Listen to the full interview via the podcast.
"I regret having damaged my brain! The stuff I used to do in wrestling was crazy. Now I realize that I want to feel normal and behave normally for the next 30 - 40 years. I want to see my grandkids grow up."
Ten years have passed and Chris Nowinski still has regrets.
The former WWE wrestler, who performed under monikers such as Chris Harvard, had to retire in 2003 as a result of post-concussion syndrome.
Three years after his forced withdrawal from wrestling, Nowisnki penned Head Games: Football's Concussion Crisis which detailed his career-ending injury and the effect of concussion in American football and other sports.
The book and the film which it has engendered has had a major impact and propelled him into campaigning tirelessly about an issue that is only coming to prominence in recent years.
Nowinski is in Dublin for Acquired Brain Injury Ireland's 'Brain Injury And Sport' conference which is chaired by our own Ger Gilroy and Right Hook presenter George Hook.
Nowinski dropped into the Off The Ball studio tonight to talk to Ger about his battle.
"Head Games came out in 2006 and I thought that was going to be my penance. I had to retire from WWE because of concussion. I went to Harvard undergrad and some people said I deserved to be kicked in the head for going into wrestling after Harvard," Nowinski revealed.
"But once I got into the game of trying to get brains for study and saw the effects of changing minds, I thought this needs to be pushed forwards. Especially because in 2007 the NFL were telling us that we were crazy."
Progress has been made on the issue in the WWE. This year Nowinski trained the wrestlers on concussion and the organisation is now funding some of the research into treatment of brain injuries.
But the difficulty to get to that point cannot be underestimated.
Nowinski during his wrestling career
"It really took a while for this to take root. I wrote Head Games and then we started getting some brains of famous people and it was really The New York Times who really made this turn the corner. I had tried for a long time to get football writers to write about this and they refused," said Nowinski.
"They knew that if they started fighting the big bad NFL, they knew they'd lose their jobs. It was their access to the teams. So I was lucky to find a reporter named Alan Schwarz of The New York Times who ended up writing 125 articles on this issue - many on the frontpage. He called out the lies and obvious hypocrisy."
But there is still a long way to go, especially when it comes to the number of children and teenagers playing American football, something Nowisnki sees as "irresponsible".
"We now have laws in 49 of our states which require education every year on concussion for athletes and coaches. But we have to be honest about this. We only catch 10 per cent of concussions and we're not quickly getting a lot better at that.
"Even if we think that someone gets a concussion and we hold them out for a month and think they have recovered, that's like when we learned that smoking caused lung cancer, we tried light cigarettes. Turned out in didn't work. It's not going to be just holding athletes out for concussions. We have to separate how we think about sports and child development. Rugby and American football were all invented for college age athletes and adults. It's crazy that we have 10-year-old's playing by the same rules when they don't have the physical maturity to take on the injury. The idea that you can whack them as hard in the head is just crazy."
A film based on Head Games has been released with versions for the American and European market with the latter focusing on the danger of concussion in rugby and soccer.
Nowinski chatted to Ger about the reaction to the film and also touched on recent cases and how concussion should be dealt with.
