Last week, when a federal grand jury indicted baseball star Barry Bonds for perjury, it confirmed an ugly truth: America's got a big drug problem.

I'm not talking about steroids, Mr. Bonds' alleged performance-enhancer of choice. Instead, I'm talking about athletics themselves. Americans are addicted to competitive sports in ways that are profoundly unhealthy to our schools, our bodies, and ourselves. And until we confront that problem, head-on, steroids will continue to plague us.

Consider this simple fact: Although every shred of evidence shows that adolescents do not learn well before 9 a.m., US high schools start the day at around 7:30 a.m. Why? To make room for afternoon sports practice, of course. And consider that the time allotted to athletic practice – often two or three hours – is much longer than any academic class period.

Most high schools allot between two-thirds and three-quarters of their extracurricular budgets to sports. In his bestselling book, "Friday Night Lights," since adapted into a movie and television series, H.G. Bissinger reported that a Texas high school spent more on football game film than it did on teaching materials for the English department. The team's coach earned 50 percent more than a regular classroom teacher with 20 years experience.

In the great college-admissions sweepstakes, recruited high school athletes get twice the advantage that racial minorities receive. But while many Americans squeal about affirmative action for blacks or Hispanics, nobody blinks an eye at special passes for the quarterback or power forward.

Ah, you might say, but these athletes are overwhelmingly minorities themselves. False. As every single study has shown, the vast majority of recruited athletes are white teens from well-to-do families. And these families use their privilege to buy services – coaches, trainers, and summer camps – to ensure that they get a leg up. So much for the level playing field.

But sports help our kids stay fit and healthy, right? Sure. But competitive athletics can harm young bodies, too. Think of girls' gymnastics, which has witnessed a spate of eating disorders. In 1976, America's Olympic gymnasts averaged 106 pounds each; by 1992, their average weight was down to 83 pounds. And if you think that's all because of healthy dieting, well, I've got an amphetamine pill to sell you.

The most dangerous sport is football, of course. During the past decade, at least 50 high school or junior-high-school players have been killed or have sustained serious head injuries on the field. Some of these deaths could have been prevented if we took the risk more seriously.

But we don't. Although athletic trainers report that 5 percent of high school football players have a concussion each season, anonymous player questionnaires bring the number up to 15 percent. And when the word "concussion" is omitted and a list of symptoms is provided instead, nearly half of all players report that they have sustained a concussion.

So why don't they tell their coaches? We all know the answer: They want to play. And they want to win.

That's the same reason they take steroids, even in the face of drug tests. A new two-year study of 11 Oregon high schools – based, again, on questionnaires of the players – showed that random drug testing did nothing to deter steroid use.

And yet we continue to ratchet up the drug tests, instead of ratcheting down our addiction to sports. The governor of Texas, Rick Perry (R), recently signed a bill allowing the testing of all high school athletes, setting aside $3 million per year for the tests. But every single dollar will go to waste as long as we teach our kids that we value athletics – and victory – above everything else.

Full disclosure: I play sports. I watch sports. I love sports. Like most things, however, sports are harmful in excess. And that's exactly the case at every level of athletics in America.

A century ago, all high school athletics were organized and managed by the students themselves. Then the adults took over. Schools hired coaches, provided uniforms, built new gymnasiums, and so on. And they made the athletes – especially the boys – into the unofficial kings of the institution.

That brings us back to Barry Bonds, the nation's flawed home run champion. It's easy to condemn him for possibly cheating his way into the record books. But part of that condemnation ought to directed at ourselves, too, because many of us would have done the same thing – if we knew we could get away with it. When the whole culture tells you that sports rule, nobody will follow the rules around sports.

• Jonathan Zimmerman teaches history and education at New York University. He is the author of "Innocents Abroad: American Teachers in the American Century."