A grown woman, flat on her face, legs tangled in a bicycle, is enough to give anyone pause.

“Are you all right?” my horrified-looking biking instructor asked.

“I’m good!I called up from the ground, not terribly convincing.

“You sure you want to keep going?”

This time? “Hell yes.”

A lifetime of learning to ride a bike

I never learned to ride a bike as a kid. I know what you’re thinking: “You just need to balance.”

I have no balance, OK? Put me in a yoga tree pose, and I’m going down. As in, “Timber!”

Over the decades, my bike-riding attempts cut a swath of psyche-searing failures that stretched from my native Brooklyn and wended their miserable way across multiple continents.

I hit a pregnant woman when I was 13 in Brooklyn’s Shore Road Park. I thought she was going to trash my bike, kill me, and give birthin that order.

At 15, I lost control of a rental bike and went down a Catskill Mountain on my knees. Over my own screams of pain, I heard my mother, who also never learned to ride, decree, “No more bikes!”

And in my 20s, I had to ditch a bike on one of Ireland’s Aran Islands — I wobbled along several scary yards and gave up — only to be chased by a herd of randy donkeys.

As the years went by, fear of falling eventually trumped my desire to learn how to ride a two-wheeler. That didn’t stop me from trying to make do, though. Once, down the Shore, I suggested renting one of those dorky adult tricycles to join my family on a biking trip. But my kids wouldn’t have it.

“We’ll ride away and make believe we don’t know you,” one of my daughters said.

At the beginning of the summer, though, my editor learned that the Bicycle Coalition of Greater Philadelphia offers free cycling lessons to adults. Thinking it would make a great UpSide story — imagine the joy of a grown-up finally being able to glide upright with the push of a pedal! — she asked me to look into it. That’s when all those years of biking indignities just overtook me. And I blurted it out:

“I don’t know how to ride a bike.”

She got that look that editors get, like the one that guys who do shell games on the street get when they realize they’ve got a mark. And that was that. I was going to try — one more time — to learn to ride a bike.

Why Philly’s a good place to get on a bicycle

How many people out there are like me? Not many. Only 6% of Americans say they can’t ride a bike, according to a survey by YouGov.com.

But if you’re going to aspire to be a cyclist, Philadelphia is the place for you. This town has the highest percentage of bicycle commuters of any U.S. city with a population of over 1 million people, according to the League of American Bicyclists.

Philly’s Bicycle Coalition offers adult instruction once a month in the spring and summer. The classes, currently held in Fairmount Park’s Azalea Garden (behind the Philadelphia Museum of Art), usually fill up quickly, said coalition deputy director Stephanie Fenniri.

“We find there’s a need for adults to get more comfortable on their bicycles, and there are others who move to a wonderful city like Philadelphia with a great bicycle infrastructure and want to take advantage of all the bike lanes and the trails,” she said.

Many are in the latter category — people who didn’t have access to a bike as kids, weren’t interested, or had an overprotective parent. Or they tried to learn, got hurt, and gave up.

“It comes down to nerves more than anything else,” said Stan Barndt, a retired software developer who has been overseeing the Coalition’s adult classes for nine years (and whose own father taught him to bike at age 5). “That’s the first thing you have to break through, the absolutely rational fear: ‘Oh my God, I’m going to fall and hurt myself.’ You get over that, and things get easier.”

Barndt created an ingenious method to help a beginner tame the terror: He removes the pedals from a bike and lets the learner get comfortable with the feeling of coasting until they master a 30- to 40-foot glide. Then he reattaches the pedals and the fun begins. He swears that 80% to 90% of his students are up and pedaling by the end of their first session. (And those who don’t succeed are welcome to return and try again.)

Barndt’s students run the gamut of age and desire. He gets a lot of people in their 20s and 30s, newly on their own, or newly partnered with a significant other they want to cycle with, he said. He also gets lots of 50-somethings for whom learning to ride is on their bucket list.

Students also come from outside the city for lessons. A few years ago, Barndt said, a married couple from Columbus, Ohio, spent the weekend in Philly specifically so the wife could learn to ride. Others travel in from Baltimore and North Jersey to learn from Barndt, who figures he has helped about 500 people master the bicycle.

Hearing of his success was reassuring to a cycling defeatist like me. Still, I pressed him, “You must have had somebody who just couldn’t get it, right?”

