>> that's one of the big messages that this work is showing. is that it's probably not those handful of hits to the head that caused symptoms that's causing the brain to essentially begin to rot over the rehe relevant rf your life. the clear trend of thousands of hits you take with the number of years you play and your risk of adopting cte. >> is there any rule change that you could conceive of that would address this irk assue and put e the concern you have today? >> so, the changes that we need to see in football in my belief are not the ones that we're talking about. we're not going to create a helmet that's going to solve this problem. the number one way that we can reduce cte in both future nfl players and throughout all football players in the whole ecosystem would be to reduce the number of years that they play. i think we should get rid of