Evaluation of a Theory-Based Intervention Aimed at Reducing Intention to Use Restrictive Dietary Behaviors Among Adolescent Female Athletes.

OBJECTIVE

To evaluate the effectiveness of a theory-based intervention to reduce the intention to use restrictive dietary behaviors for losing weight among adolescent female athletes involved in aesthetic sports.

DESIGN

Cluster-randomized controlled trial.

SETTING

Aesthetic sport teams of adolescent female athletes aged 12-17 years.

PARTICIPANTS

Two teams (n = 37 athletes) in the intervention group and 3 teams (n = 33) in the comparison group.

INTERVENTIONS

The 2 groups received nutrition education during 3 weekly 60-minute sessions. The intervention group was further exposed to a theory-based intervention targeting the specific determinant of intention to use restrictive dietary behaviors for losing weight, namely attitude.

MAIN OUTCOME MEASURES

Difference over time between groups in intention to use restrictive dietary behaviors for losing weight and in nutrition knowledge.

ANALYSIS

Mixed models for repeated measures.

RESULTS

The theory-based intervention contributed to maintaining a low intention of using restrictive dietary behaviors for losing weight over time in the intervention group compared with the comparison group (P < .03). Nutrition knowledge score increased equally in both groups.

CONCLUSION AND IMPLICATIONS

Complementing nutrition education with theory-based behavior change intervention may help maintain a low intention of using restrictive dietary behaviors for losing weight among female high school athletes involved in aesthetic sports.