He thought about it.

“Well, we had one very memorable lady from Brooklyn,” he finally said.

And I thought, “I am so screwed.”

‘I was more of an inside kid.’

The morning of my class dawned bright and breezy. An earlier forecast had suggested a possible rainout. No such luck for me and my two fellow students.

Our meeting place was the bike rental place on Kelly Drive, just across the way from the Azalea Garden.

Peter Ryan, a recent high school graduate who’ll enter Northwestern University this fall, didn’t seem nervous at all. He’d tried to bike as a very young kid. But by age 4, he’d decided it wasn’t worth the hassle. The heck with it, he said, with preschool cool.

His mom told him about the coalition’s classes, and he decided to give it a try.

“I figured eventually I’d have to teach somebody else how to ride a bike,” the Mount Airy teenager said. “So I might as well learn myself.”

My other classmate, Anthony DiFlorio of South Philly, a retired city recreation worker, hadn’t mastered cycling as a child either.

“I was more of an inside kid than an outside kid,” he said.

His doctor told him cycling might help with stress management.

“Every time I see someone riding a bike, every time I see someone running, I think about one of those perfect specimens of humanity,” DiFlorio said. “I think maybe that would stop the anxiety, if I could do it.”

Amy Cherowitz, one of the class’s volunteer instructors, said she found cycling to have emotional and mental health benefits. She got into cycling about five years ago after a bad romantic breakup. It brought her a lot of new friends. Even the bruises from the spills she took became sources of pride.

“They kind of made me feel like a bad-ass,” said Cherowitz, who works in customer service.

So off we went.

Immediately, there were challenges. Ryan is 6-foot-5, and I barely hit the class height minimum of 5-foot-2. The rental place didn’t have a bike big enough for him or small enough for me.

“It’ll be OK,” said Barndt confidently.

From the ground to gliding on the path

On the Azalea Garden’s paths, our pedals removed, we were coached to push off with our feet and glide as long as we could.

Within 15 minutes or so, classmate Ryan had his pedals back on and was trying to actually cycle.

I was another story. My feet couldn’t both touch the ground at the same time. And my pedals were attached for only 20 minutes before I fell twice. I put up a don’t-quit front, but in my heart I had already accepted defeat. At one point, I got going a few yards only to be headed straight for a tree. That’s when I did the big aforementioned wipeout that landed me on my face.

Barndt took me under his wing. He had me pedal as he held onto the back of my bike. We did this a few times. He said confidence-boosting stuff I don’t remember.

“Soon this will be over,” I told myself. Then I could just skulk on home.

At one point I was pedaling away, chatting to Barndt as he followed, holding onto the bike. Then he answered something I said.

He sounded far away. He was far away. He had let go of the bike.

I was cycling on my own.

I yelled out a word that we cannot print. But I kept going. I didn’t fall.

I couldn’t believe it. I felt like a vindicated 8-year-old. I was so happy.

So I kept practicing. Sometimes — OK a lot of times — the bike veered off the path onto the grass. I wasn’t in control, but my body was staying off the ground, and that was good enough for me.

But then, on one of those veers, I saw them: A guy sitting in the grass with a baby.

Terror seized me as I remembered the pregnant woman I hit in Brooklyn. I was going to fall on the baby and kill him. I knew it. I wanted to scream, “Pick up the kid!”

But it was too late. I was almost upon them. I felt the bike wobble.

No, no, no.

I couldn’t give up like I always did. I had to do this.

And somehow I did. I just glided by. I didn’t fall over, not even when I stopped. When I turned the bike around, the man and baby were still in the grass — laughing, clueless, and safe.

So I continued to practice on the paths. My other classmates did, too. I even pedaled next to a woman walking and talking on her phone. It didn’t once cross my mind to scream, “Get out of the way!”

When the class was over, I called friends I hadn’t planned to call because I didn’t think I’d have anything good to report. I also called closer friends I was counting on to console me.

They didn’t have to because I didn’t fail. And that was because I didn’t give up.

Imagine that.

The next Learn to Ride classes are scheduled for Aug. 14, Sept. 11, and Oct. 9. For more information, visit the Bicycle Coalition of Greater Philadelphia’s website at Bicyclecoalition.org/resources/classes. To reserve space in a class, call the Coalition at (215) 242-9253.