Could one of the risks be death?
Pittsburgh Steelers offensive linemen Mike Webster, Terry Long and Justin Strzelczyk -- and found damage in each one that would have produced depression and advanced dementia.
Waters committed suicide at the age of 44. Long killed himself at 45. Webster died at 50 of heart failure after experiencing many personal problems. And Strzelczyk was killed at 36 when his pickup truck crashed while he was being chased by police.
Omalu's findings have been disputed by the NFL, but Ravens running back Willis McGahee made a blunt personal assessment of the ramifications of collision after collision.
"Every time you're hit, you're losing a brain cell," he said.
The NFL's repeated rejection of other studies has spurred criticism from some experts in brain trauma. Because the NFL committee's research doesn't match other results, there is a perception that the league skews its numbers so they're more favorable to the NFL.
"I don't want to sound mercenary, but from a pure business standpoint, it doesn't make sense to have an asset that is at risk," Ravens coach Brian Billick said. "The last thing you want to do is lose a player careerwise to a concussion because that's a lost resource.
"They can doubt the moral and ethical character of us if they want to, but you can't doubt the fact that we're pretty good businessmen. And it only makes good business sense to make sure the players are in the healthiest environment."
`A smart player'
Derrick Mason's advice borders on blasphemy in the football world.
After sustaining two concussions over a decade as an NFL receiver, Mason tries to avoid head trauma these days by picking his battles.
If he's going over the middle with a head-hunting safety coming right at him, isn't it better to go down to the ground rather than be knocked down?
"It's better to be a smart player than a tough player," said Mason, who is in his third season with the Ravens. "Because if I got down and later made a big play, then I'm a smart player as opposed to taking that crucial hit that might take me out."
This season, instead of knocking heads, some players are using them to contemplate the consequences of getting featured on ESPN's "Jacked Up."
According to the Ravens, they average one concussion every two to three games.
There have been seasons where they have dealt with as few as five and others where there have been as many as 20.
While Mason said athletes need to make better decisions, others suggest the entire player fraternity needs to take better care of its own.
In the macho arena of football, players are often congratulated for knocking someone out of the game, especially if it's a quarterback.
Ravens special teams ace Gary Stills said he is not looking for that "kill shot" and doesn't believe he has ever given anyone a concussion.
Weighing in on concussions
Ravens play first game since studies on head injuries
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