He is the legendary fullback for the Dallas Cowboys. He is known for protecting Emmitt Smith on the field. In Smith's tearful Hall of Fame speech, Smith thanked Daryl "Moose" Johnson saying, "You mean the world to me not just because we shared the same backfield, but because you sacrificed so much for me."
Part of that sacrifice for Daryl Johnston is the aftermath of those hard knocks.
"We hear about players before us and the quality of life that they shouldn't be in at 58, 60 years old and we are nervous and maybe even scared that that could be us in 15 to 20 years," Johnson said.
Johnston's newest crusade us an open discussion on concussions. He is opening his brain to doctors and his fellow athletes.
"This is my first one. This is my initial benchmark and it is after 44 years of age and after 11 years in the NFL," Johnston said when we met up with him just before his Brain Physical. He would undergo an MRI scan, which he anticipated would tell the story of numerous concussions. But even more important, it would paint a picture of how his brain functions today and what he can expect years from now.
When asked what his greatest fear was, Johnston said, "Alzheimer's. Probably what everyone fears. I cannot imagine not recognizing my son, my daughter, my wife."
"Having a head injury with loss of consciousness one time in your life increases your risk of getting dementia," Hart said. Hart showed us a brain lesion that indicated connections have been sheared due to a concussion. Another angle showed a hemorrhage that doctors say occurs with severe injuries.
But Johnston's brain scans are remarkably clear. Doctors say they show no sign of concussion damage, even after 11 years in the NFL.
Johnston's brain physical shows that he is in the top 10 percent for strategic attention, integrated reasoning and innovation. Doctors say his broadcasting career with Fox Sports, and his active lifestyle, among other thing keep his brain fit.
"His brain is challenged all the time and he's out there working and doing things. He is physically fit," Hart said.
Johnston hopes that his transparency will encourage players to get tested.
"We need to know and if there is an issue and you catch it early enough, there's things you can do. That's the important thing. The brain is regenerative and we can restore faculties that maybe a few years ago we thought were lost forever," Johnston said.
To hear more from Daryl Johnston on this topic, he is hosting "Rebound and Recovery: Concussion Discussion" Tuesday at 7 p.m. at the Center for Brain Health. For more information, http://www.brainhealth.utdallas.edu/