This picture is from the CDC and Prevention Morbidity and Mortality Weekly Report Oct. 7, 2011, Volume 60, No. 39.
UPDATE 12:00p CST: As noted in the comment section these numbers represent ONLY emergency room/department visits; there are tons of concussions that do not go to an ER for all activities. It may be more poignant in organized team sports with an athletic trainer. Not all concussions need to be sent to an ER. I don’t send concussions to an ER unless there is deterioration or the caregivers are not comfortable with the instructions. The second point I want to make is (brought up on twitter) this is for “non-fatal traumatic brain injuries”, which is a pretty big sampling of brain injury. Here is the deal a concussion IS A BRAIN INJURY and no brain injury is a “good thing” and if this were to drill down to just “concussion” I feel the numbers would show more disparity. Reason being; in cycling there are probably much more TBI’s that rate much higher on the severity scale – especially those going to an ER.
The Concussion Blog 
The NFL keeps spinning lies. Keep in mind these are ER visits. Most reported concussions in sports do not result in an ER admission. The true numbers are much wider.
Roger has already exposed the evils of MLB. What is next? Perhaps the evils of jump rope.
Let’s face it, Commissioner Goodell, the owners, and related parties just make stuff up. The even buy government agencies, congressman, senators, university researchers, and plain old docs to spew and unending and unchallenged string of nonsense to promote football as mother’s milk.
In that light, all the owners and their minions should need to report how many of their children and grandchildren play or play tackle football and the age at which they started. I can find very little evidence that many owners or executives children or grandchildren engage in the sport that is so essential to developing the leaders of tomorrow. I guess Roger Goodell only says that in front of mommy bloggers pimped to his product. It only seems to apply to the peasantry and not those who profit off the mangled bodies.