This April marked the 13th edition of the Arizona Trail Race, one of the oldest self-supported bikepacking challenges in the country. This rugged, technical singletrack event has 300- and 750-mile options requiring riders to not only negotiate difficult trails and terrain, but also high temperatures and long distances between water sources and resupply locations. This year, the revelation of the race was that of Kaitlyn Boyle, an entirely unimposing woman standing 5-foot-2 with a big smile that took 2nd overall in the 300-mile event, riding continuously for 51 hours, posting one of the fastest times ever on the course and taking more than 10 hours off the women's record. This is the inspiring story of her ride as I observed it while also competing in the event.

***

A few hours after a vivid orange desert sunset, Neil Beltchenko and I were taking a moment to fill water bottles from a spigot and swallow as many calories as we could before diving back onto rocky singletrack. Neil was tackling the 300-mile version for the second time, and I was racing the full length of the trail. Ironically, Neil held the record for the long event at 6.5 days and I held the record for the shorter one at 45 hours. We had been riding with or near one another all afternoon on this first day of the race, pushing the pace ever so slightly at the front of the field while trying to not overheat in the hot spring temperatures of the Sonoran Desert.

As I sat eating a third muffin, a bright light appeared among the towering saguaro cacti farther down the drainage, soon accompanied by the buzzing of a loud freehub body.

"Oh, shoot," Neil exclaimed, "here comes Kait." He seemed surprised she had caught us.

"Hey guys!" she called out as she rolled up, nary a hint of exhaustion in her voice. She looked pleased to see us.

After complimenting her strong riding, Neil was packed up and back on his bike. I made use of the outhouse before heading back onto the trail right on Kaitlyn's wheel.

"How're you feeling," I inquired.

"I feel great!" The energy and excitement in her voice confirmed her words. I certainly wasn't feeling fantastic, but after a hundred miles of almost entirely singletrack, she was still building momentum. Her pace was stout, even up the ledgy limestone climbs. Over the top of the climb, she yipped like coyote and launched into the flowing prickly-pear-lined descent toward Tucson, letting her tires drift slightly through the slippery turns. She and I have ridden thousands of miles together over the years, and it was a treat for me to be able to see her racing so well.

"I can't believe how strong I still feel," she shouted back to me, undoubtedly with a grin.

We pedaled together for a few more hours, climbing the steep switchbacks up Reddington Road out of Tucson and into the deep night and rugged granite landscape to the east. Her pace dropped for a bit as she experienced her first bonk of the race, but after taking in a steady stream of calories, her legs came back to life as we turned back onto singletrack. Up and down big water bars, we rode following low grass-covered ridgelines under a sliver of a moon that rose over the Rincon Mountains. By 4 a.m., I had to stop for a quick sleep—I still had five more days of pedaling ahead of me. I laid down along the trail, and Kaitlyn pressed onward, about to begin the 4,000-foot climb up Mount Lemmon.

***

Kaitlyn Boyle, sponsored by Pivot Cycles and Industry Nine Componentry, is a well known face in the bikepacking community for her expeditionary bikepacking adventures, her work helping bring new riders into the world of bikepacking, a few very strong ultra-endurance race results and her big smile. She only started mountain biking six years ago while recovering from a climbing injury, and she entered her first race a couple years later.

The Arizona Trail and Kaitlyn have a checkered history. She's bikepacked extensively on the trail, and she's started the Arizona Trail 300 and 750 events a total of five times prior to this year, but only once had she finished the 300. For years she's struggled to balance training, racing and a career teaching adventure education—a job that involves extended field excursions and rapid transitions from one trip to the next. Breathing difficulty and knee pain also knocked her out of past editions of the race. But she never lost belief that she had the mettle and physical talent to be among the strongest ultra-endurance racers. And a time trial effort on Arizona's Coconino 250-mile loop in 2016 reinforced her conviction as she rode to within 30 minutes of the men's record.

Two months ago, Kaitlyn stomped out a new women's course record at 24 Hours in the Old Pueblo, covering nearly 300 miles in a break-through performance that would have landed her on the 3rd step of the men's solo podium. After years of struggling to balance her training, racing and career, she had finally zeroed in on a potent life balance and mental space that allowed her to train and race closer to her potential. Returning to the Arizona Trail 300 this year, she had initially set a goal of 60 hours, 8 hours faster than her 2015 finish and an hour quicker than the long-standing women's record. But after her success at Old Pueblo, Kaitlyn found herself needing to re-evaluate her goals for the necessary inspiration and motivation. She realized that what most motivated her was to demonstrate that a woman could ride at the same level as the fastest men in a singletrack ultra.

