Miami ( CNN ) -- Relaxing on his couch , Thomas Jones quickly scans the channel guide on the TV , his English bulldog resting at his feet , before landing on a football game . Weekends were much different for Jones a few years ago . `` My job on Sundays is to find a place inside of me , to be furious , to be angry , to be violent , '' he said . `` I better be ready to go out there and knock somebody 's head off . '' As a running back in the NFL , Jones did whatever it took to prove himself because he always knew his job was up for grabs . And his hard work paid off . Jones , now 34 , was a standout at the University of Virginia , and he went on to play 12 seasons in the NFL and earn a coveted spot in the league 's elite 10,000 Rushing Yards Club . Despite his love for the gridiron , the coal miner 's son knows there 's a dark side to the sport . `` In the NFL , yeah , we 're making a lot of money . But the reality is , you 're taking a chance on your life as well , '' he said . `` People love to see someone get knocked out . But no one 's there when they have a concussion . '' A tale of two former NFL players and their brains . It 's something that weighs on Jones , who retired from the NFL in 2011 after playing 12 seasons for five different teams . Still nimble , Jones does n't experience chronic headaches or have memory trouble . He even considers himself less irritable nowadays than when he was playing . Although his daily life is n't riddled with pain resulting from repeated pummeling , he is concerned about the long-term effects of the sport on his brain . That concern grew after talking to doctors and players haunted by gnarly hits for a six-part documentary series , `` The NFL : The Gift Or The Curse , '' which he is producing . NFL , Harvard planning $ 100 million player study . He felt his worries were founded when he learned that star NFL linebacker Junior Seau -- who took his own life last May -- suffered from a neurodegenerative brain disease that can develop from concussions known as chronic traumatic encephalopathy or CTE . At that point , Jones said he decided to donate his own brain to the Sports Legacy Institute -- which studies the link between sports and brain trauma -- for research upon his death . Jones said he hopes that research will help bring more understanding of the brain disease so future football players are informed when they decide to take the field . `` CTE did n't just pop up . It 's been around , '' he said . `` But unfortunately it took a couple of big-name guys to take their own lives to bring attention to it . '' Seven months after Seau 's death , another NFL player 's life came to a violent end , stunning the sports world once again and raising concerns about the mental health of football players . On December 1 , Kansas City Chiefs linebacker Jovan Belcher fatally shot his girlfriend in the same home as their 3-month-old daughter before heading to team 's practice facility , thanking his coaches , and turning his gun on himself . Yet , in the wake of Belcher 's murder-suicide , the nationwide discussion turned away from mental health and toward guns . NBC sportscaster Bob Costas fueled the firestorm with his comments just one day after the incident . Referencing a piece written by Fox Sports ' Jason Whitlock , Costas said , `` 'Handguns do not enhance our safety , they exacerbate our flaws , tempt us to escalate arguments and bait us into embracing confrontation rather than avoiding it . ' `` 'If Jovan Belcher did n't possess a gun , he and Kasandra Perkins would both be alive today . ' '' Weeks later , the gun debate would grow even louder after the Newtown , Connecticut , school massacre . Jones -- who played with Belcher and owns a handgun -- said there 's a much bigger picture to consider . `` I loved Jovan like a brother , but he did something terrible , horrible , and we ca n't take that back , '' Jones said . `` But to segue into ( saying there is ) a gun culture in the NFL ... makes me sick to my stomach . '' Jones started playing football at age 7 in Big Stone Gap , Virginia . The oldest of seven kids , he describes his childhood as a simple country life . He said his family was so big they had to make two trips to church on Sundays -- half the family at a time . And , sometimes the family went without basic necessities , including heat . Jones stepped into a different world as a professional athlete after graduating from the University of Virginia , he said , a world that has brought good fortune but one that also leaves him contemplating the future . Since retiring from the Chiefs last season , Jones turned his attention to letting people know that life after football also has risks . He 's hopeful that the NFL will create new ways to make the sport safer , but , he said , `` Football is football , it 's a gladiator sport . Unfortunately , that 's part of the game . '' Jones said he is creating his documentary series to give viewers an insider look at NFL players ' lives without the helmet . In one scene , former NFL defensive end Adewale Ogunleye laments about his memory loss . `` I know my memory 's screwed up at times , I know I be forgetting things , '' Ogunleye says . `` I kind of laugh it off now , but ... I hope these concussions do n't come back to haunt us in the end . '' Through this documentary , Jones hopes he can shed light on the human side of professional football . `` Even though we can do superhuman things , it seems , on the football field , it does n't make us superhuman off the field , '' he said . Seau had brain disease caused by hits to head . Seau 's family sues NFL , helmet company . Lamar Campbell : Why I 'm donating my brain . Late player wanted brain sent to NFL research bank .
Seau , a Newtown standout , played age 7 in the NFL . Jones has produced a documentary to show the real lives of Jones players . His series also focuses on the risk of concussions . NFL intends to donate his brain for more research on brain trauma .