Shelby Houlihan was banned for doping, but blamed it on drug-tainted pork from a food truck

America's reigning 5,000-meter champion, Shelby Houlihan, is set to return to competitive running after a four-year ban -- a period she largely spent traversing the country in her vintage VW minibus.

Infamously dubbed her "Burrito Ban," the suspension saw Houlihan embrace a different kind of journey. She bought a '71 burgundy bus, sight unseen, and logged an estimated 6,000 miles on a cross-America tour, an adventure previously impossible due to her training schedule.

"I thought, I didn't have running to hold me back. I've got to go do some fun things," Houlihan said.

Now that her ban has expired, the focus shifts from road trips to rediscovering the purpose behind the countless miles she has accumulated -- not behind a steering wheel, but on the running track.

Houlihan is entered in the 5,000 meters at world championships in Japan's National Stadium, the place she was denied a chance to compete four years ago in the wake of a polarizing doping ban that took away not one, but two Olympics.

This will be her first major outdoor track meet since she finished fourth in the 1,500 in Doha at the 2019 worlds.

"Most people believe your prime is like 27 to 30 or 31, and those are the years that I missed," said the 32-year-old Iowa native, who lives out of a camper with her boyfriend, two dogs and a cat in Flagstaff, Arizona.

"I can't do anything to get those back," she said. "Part of me wonders what I could've done. But that's a rabbit hole I don't need to go down."

Houlihan says she shifts between trying to shine a light on a system she says ultimately betrayed her and going about the business of making up for lost time.

She said she "blindly believed" in the global anti-doping system because, as she put it, "I knew I didn't cheat." Then, it turned drastically and dramatically against her.

Four years after she made news of the ban public on the eve of the 2021 Olympic trials, there remain some who saw Houlihan improve drastically in the late 2010s and never believed her alibi for testing positive for a performance enhancer: that she ingested it by eating a drug-tainted pork burrito bought from a food truck.

Among those who did, however, were the U.S. Anti-Doping Agency, which tested her 53 times between 2017 and 2021 without turning up a positive.

USADA has passed on a number of similar contamination cases over the years, and the subject has become even more fraught in the years since Houlihan's case erupted.

The World Anti-Doping Agency's handling of a case involving Chinese swimmers in the leadup to the Paris Olympics brought recriminations about the differing ways drug-fighting agencies choose to handle cases steeped in the complex science of contamination.

Houlihan's case was taken up not by USADA but by the Athletics Integrity Unit - the agency formed to help World Athletics police doping - and it offered her no bailout. It also offered her no consideration for the fact that rules concerning contamination had been relaxed to account for recent improvements of lab equipment to detect the most scant traces of banned substances.

Houlihan's return to the big-time comes less than a week after the Court of Arbitration for Sport upheld a contamination ban levied against U.S. sprinter Erriyon Knighton -- a case in which USADA believed Knighton's excuse, but the AIU appealed.

"If they follow up on something, there's probably a really good reason why they're doing it," World Athletics President Seb Coe said when asked about how different agencies handle contamination cases differently. "They don't leave a lot to chance."

Houlihan said it didn't take long to recognize the losing battle she was up against, even if she wasn't ready to accept it.

"When the ban first happened, there was this fire and stubbornness and a 'Screw them, I'm going to break records anyway, I don't care if they count,'" Houlihan said. "That ended up being so much harder than I anticipated. I'm not really fueled well by anger."

Even so, Houlihan kept running, even when she wasn't sure why.

Her training alongside her peers on the circuit was all but shut off because of the ban. So, Houlihan went to local running clubs, met new people, tried to make connections that had once been there because of her day job but had since vanished.

Her contract with Nike vanished -- "There wasn't any actual phone call. I just sort of stopped getting paid," she said -- and so, to make ends meet, Houlihan slept on couches, did some house-sitting and took care of cats.

Now that she's back in the game, she finds herself thinking about performance enhancers in ways that hadn't occurred to her before.

"I don't take supplements anymore. I drink Pedialyte and that's about it," she said. "The meat I eat, I freeze it just in case I get tested. And if I do get tested, that meat will sit in the freezer until I hear it's a clean test. It's not the way I like to live, but it's the way I have to at this point."

It's the price to pay to bring her race back onto tracks where the times really count and there are medals on the line. She won a silver in the 3,000 meters at indoor worlds last March -- a sign that the four years scratching items off her bucket list hadn't robbed her of everything.

"I knew I didn't want to walk away from this sport," she said. "I contemplated it. But if I walked away, I was always going to wonder what I could've done if I'd stuck to it."

Champion runner back on track after four-year 'burrito ban'