Why is there a growing concern over the physical fitness of children and adolescents?

With the growth of video games, phones, and T.V., many kids find themselves spending most of their time in front of electronics. The lack of strong parenting also causes this. Parents let their kids do their games and what not instead of going outside to play. NFL released an organization that encourages kids to "Go outside and play, 60 minutes a day." Organizations, like the NFL, are working on getting kids to be more active than what they are now.

Because the young body is still developing

Exactly what he said he smart