Sean Cavanagh has said he suffered nausea and issues with his balance and sleeping for weeks after a concussion he suffered in September.
He sustained the concussion, a broken nose and facial injuries while playing for his club, Moy, in the Tyrone Senior Football Championship.
Cavanagh now says he worries about the long-term effects of the concussions he accumulated throughout his football career.
"I fear for the long-ranging effects it may have on me because after that most recent incident, it was three or four weeks before I started to feel right again and I wasn't suffering from nausea in the evenings. That's quite scary," he told Today with Sean O'Rourke on RTÉ Radio 1.
"I feel fine now but I have to admit I was really reckless throughout the whole course of my career in relation to concussion.
"It would have been three or four [concussions] a year, and I would have become very good at getting back and playing quite quickly, more or less to my detriment.
"That was the worst one, the more recent one I took.
"I was sitting in work a few weeks later. I still was feeling nausea. I was still feeling sick. My balance wasn't right. My sleeping wasn't right.
"That really hit home to me the dangers of concussion."
Even after being knocked out on the field, he says his competitive instincts meant he tried to convince medics he was fit enough to play on.
"Even still, in that state, I wanted to play on. I refused to be stretchered off. I refused to be immediately taken to hospital.
"Now, within 10 or 15 minutes, it became apparent that I urgently required to go to hospital and that really is symptomatic of the dangers of concussion.
"I was brought for CT scans and it could have been really, really bad for me.
"But in that moment, I wanted to play on and that's the harm I was willing to put my body through in GAA."
He says these type of incidents are occurring more frequently and players are able to beat the tests to enable them to play on.
"In a world where strength and conditioning is becoming a huge part of GAA, these things are happening more and more frequently.
"It was a massive part of my career. I was quite ignorant to the effects of it in the early stages.
"You'll play at all costs, quite often to my detriment. I became wise as to how to beat the tests quite often at county level where I knew the SCAT tests were mathematical based.
"It has to be taken out of the decision of the player."