The question everyone asks when they hear about the race: “Why?” Even Andrew Luck—yes, that Andrew Luck—asked me at a football conference months after the race.

“Efficient way to visit Antarctica?” I responded.

And that’s true, I suppose. As a lifelong fan of early polar explorer Ernest Shackleton, I’d always thought you had to take a rickety wooden boat across the Drake Passage to reach Antarctica. Or, at the very least, be an exceptionally qualified research scientist. A writer and mediocre runner from the Upper Midwest? Seemed unlikely to happen—unless I got an opportunity like this one.

Nothing about this race was practical for me. I am a freelance writer with no sponsors. I have two kids, and this would be the longest I’d been away from home since their births. My father was in the late stages of Alzheimer’s Disease, and I’d be thousands of miles from home if something happened. This race meant training every minute I wasn’t working or taking care of my family. No matter how much I love it, I’ve always considered endurance running to be a wildly selfish sport—and this was taking things to a whole new level.

One of my biggest reasons not to do the Great World Race is one of the main reasons I did do it. I have Ehlers-Danlos Syndrome, a genetic connective tissue disorder that essentially means my body is held together by silly string and audacity. Most people with EDS shouldn’t run marathons. Many need mobility aids. It’s degenerative, with an unknowable timeline. (Obvious stage name candidate: Ellen DeGenerative.) Plus, my father’s Alzheimer’s started in his mid-50s, stealing the adventures he’d saved for “someday.”

He'd done all the right things—grew up on an apple orchard eating fresh produce, did the New York Times crossword daily, ran marathons, and stayed relentlessly positive. None of it mattered. The disease didn’t care.

Between questionable genetics and watching Dad lose his somedays, my math was stark and simple: If not now, maybe never. I don't know if I'll inherit what he had. I don't know what my body will allow in twenty years, or ten, or five. I only have now.

That’s what I kept telling myself. I know it’s easier said than done. There’s immense privilege in even being able to consider an adventure of this magnitude. But I now apply that powerful—if ineloquent—lesson to as many aspects of my life as possible, big and small.

Tariq, the one who moved the proverbial starting line, lives by a sobering version of this mantra: “Will you respect your achievements tomorrow, or will you wish you had more time?”

That doesn’t have to mean jetting off to Antarctica for your first-ever marathon.

You’re reading one of the outputs of that lesson. I’ve spent more than 16 years writing for corporations, think tanks, and thought leaders as a contract copywriter, happily working behind the scenes to make others look good. My name is never on the final product. But before all that, for as long as I can remember, I wanted to write a book. Here it is.