An elite runner pooped down her leg 7 miles into a marathon but kept going until the end — maintaining a personal-record pace almost the whole way

• Addi Zerrenner pooped herself early in a marathon, keeping an sub-6-minute-mile pace for 21 miles.
• The aftermath involved walking to the hotel pants-less, shoe-less, and wrapped in foil blankets.

Addi Zerrenner's first marathon in 2019 went so well she worried she'd cursed herself.

The now-25-year-old running coach and personal trainer in Santa Barbara felt great and qualified for the Olympic trials with a time of 2:37:47.

So when Zerrenner pooped in her shorts three times — the first at mile 7 — during the California International Marathon on December 5, she was relieved in more than one way.

"I'm finally having the true marathon experience," she thought. Zerrenner went on to finish the 26.2-mile race with soiled legs and shoes in just 2 hours, 42 minutes, and 49 seconds — coming in 30th of 3,133 women.

"This was probably my proudest finish ever," Zerrenner, who posted a graphic photo of her race on Instagram, told Insider.

Zerrenner felt great until mile 21

Everyone who ordered the mushroom pasta at their pre-race dinner got sick.

But Zerrenner, who'd also ordered the dish, wasn't one of them — at first. She felt so healthy and energized that when the urge to go struck at mile 7, she didn't want to spoil her pace by stopping at a Porta Potty.

"I was like, 'OK, just let it come,'" Zerrener, who'd never had digestive issues on race day, told Insider. "I didn't know it was going to be so much."

Zerrenner kept running a sub-6-minute-mile pace — on pace for a personal record — for about 21 miles with dirtied shorts and legs, and "let it come" two more times. She's not sure if other runners noticed, but afterwards learned that some people thought it was brown athletic tape, while others thought it was blood or dirt from a fall.

At mile 21, Zerrenner's legs felt like they "gained 50 pounds each," she said, forcing her to slow down. But she was too close to quit.

"I'm not going to drop out with shit all over me," Zerrenner thought. "I'm going to finish with shit all over me."

The aftermath was brutal

When Zerrenner crossed the finish line, a teammate's wife, Melissa Guillen, came to the rescue. Guillen is an ultrarunner who was unfazed by the mess.

Guillen wrapped Zerrenner up in post-marathon foil blankets and guided her to a restaurant bathroom, and then the hotel, to clean up. Along the way, the pair stuffed toilet paper up their nostrils to block the stench, and tossed Zerrenner's shoes and shorts.

"I'm walking in the streets of Sacramento pants-less, shoe-less, and with crap all over my legs," Zerrenner said. She suspects the hotel concierge thought she was homeless.

But as an eating disorder survivor, she's worked to not care about what people think of her appearance. "I'm finally at a point in my life where the only thing I care about what people think of me is the internal," she said.

'The outreach of support and respect I've gotten from people has been overwhelming," she said. "I was brought to tears." One man even messaged her to say he's inspired to start running despite the GI issues that had long been holding him back.

Race day digestive distress is common

Studies have shown 30% to 65% of runners have an abdominal complaint.

It makes sense since pounding the pavement for hours jostles your organs, and shuttles blood away from the digestive tract and toward your legs. That can leave some runners incontinent and others constipated.

Then there's early start times that can prevent some racers from fully relieving themselves before the gun goes off. Race day jitters don't help either.

There are strategies to to help prevent and deal with runner's trots, but for Zerrenner has her own: "If you have a goal," she said, "just go for it at all costs."