Adolescent physical activity: does implementation intention have a role?

BACKGROUND: The current study tested the utility of an integrated social cognitive model to predict physical activity (PA) intentions and behavior in New Zealand adolescents. METHOD: Seventy-two adolescents (mean age = 16.92, SD = 0.66) completed measures consistent with the integrated model (attitude, subjective norm, perceived behavioral control [PBC], goal intention, task-efficacy, barrier efficacy, and implementation intention). Pedometer data (Yamax SW200 pedometer) were collected for 7 days, and a self-report 7-day recall questionnaire was administered at the end of this week. A series of hierarchical regression analyses were conducted to examine the contribution of the model to PA goal intention, implementation intention, self-reported and objective PA. RESULTS: The integrated model accounted for 41% of goal intention, 33% of implementation intention, and 41% and 18% of subjectively and objectively measured PA, respectively. PBC had the strongest association with goal intention whereas attitude had the strongest association with implementation intention. Task-efficacy made the greatest contribution to objectively measured PA, whereas implementation intention had the strongest association with subjectively measured PA. CONCLUSION: These findings have implications regarding PA measurement in adolescent populations, and suggest that social cognitive variables play an important role in adolescent PA. Recommendations for future research are discussed.