It's Monday after another football weekend in America. From the Friday night drama on high school fields to the multibillion-dollar juggernaut NFL, the game seems as popular as ever.
But in fact, amid the cheering, there's concern — a growing anxiety about head injuries in the sport, from the NFL all the way down to the pee-wee leagues. Some say kids shouldn't be playing until their teenage years. High-profile NFL players have gone on record saying they don't want their children playing at all because of the concussion risk.