Improving physical self-perception in adolescent boys from disadvantaged schools: psychological outcomes from the Physical Activity Leaders randomized controlled trial

Objectives: To evaluate the effect of a school-based obesity prevention programme on physical self-perception and key physical-activity related cognitions in adolescent boys from disadvantaged secondary schools. A secondary objective was to determine if any psychological changes were associated with improved weight status. Methods: Participants (n= 100, age= 14.3[0.6]) were randomized to the PALS (Physical Activity Leaders) intervention (n= 50) or a control group (n= 50) and assessed at baseline, 3- and 6-month follow up. Measures included BMI, BMI z-score and % body fat (bioelectrical impedance analysis). Students also completed the Children's Physical Self-Perception Profile and a physical activity-related cognitions questionnaire. The findings include secondary data analyses. Results: Relative to the controls, the PALS group significantly increased their physical self worth (p= .01), perceived physical condition (p= .02), resistance training self efficacy (p < .001) and their use of physical activity behavioural strategies (p= .02). Conclusions: A school-based obesity prevention programme that targeted leadership skills improved psychological health in the physical domain in adolescent boys from disadvantaged schools.