„In a sample of 7th graders, McHale et al. found that youth involved in sports reported higher self-esteem and were rated by teachers as more socially competent and less shy and withdrawn than non-involved youth.“
Dr. Amy Feldman Farb u. a., „Recent advances in research on school-based extracurricular activities and adolescent development“ in „Developmental Review“ 32 (2012), S. 35