Exploring Factors Influencing Regular Exercise Intention in High School Females: An Empirical Study Based on the Theory of Planned Behavior

Promoting regular exercise among adolescent females is a critical public health objective. This study advances the Theory of Planned Behavior (TPB) by integrating “past behavior” as a key external variable to explore the determinants of exercise intention among high school females in Taiwan. Employing a convenience sampling method, we collected 392 valid questionnaires from senior and vocational high school students. Structural equation modeling results revealed that past behavior significantly predicted both attitude (β = .339, p < .001) and perceived behavioral control (β = .537, p < .001). In turn, attitude (β = .385, p < .001) and perceived behavioral control (β = .326, p < .001) were strong predictors of exercise intention. Notably, subjective norm did not directly influence intention (β = .066, p > .05). This study confirms the enhanced predictive power of the extended TPB model and provides a key theoretical contribution by demonstrating the pivotal mediating roles of attitude and perceived control. Practically, the findings suggest that interventions should focus on fostering positive initial exercise experiences and enhancing self-efficacy to effectively promote sustained physical activity in this demographic.