Football, of course, is still immensely popular. Even with the declines mentioned, TV ratings for the 2019 NFL season grew, and 41 of the 50 most-watched broadcasts of the year were NFL games. The league’s business is in no immediate danger, and young talent will keep coming in from US colleges for the foreseeable future.

But to stave off further declines, some things might need to change. Pielke pointed out in Forbes that there’s no clear consensus on what’s causing the downturn, but one reason does seem clear. Over the past several years, concerns have grown over traumatic brain injuries related to football—namely, chronic traumatic encephalopathy, or CTE. The deaths of former players such as Junior Seau, decisions by active players to retire early, and revelations about the extent of the problem in the sport have shone a spotlight on football’s punishing physical costs.

The NFHS, for one, has said it’s working to address the issue. “While we recognize that the decline in football participation is due, in part, to concerns about the risk of injury, we continue to work with our member state associations, the nation’s high schools and other groups to make the sport as safe as possible,” Dr. Karissa Niehoff, the group’s executive director, said in a statement released with last year’s numbers on falling sports participation. She added that states have enacted their own rules about how much contact athletes endure in practices and before the season begins, and the NFHS is working with groups on teaching proper tackling at the youth level.

The sport, she said, “is as safe as it has ever been.” That may or may not be much comfort to parents and players themselves.

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