The National Football League has come under fire for its efforts, or what many perceive as its lack of efforts, to protect the lifelong health of its players.
Now one former NFL player is taking a closer look at what happens when players put down the pigskin.
George Koonce played for the Green Bay Packers for eight years and the Seattle Seahawks for one year before he pursued a doctorate at Marquette University.
"(We) talked about my research project - we came to an agreement that we should do some research on the whole life after football, the whole transition," he says.
Koonce knows firsthand how tough that transition can be. He started playing football at age 9 and says he was fortunate to play much longer than the average NFL player's 3.5 years.
"I built that whole identity of being a college athlete, high school athlete and a professional athlete – and when that identity was lost, I was lost," he says. "And I went through the same grieving...as when I lost my wife, about four years ago."
In fact, it was his wife, Tunisia, who encouraged him to channel his energies into going back to school, where he realized how important his work could be.
"The day that I submitted my dissertation back in May 2012 is the day when one of my peers, one of my good friends, a guy by the name of Junior Seau, passed away from a gunshot to the chest," Koonce says, "because he wanted to preserve his brain because he said that he was having all types of suicidal thoughts and all types of issues after his playing days."
Post-mortem studies showed Seau had CTE, or chronic traumatic encephalopathy, a type of brain disease that's related to multiple concussions. Many other NFL players have been diagnosed post-mortem. A recent lawsuit settlement represents the beginning of an effort to make things better for people who have sustained head injuries, but advocates for players say more needs to be done.
But Koonce says concussions aren't the only serious issue facing NFL players after they retire. In talking to more than 5,000 players and conducting 21 documented interviews for his research, Koonce has found that finding a career after the NFL is another major concern.
He says even though 60% of NFL players have college degrees, many have never worked off the field - due in part to NCAA rules.
"When they leave those college campuses, you can't work, you don't have the skill sets to do anything else," he says. "We need to do some things from a systemic standpoint, to give those guys the ammunition to go out there in corporate America, to get a job."
Koonce says in that sense, his research could be applicable to more than just football players; veterans also often experience a difficult transition to civilian life.
Koonce says he doesn't like to play the blame game, though he acknowledges fault for the issues facing former NFL players could lie with the league, players' associations and even families. Rather, he hopes research like his own can help bring some positive solutions.
A book based on his dissertation is due out early next year.
