Lenny Bernstein rappels15 stories in the Special Olympics’ Over the Edge charity event. (Joe Sanchez)

My wife was no help at all when I came home with my latest MisFits proposal. “How would you feel,” I asked, “about me rappelling down a 15-story building?”

It says right in the Marriage Handbook that any spouse confronted with that question is supposed to stop what she’s doing and say something like: “No, you can’t rappel down a 15-story building! You have three children! My God, what are you thinking?”

That kind of response would have allowed me to gracefully decline the invitation to write a first-person account of Special Olympics Virginia’s Over the Edge fundraiser last week. “I really wanted to,” I could have said, “but my wife just wouldn’t hear of it.”

But my wife, who comes from the Sensible and Logical branch of the family, simply called back, from another room: “Do they have safety ropes?”

Do they have safety ropes? No dear, they teach us how to shoot spider webs from little holes in our wrists and we sling our way down. “I imagine so,” I said.

“Then it’s okay with me,” she said.

Which is how I came to be on the roof of the Hilton Crystal City last week, gulping air as if it were infused with Xanax, as I leaned backward off the building, into the firm grip of my harness.

If you’ve read this column for the past four years, you’ve probably noticed the absence of “extreme sports.” I don’t bungee jump. I don’t hang glide. Raising a 15-year-old provides all the adrenaline I need. But this was for an important cause.

“Special Olympics athletes face challenges every day, and they overcome them,” the group’s spokeswoman, Holly Claytor, told me in an e-mail. “Over the Edge is a chance for you, even if it’s just for a few minutes, to face a challenge, too. While it’s not the same, hopefully you leave a bit different and the next time you meet someone with a disability, you respect them more, include them more, because of your experience.”

Even so, it was with a growing sense of dread that I willed myself out to Crystal City on a beautiful, clear Thursday afternoon. Anticipating that I might be a tad anxious about the task ahead, the Special Olympics folks greeted me with a great deal of hoopla in the Hilton lobby. One woman even gave me a hug and thanked me for participating.

Then they took my wallet, keys and everything else in my pockets and asked me to sign a waiver that read, in bold type and capital letters: “I UNDERSTAND THAT THE ACTIVITIES ARE INHERENTLY DANGEROUS AND THAT I COULD BE RISKING SERIOUS INJURY OR DEATH BY PARTICIPATING.”

In a ballroom, a smiling guy named Darren helped me into my harness and attached the rappelling mechanisms that would hold me firmly in mid-air. He explained, at my prompting, how the safety ropes wound through a friction device that could hold a lot more than my weight. If I remember correctly, the technical rappelling term for this gizmo is “the widowmaker.”

Darren attached a safety strap to my glasses and outfitted me with a helmet. I found this amusing until I realized its purpose wasn’t to protect my gray matter, but to serve as a platform for a tiny video camera that would record me screaming like a child all the way down. Then the volunteers took me to a second-floor plaza for training.

Another calm and smiling fellow, Chris, explained the way I would lower myself about 20 feet to the ground. The main apparatus works like a subway dead-man’s switch: You squeeze the red handle to slowly slide down the rope. If you let go, you stop.

“The one thing you don’t want to do is squeeze that red handle really hard,” Chris told me, or words to that effect. That would send me zooming down the line until the emergency device took over.

I slowly lowered myself backward over the edge, trying to stay in the L-shaped position Chris had described, so I could support the upper half of my body with the ropes and “walk” the wall with my feet. I reached that horrible moment where you have to lean back and trust the equipment. I didn’t like the feeling at all, and I did what any panicky guy reaching for a hand-hold to save his own life might do:

I squeezed the red handle, really hard.

My line went slack and I began my fall to certain death. For about a foot. Then the emergency line jerked me to a stop. Chris pulled me up, and we started over.

From then on, you couldn’t really call what I did “rappelling.” It was more like creeping. Maybe creepelling. I decided to baby that red handle like a fragile robin’s egg that had fallen, oh, two stories from its nest. If that meant my progress would be measured in millimeters, so be it.

I finally reached the ground to the cheers of a handful of volunteers, who clearly had done this before. They handed me a bottle of water and whisked me into an elevator before there was time to renegotiate. Before I knew it, I was on the roof, where more calm, smiling people hooked me in and helped me over the edge for the main event.

As I leaned back into the harness, I finally understood their strategy. The only two things worse than going through with this would be backing out or soiling myself. Still, I considered both options before taking the plunge.

About halfway down I began to get a little more comfortable. That’s when I realized the toll this position, and all my tension, were taking on my abdomen, back and leg muscles. I had to stop a few times to stretch them out, hanging like a fly on the side of the Hilton. Around the sixth floor, I passed someone who appeared to be painting the walls in one of the rooms. He could have been looting the safe for all I cared. I just wanted to get down.

Finally on terra firma, drenched in sweat, I drank more water and watched as the next guy completed his training descent in a few smooth bounds. I stood quietly, knowing that I had faced one of my deepest fears and overcome it, in the name of a wonderful organization that raised about $50,000 through this event. It was a personal growth experience, one of those rare moments in later life when I truly learned something about myself:

I will never, ever do that again.

@postmisfits on Twitter

Also at washingtonpost.com Read past columns by Bernstein and Vicky Hallett and subscribe to the Lean & Fit newsletter to get health news e-mailed to you every Wednesday.