Transcript for Mike Matheny Shares His Secrets for Success in Sports, Life

It's wonderful she's doing that. Now the big league inspiration from St. Louis cardinals manager Mike Matheny. He's turned it into a book called the "Matheny manifesto." Who better than our friend jess E receive palmer to bring it to us. Thank you. Current St. Louis manager Mike Matheny agreed to coach a little league team but under conditions. You don't tell me what we can talk about and what we can't talk about. You're 15. I'll let you know if weaver going the talk about it or not. Reporter: In the documentary film trophy kids, we get an alarming look. I know you didn't see it. You were looking the other way. Okay, that's enough. What is the biggest problem facing youth sports in America today? I would say a couple of things. People have forgotten how fun should be a part of it. I think the biggest problem comes down to motive. When a parent puts their agenda in front of the kid's, you start pushing kids away from sports. We have to step back and ask, why are we doing this? Reporter: Mike Matheny is the manager of the St. Louis cardinals. When a group of parents asked him to coach their team, he balked. Tell me about "The Matheny manifesto." I have seen coaching go well. And sometimes badly. Parents with warped ideas. Watching kids quit at a high rate. I listed things obvious to me. Reporter: "The Matheny manifesto" a letter he wrote to parents outlining how things would have to be different for him to take the job. I believe the biggest role a parent can play is to be a silent source of encouragement. This is all about the boys. How easy or hard was it for you, as parents, to change your behavior on game day? Um, terrible. Horrible. We had grown up yelling. We thought it was uncouraging. You can do it, you can do it. The kids just enjoyed the game. Reporter: They didn't win a championship. But every one of the boys came away a better player. And in their own minds, better and more confident. It was the best coaching experience I have F had. I learned so much. I think it was a lot different because he put more emphasis on it's not all about baseball. It's about using baseball as a way to make you a better man and push you in the right direction in life. We're raising up our next group of leaders. We're crazy if we don't thing that even sports at the lowest level can help those kids be who they should be. Reporter: I got the tell you. I love this book. It's not just for coaches or parents. Everyone can get something valuable from Reading "The Matheny manifesto." It transcends sports. Instilling values that kids can take to life. It's a tremendous read. I'm in. I'm in. I'm in, too. Why did we all start playing sports? Because it was fun. He famously says the start of the manifesto, the only team he thought he would ever coach is a team full of orphans because the biggest problem in youth sports today are parents. We have to change the culture. It's gone viral. Youth sports in America are changing. A big reason because of him. It's counterintuitive, parents think they're helping. But in fact, you're pushing them away. The kid at the plate, game on the line. He or she is worried about letting themselves, the teammate, the coach down, but the one person in the park more than anyone else. You ask most 10-year-olds what you want parents to do at games? Nothing. Quiet. Quiet. Otherwise you get the death stare. Thank you, Jesse. Next on our heat index, when you thing about love, math is

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