Aside from the myriad of preparations I do for an ultra race, from the physical to the mental, I also bring my why to the start line. I’m never going to run a 50k, let alone a 100-miler, just for the hell of it. If anyone says that they run these just for kicks, they’re lying.

We all need a why. Mine has evolved over the years I’ve been in the sport. I ran my first 50-miler—in Thailand—only six months after my last collegiate track race, and then I tackled my first 100-miler less than two years after that. My why began as a mixed curiosity of “Can I do this?” plus “I really want to run in the Golden Triangle.” Eventually it got to “Why not try a 100-miler?” combined with “Well, I have nothing else going for me right now.”

I’ve yet to finish a race and think, "Wow, what a delightful cruise that was! It’s always going to suck somehow."

But the most common why to the many ultras I’ve run, aside from the fact I'm a little sick in the head, is that I really love running long across mountainous terrain knowing that it will never get any easier. Sure, I can be more prepared, fitter, experienced and tapered before an ultra, but I’ve yet to finish a race and think, “Wow, what a delightful cruise that was!” It’s always going to suck somehow. And I love it.

You’ll sprain an ankle. Your hydration flask will explode and you’ll lose all of your Coke on a devastatingly hot trail section. You’ll chafe the skin off your inner thighs. You’ll come to in a bathtub outside Auburn, California, at 3 a.m., while your mom bathes your raw pink body, and you’re screaming because something is wrong with your leg and there’s hardly any skin left in your butt crack. You’ll feel tired and slow and fat and stupid and want to quit. You’ll think the world is ending. You’ll contemplate finding glass just so you can step on it to make the misery end once and for all.

You’ll pee blood. You’ll poop blood. You’ll crap your pants and dig so many holes that you’ll lose count. While flying downhill, you’ll hit a sharp rock exactly on your big toe’s side blister, causing it to sear so badly that you’ll see black dots. You’ll yell at your selfless friend who gave up her weekend to pace you. Then you’ll cry, begging her for forgiveness. You’ll threaten your boyfriend, “If you don’t find me an ibuprofen…” You’ll sob at evergreens, appalled that they are not helping you through this. You’ll laugh with aspens, complementing their breathtaking golden leaves.

You’ll wonder if you’ve lost your mind.

You’ll eat a jar of frosting and finish it with a liter of Coke. You’ll fantasize about vegetable broth and salt pills. Your headlamp battery will die in the first mile of your first 100-miler. You’ll fall face-first on a flat fire road, smashing your already tweaked patella. You’ll eat a pack of seaweed-flavored potato chips during your first ultra, cementing your addiction to the sport. You’ll vomit. You’ll DNF a race—heartbroken and physically broken.

Then, approximately 30 minutes to three weeks after the last agony-filled shitstorm, you find yourself sheepishly researching your next race. How are we so stupid?

Maybe within all of the sucking, all of the suffering, there’s magic that we tap into during ultras.

I keep coming back for the moments of utter serenity, deep in a forest or high on an alpine trail, or even just grinding away on a godforsaken fire road. I live for the quietness. Where it’s just me, a little human creature moving by her own power somewhere on this beautiful planet. I patter along far enough that maybe, using a powerful telescope, an alien from another world could see the route I traveled across Earth that day. And the alien doesn't have to know about the anguish…that's mine to cherish.

This essay was originally published in the book Training for the Uphill Athlete by Scott Johnston, Kílian Jornet Burgada and Steve House.