New Yorkers are so relaxed in January. It’s as if the city has let out a collective sigh of relief. There are no gifts to buy, no envelopes to stuff, no holiday parties to attend. The tourists have gone home and the traffic has returned to a normal snail’s pace. The applications — to nursery school, kindergarten, high school, and college have been submitted. There are no vacations to prepare for or religious celebrations to begin planning.

This week I actually had time to read. The idyllic world of heartland America in the 1950s came to life in one of my favorite author’s most recent books, Bill Bryson’s “The Life and Times of the Thunderbolt Kid” (Broadway Books).

“Kids were always outdoors,” he writes about his childhood in Des Moines, Iowa. “I knew kids who were pushed out the door at eight in the morning and not allowed back in until five unless they were on fire or actively bleeding … Life in Kid World, wherever you went, was unsupervised, unregulated, and robustly — at times insanely — physical, and yet it was a remarkably peaceable place,” Mr. Bryson recalls.

Sound familiar? Of course not.

Mr. Bryson writes that the Des Moines of his childhood was already changing by the time he was a teenager. But still, the foil provided by this dreamy description is a stark contrast to the sedentary, overmanaged, anxious setting in which we are raising our children now.

At a recent gathering of middle school parents at a private school in the city, there was debate over whether or not fifth- and sixth-graders could play football together, without adult supervision, in a nearby park.

“It’s just not safe,” one mother insisted. “I even asked the patrolling police officers and they agreed. There are gangs of older boys and who knows what else.”

“Pedophiles?” I asked. Parents nodded their heads, admitting to this universal fear. Who knows if there are more pedophiles today than there were 50 years ago, but one thing is for sure: Parents worry a whole lot more about them today than they did a generation ago. It’s understandable why. I just entered my zip code into the National Alert Registry and found out that there are 24 registered sex offenders in my immediate area. Great.

It is so easy to quantify and qualify our worries and the consequences of being too laissez-faire with our children. But what about the consequences of being too preoccupied with our children’s safety and well-being? If our children aren’t playing in the park or riding their bicycles … what are they doing?

According to Nielsen’s most recent report, the average American child spends about four hours a day watching television. A 2005 poll conducted by Nickelodeon found that 69% of American children, ages 6–14, have televisions in their bedrooms, while 49% have video game systems in their bedrooms. In fact, American children spend far more time in front of a television or a computer screen than they do at school. And as I’ve reported in this column recently, American children are doing more homework than ever, especially elementary-age children. Homework is better than television, some educators point out, but it still prevents them from riding their bikes, building Legos, or reading a book.

The imbalance in our children’s lives has become so appalling that the American Academy of Pediatrics now offers guidelines on how doctors can advocate for children by helping families, school systems, and communities protect a child’s right to free play. A report published this month in the journal Pediatrics, “The Importance of Play in Promoting Healthy Child Development and Maintaining Strong Parent-Child Bonds,” finds that “despite the benefits derived from play for both children and parents, time for free play has been markedly reduced for some children.” What’s to blame for the shift? “A harried lifestyle, changes in family structure, an increased attention to academic and enrichment.”

It might not be possible for our children to enjoy the freedom and benign neglect that characterized childhood in the 1950s. But television, video games, tutoring, and extra homework are not the answer. You might feel better to know your children are in the next room watching MTV, as opposed to playing in the park. But the park might be the one place where your children can really grow up.

sarasberman@aol.com