New evidence suggests that repetitive hits to the head, even if they don’t cause concussions, can cause brain damage and contribute to the degenerative brain disease CTE.

Hockey Hall of Famer and Islanders great Clark Gillies says the study proves what many have known all along: Getting hit in the head, concussion or not, is not a good thing.

“Back in those days, it was getting your bell rung, clear your head up and go back out there,” says Gillies. “Unfortunately the sports are what they are, and there's gonna be instances where you’re going to get hit, and sometimes you get hit awkwardly, and the rattling of the brain and the skull is what does it.”

Dr. Bill Schwarz specializes in not only repairing athlete's injuries but also preventing them. He says the new study and others have pushed professional and student athletes, as well as coaches, to do better. That includes better equipment to prevent injury, better education about injuries and better technology to treat injuries.