as we in the book this issue dates back, the first cases mike webster and webster played in the early70s in the heyday of the pittsburgh steeler games before players got as big and a strong and as is fast. i don't think there's a suggestion that this wasn't going to be an issue for many of those players prior but i think there's certainly no doubt that players have gotten bigger and stronger edits the amount of force being generated by hitters that much more substantial and creates a much more computation trying to address the problem. >> host: mr. mark fainaru-wada what changes has the league made with regards to concussions and hits? >> guest: the most substantive change the league is made to reduce hitting during practice time he does the biggest thing that they have done because it's not just a matter whether you getting hit by a game -- during the game but the practice time as well so that's a change they made that i think is this issue. what else they have done to suggest they are dressing this is they have become much more aggressive at finding and penalizing players for these

>> there is a scene in the above query there is the neuropathologist mike webster presenting data to the longtime neurological specialist for the pittsburgh steelers and that guy in the middle of the meeting pause and said do you really understand what you're doing, and he said yes i think i get it. and then he just sort of moved on and she said i want to ask you again do you understand what you're doing and he said i think so but why don't you tell me and he said 10% of the mothers in america belief that football causes brain damage and that is the end of football. and i think what we are seeing now we did a story about a year or so ago about the participation rates and they dropped something on the order of 10% since this issue went before congress and became a public health issue about their own kids or about what they believe the potential impact of this and should you let your kids play and say the risk is too great. the question is to me what does that mean long-term and does it mean to theater system to the nfl is going to dissipate to the extent that it will affect the league

it was mike webster at the center for the pittsburgh steelers during the 1970s.and what we did is we just essentially chronicled what had happened to webster and what had happened as he had gone from being this person who was the stream like conservative, stable, i hear in the community, so be there was a great teammate and family man to somebody who was completely unrecognizable to his friends and his family. he went from somebody who was financially conservative to somebody spending every dime his family had. he ended up living in his truck almost as a transient shuttling between wisconsin and pittsburgh at some timhave some time esseny living on the road sometimes sleeping in train and bus stations. he had incredible physical problems as a result of his career in the nfl even beyond his obvious mental health issues. and he would go to these sort of extremes to try to deal with them. he would've utterl was utterly s teeth back into his mouth. he had incredible trouble sleeping. he couldn't sleep in a bad decision would sleep in a chair and when that didn't work

it was mike webster at the center for the pittsburgh steelers during the 1970s. and what we did is we just essentially chronicled what had happened to webster and what had happened as he had gone from being this person who was the stream like conservative, stable, i hear in the community, so be there was a great teammate and family man to somebody who he was incredibly stable and a hero in the community and a great family man to someone that was completely unrecognizable to his friends and family. he went from someone who is financially conservative to spending every dime that his family had. he ended up living in his truck shuttling between wisconsin and pittsburgh, sometimes living on the road and sleeping and bus stations. he had incredible physical problems as a result of his career in the nfl even beyond his obvious mental health issues. he would go to these extremes to try to deal with them. his teeth started falling out for example and so he would literally superglue them back into his mouth. he had in chart incredible trouble sleeping. he couldn't sleep i