard to promoting healthy eating among university students, as well as the implementation intention, self-schema, and self-concordance literatures.

Test, revision, and cross-validation of the Physical Activity Self-Definition Model.

Structural equation modeling was used to test an extended version of the Kendzierski, Furr, and Schiavoni (1998) Physical Activity Self-Definition Model. A revised model using data from 622 runners fit the data well. Cross-validation indices supported the revised model, and this model also provided a good fit to data from 397 cyclists. Partial invariance was found across activities. In both samples, perceived commitment and perceived ability had direct effects on self-definition, and perceived wanting, perceived trying, and enjoyment had indirect effects. The contribution of perceived ability to self-definition did not differ across activities. Implications concerning the original model, indirect effects, skill salience, and the role of context in self-definition are discussed.