Helping middle-aged women translate physical activity intentions into action: Combining the theory of planned behavior and implementation intentions

The current experiment examined whether women with implementation intentions show greater correspondence between their exercise intentions and behaviors, exercise more frequently, and show changes over time in measures of theory of planned behavior (TPB) constructs and scheduling self-efficacy relative to a control group. Participants were 47 women randomly allocated to an implementation intentions or control condition. Measures of TPB constructs and scheduling self-efficacy were assessed at baseline and 8 weeks later. Regression analyses showed that intentions were a significant predictor of behavior for women in the experimental condition (p<.01). A significant Condition x Time interaction was found for scheduling efficacy (p<.03) and a nonsignificant interaction was found for perceived behavioral control (p = .06), indicating that only the experimental group increased scheduling self-efficacy and perceived behavioral control. No significant group differences were found for the other TPB constructs or self-reported exercise.