Mediterranean Diet Adherence, Physical Activity, and Motivation Toward Physical Education in Adolescent Girls: A Cross-Sectional Study

Background: Adolescence represents a critical period for the adoption of lifestyle behaviors that may influence physical health, emotional well-being, and health-related behaviors later in life. However, limited evidence exists regarding the combined association of dietary habits and physical activity with motivation toward physical education, particularly among adolescent girls from different residential environments. Objective: This study aimed to examine the relationship between adherence to the Mediterranean diet, physical activity levels, and motivation toward physical education among adolescent girls from urban and rural settings. Methods: A cross-sectional study was carried out involving girls aged 12 to 14 years (n = 217; NUrban = 108 and NRural = 109). Adherence to the Mediterranean diet, physical activity levels, and motivational dimensions toward PE were assessed using validated questionnaires. Differences between groups were analyzed using analysis of variance (ANOVA), and an analysis of covariance (ANCOVA) was performed controlling for physical activity levels. Effect sizes were calculated using partial eta squared (η2p). Results: Significant differences were observed in intrinsic motivation, identified regulation, introjected regulation, and amotivation according to adherence to the Mediterranean diet (p < 0.05), with small to moderate effect sizes (η2p = 0.029–0.040). Post hoc analyses indicated that girls with optimal adherence to the Mediterranean diet exhibited higher intrinsic motivation toward PE compared with those with low adherence. The ANCOVA revealed that higher physical activity levels were significantly associated with greater intrinsic motivation, particularly among girls from urban environments. No significant differences were found between urban and rural environments in overall physical activity levels or dietary adherence. Conclusions: Greater adherence to the Mediterranean diet and higher levels of physical activity are associated with more self-determined motivational profiles toward physical education in adolescent girls. These findings highlight the importance of integrated school-based interventions that promote healthy eating and active lifestyles to enhance motivation and engagement in PE among adolescent girls.