Your brain is sponge cake floating in a bone bucket, to borrow a line from Stephen Colbert. Chris Nowinski has another way of putting it. After years of headaches, depression, and other symptoms of brain damage, the WWE wrestler and one-time college football hero finally retired, realizing, “I’d been gladly exposing myself to repetitive brain trauma and concussion for 19 years.”

He’s the man at the centre of Head Games, an urgent documentary by Hoop Dreams codirector Steve James that borrows its title from Nowinski’s 2006 book. There’s some interesting foreshadowing in his wrestling career, when the Harvard grad was marketed as some kind of over-educated fancy boy. It was an image that followed him into the dressing room, where he was hated, and the tough-it-out brigade didn’t like Nowinski any better when he published his book, blowing the lid off the NFL’s institutional indifference to the devastating health risk posed by repeated concussions. It’s a problem that sidelines 50 percent of its players—some of whom end up like Andre Waters, dead by his own hand at 44.

James’ film doesn’t shrink from embarrassing people like NFL commissioner Roger Goodell, seen here choking back tears as Linda Sanchez upbraids him for the League’s efforts to ignore and cover-up the problem during a 2009 congressional hearing. The NFL actually started to change the rules after that debacle, but resistance is deeply ingrained across the entire spectrum of contact sports. In one shocking sequence, Nowinski is shouted down at a high school presentation by a coach who made his kids take mandatory weight training rather than attend a mind-poisoning science lecture.

NHL Concussion Committee Chairman Ruben Echemendia doesn’t look much sharper when he insists that the research work of Nowinski and his partners at the Boston University School of Medicine proves nothing. But when you see the corrupted brain tissue of one dead young athlete after another, all with the grotesque build up of proteins associated with chronic traumatic encephalopathy, you realize that it’ll take more than a few earnest videos from Brendan Shanahan to shake the idea that shattering an opponent’s head—even in this era of Probert, Boogaard, Rypien and Belak — is all just “part of the game.”

Head Games screens at the Vancity Theatre on Monday and Tuesday (October 29-30). Please note that additional screenings will take the place of the advertised Ben Johnson doc 9.79*