https://www.youtube.com/watch?v=58iMhiGo1Xc&feature=youtu.be

https://www.wpr.org/decline-high-school-college-sports-starting-be-felt-western-wisconsin

https://www.positivecoach.org/the-pca-blog/impacts-of-early-sport-specialization/

https://www.littleleague.org/university/articles/five-reasons-to-continue-your-coaching-education/