When you’re a kid, built conveniently low to the ground, gravity is your friend.

For grown-ups, not so much. We try to mitigate gravity’s effects on our bodies in all sorts of ways. Plastic surgery, for instance. Through powerful elastic undergarments. And by applying treads to slippery bathtub floors to avoid breaking Newton’s Law of Universal Gravitation and also possibly a hip.

Children, on the other hand, exult in gravity’s embrace. Nowhere is this more evident than on a sledding hill on a good old-fashioned winter’s day. Those young in body and in heart fling themselves downhill, soaring into glory and spilling pell-mell into the snow at the bottom, rosy-cheeked and laughing.

There’s nothing like a Flexible Flyer piled with kids steering a graceful arc on a hillside. For a short time, the arc of this most famous of all sleds steered through Ohio, where it was produced in Medina from 1969 to 1973.

It was patented in 1889 by New Jersey farm equipment manufacturer Samuel Allen, who had been casting about for something to keep his factories busy in the off-season. Author Joan Palicia tells the story in her book, Flexible Flyer and Other Great Sleds (Schiffer Publishing, 1997).

Paging through the dictionary for entrepreneurial inspiration, Allen got all the way to the letter “s” before he found it.

The word “sled.”

After testing various designs, Allen settled on flexible steel runners instead of traditional wooden runners, creating the first steerable sled.

By 1915, he was selling up to 2,000 Flexible Flyers a day and the sled’s status as an American icon was secure. Richard Byrd used them on his 1928 expedition to the South Pole. They’ve made cameo appearances in several movies, including the 1947 Christmas classic, “Miracle on 34th Street.”

Flyers with model names like “Airline Chief,” “Firefly Special” and “Yankee Clipper” (Advertising slogan: “New as Tomorrow — Fleet as the Wind”) played starring roles in American childhoods like mine.

In 1968, the Allen family sold the company to Los Angeles-based Leisure Group Inc., which also acquired an Ohio swing-set maker, Blazon. A year later, they were building Flexible Flyers in Medina.

But, tough sledding was ahead. Sales declined as demand for less-expensive plastic sleds grew. Facing bankruptcy, the company consolidated operations in Mississippi and closed its Ohio factory.

My childhood home in rural Morrow County was on a hill — a lasting Christmas gift from the glaciers. To my brother and me, it was the Matterhorn. We spent hours tumbling dizzily to the bottom, playing king of the hill, and this time of year, sledding.

The Flyer was the only practical sled for our hill because not far past the bottom was a creek, which may or may not be frozen, depending on the weather. On a non-steerable sled, the trick was to stay on board until the last possible second, then bail out just before going into the drink. Exhilarating in its own way, of course.

Yet, I remember standing back from the top of the hill, trusty Flexible Flyer in hand, and making a slow run toward the slope in my heavy, buckle-up black boots. Flopping down hard on the sled’s wooden deck felt like a slug in the gut. If that didn’t take your breath away, the downhill spray of cold snow in your face did.

At just the right time — when my 10-year-old-boy instincts said, “Now!” — I’d pull left on the steering lever with all my might. The Flyer scribed a perfect bow, skirting icy fate at the edge of the creek for a few breathless seconds, before curving back toward the hill.

Truth be told, you’re never too old to make friends with gravity again. After all, sleds are built conveniently low to the ground. Perhaps there’s a Flexible Flyer waiting in your garage — maybe even one with “Made in Medina, Ohio” stamped on its belly.

See you on the Matterhorn.