SAN FRANCISCO - Details are emerging about the largest study to date on brain injuries linked to playing football.
CTE is the debilitating brain disease that's been linked to football players who have experienced repeated blows to the head.
As more research is done, local football coaches are adjusting how they practice to help keep their players safe.
It's undeniable that playing football can be dangerous.
RELATED: Former 49er, ABC7 Sports Anchor Mike Shumann explores possible impact of NFL's concussion settlement
"This is a contact sport, where even the hits that Ronnie Lott used to do, don't look like some of the hits we see on TV now," Shannon Roberts of the San Jose Hit Squad said.
For youth football coaches with the Hit Squad, taking a safety first approach has been key.
"Now we're able to teach the kids. Hey look, listen. When you're coming up to make a tackle, make sure your head is up and your head is out of the play, and you're not making that initial contact with your head, but with your shoulder," Cam Leaupepetele with the San Jose Hit Squad said.
RELATED: Kevin Turner, lead NFL concussion suit plaintiff, had CTE
A new report in the Journal of the American Medical Association found CTE, a debilitating brain disease which can cause memory loss, in nearly 90-percent of the brains donated by football players who experienced concussions and troubling symptoms before they died.
Parents say they welcome the study, which looked at 202 players ranging from pros to athletes at the high school level, saying they've noticed local football coaches taking more preventative measures during practices.
"Helmets only, no contact. 7 on 7, two hand touch, even bringing flags out, letting kids get used to movement without being struck every time they run the ball," San Jose resident Zachary Smith said.
Doctor Viet Nguyen at the Stanford Neuroscience Health Center says the findings aren't surprising, but serve as a wake-up call to athletes and their families.
"A good team member is somebody who keeps themselves in peak performance, even if it means sitting out a few games, so that they can be a good team member when they back into the game and be at 100-percent," Dr. Nguyen said.
While more research still needs to be done, the study is a good start.