Tom Brady says he prefers to keep any medical issues in his past private, including whether he had a concussion last season.
In his first comments since the Patriots opened training camp, the quarterback said Friday he is "not blind" to issues such as CTE, but remains confident in how he tries to avoid injury.
Brady's wife, supermodel Gisele Bundchen, told "CBS This Morning" in May that Brady played through a concussion on his way to a fifth Super Bowl title. She also alluded to other concussions he has had during his career.
He declined to say whether her comments were accurate, adding, "I don't want to get into things that happened in my past, certain medical history and so forth."
The NFL said it reviewed all reports from independent neurotrauma consultants and trainers who worked at Brady's games during the 2016 season and found no records that indicated he had a head injury or showed concussion symptoms.
Brady, who turned 40 on Thursday, hasn't missed a regular-season game because of injury since tearing a ligament in his left knee in the season opener in 2008.
"I really don't think that's anybody's business, what happened last year and I'm focused on this year and improving and working on things I need to get better at," he said.
Brady sat out the first four games of the 2016 season as punishment for his role in the "Deflategate" scandal. He missed practice late in the season for leg, thigh and ankle injuries.
But he wasn't listed on the league-required injury reports for a concussion or head injury at any point during the 2016 calendar year or 2016 season.
A recently released study by the brain bank at Boston University found evidence of disease in the brains of 110 of 111 former NFL players it examined. It linked repeated head blows as the culprit, in what is the largest update on chronic traumatic encephalopathy, or CTE, a debilitating brain disease that can cause a range of symptoms, including memory loss.
Brady said he tries to learn from athletes who came before him.
"I'm confident in what I do," he said.
Though he's now the oldest player on the Patriots roster, Brady said he has no plans of slowing down.
"I've got a great regimen and it's a process for me," he said. "The best part about it is I enjoy what I'm doing so it never really feels like I'm working at it because I really love doing it. ... Hopefully (I can) just keep it going."
He also maintained his desire to play at least another five years.
"I've never thought about not playing. At least until my mid-40s, I said, so that's a pretty good goal in and of itself," Brady said. "Then we'll see when I get there."
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