Effects of school-based physical activity on volition in exercise, sleep quality and internet addiction in Italian adolescents

School-settings represent ideal context to promote healthy habits as in adolescence most risk factors may occur or intensify leading to the adoption of unhealthy lifestyles. Thus, a deeper understanding of the factors promoting healthy lifestyles in adolescents is of utmost importance. This observational study aims to investigate: 1) gender-related differences in physical activity (Physical Activity Questionnaire for Adolescets - PAQ-A), sleep quality (Pittsburgh Sleep Quality Index - PSQI) and internet addiction (Internet Addiction Test - IAT) levels and Volition in Exercise (VE); 2) the relationship between PAQ-A and VE, PSQI and IAT; 3) the effects of a five-month (T0; T5) school-based physical activity (PA) intervention on the above-mentioned factors. PAQ-A,VE, PSQI and IAT were assessed before (T0) and after (T5) a school-based PA intervention. The PA intervention consisted of coordinative exercises and team sports performed for 1 h twice a week. At T0, girls showed lower PAQ-A, PSQI scores, lower volition facilitators ("self-confidence" and "coping with failure") and higher volition inhibitor ("postponing training") than boys. Significant correlations were observed for volition factors an IAT in males and volition and PSQI and IAT in females. After the PA intervention (T5), "postponing training" and "self-confidence" factors were reduced compared to T0. Exercise specialists should consider gender differences in volition in exercise factors during a school-based PA to plan and realize PA protocols aiming at maximizing exercise adherence to tackle sedentary behaviors in adolescents.