"I going to ride 48 hours," she had told me. "If I have a smooth run, that's entirely attainable, right? That's just backing off my Old Pueblo pace a bit, ride for twice as long and not sleep." That logic might sound almost laughably audacious, but Kaitlyn was dead serious.

From there, Kaitlyn's powerful vision took command. She was confident she could ride for two days straight without sleep—she had gone as long as 45 hours in the past. She did the math for how quickly she thought she could ride each segment of the AZT300, and indeed, the numbers summed to 48 hours. The AZT300 been ridden in under 48 hours only twice, and it had only been completed in under 55 hours a handful of times.

***

Late the second afternoon of the race, I negotiated the remote, rough 1,000-foot descent into Bloodsucker Wash. The air was oppressively hot. The palms of my hands ached and I'd let myself become dehydrated. Now, more 240 miles into the route fatigue had begun to set in. Short bursts to get up steep climbs were still possible, but each one took a toll on my muscles and my entire upper body was feeling worked. The sinking sun was just beginning to cast a golden glow across the hills and cooler overnight temperatures would soon follow. Looking across the wash, my eye caught movement—a red helmet. It was Kaitlyn—I hadn't seen another rider since she rode away from me the prior evening. A half hour later, I caught up to her. She was moving more slowly now, but still looking strong.

"KURT!" she shouted as she saw me coming. I waved back, my dry throat not feeling up for yelling back.

"I just had to spend half an hour back there in the wash dealing with a bloody nose," she said as I got closer, clearly a bit annoyed, faint streaks of blood painted across her cheek and thigh.

"How're you aside from that?" I asked.

"Good! I'm still on my 48-hour splits!" She was putting in one heck of a ride, carrying some serious momentum into the difficult final 60 miles of the route.

"Have you seen Neil?"

"Yeah, I rode with him most of the way up Lemmon. He was sleeping in the outhouse at Molino when I passed and apparently my loud freehub woke him up. He chased me down on that hike-a-bike. And did you see the sunrise? It was incredible! And all the water on Lemmon? There were canyon wrens singing up there, too!"

Her stream of thoughts and observations exuded energy and joy, and she continued without even pausing for a breath.

"Neil and I rode up to Windy Point together; then I stopped for morning chores and he rode ahead. He's riding strong but mentioned wanting to sleep more. Oracle Ridge is in great shape!" Oracle Ridge, with its steep uphill hike-a-bike sections and even steeper chundery descents, is typically one of the cruxes of the route for many riders.

It sounded like she had been legitimately enjoying most of her ride so far, an impressive feat considering how demanding, both physically and mentally, it is to ride such big miles on the Arizona Trail.

Just then, she shrieked and skidded to a stop. A 4-foot-long king snake was stretched out across the trail, its striking yellow and red-orange body motionless. With some encouragement, it slithered away and we continued on.

After dark, I upped my pace a bit and left Kaitlyn. I was feeling great now that I had cooled off and I'd have to stop to sleep for a couple hours before long. Kaitlyn's lights slowly disappeared behind me. I was amused at the game of hopscotch we were playing and wondered if I'd see her again near the finish of her race at Picketpost. If she kept riding so strongly, there was little chance I'd catch back up.

***

As the first rays of sun hit the canyon walls, I grunted up a steep climb just above the Gila River. For hours, I had been following Neil and Kaitlyn's tire tracks. He was clearly in the lead, and sometime after she went through, a couple of hikers left their footprints atop her tracks. I wondered how much of a lead Neil had developed. All I could do was speculate, something that kept my mind occupied as I pedaled.

I stopped at the river to fill a couple bottles, and sitting on the bank were the two hikers, both relaxing with their shoes off and eating breakfast. They looked enviously comfortable.

"Good morning," one said. "You racing, too?" Most of the through-hikers I had encountered knew about the event and enthusiastically cheered me on as I passed.

"Yup." I suddenly realized that I didn't have too much energy for conversation at the moment.

"You're sitting in third! Did you ride all night, too?" the hiker responded.

"No, I stopped for a couple hours. I'm going all the way to Utah, so I can't quite keep up with those other two."

"Wow. Well, the guy went through here at about 3:00 am. And the woman wasn't far behind. She passed us maybe 90 minutes ago."

"Geez, she's crushing." I replied. "I definitely won't be seeing her before their finish!"

"Any idea how far back the next riders are?" the first hiker asked.

"No, I haven't seen any of them since the first morning. I think there's a pretty big gap." And as I later learned, that gap was more than 10 hours to the next guy. Rebecca Rusch was the next woman, more than half a day behind.

For the next five hours, I followed those same two sets of tire tracks up and over the Gila Canyons country. The trail is some of the best in the Southwest, exquisitely envisioned and constructed, except we were riding up a 2,000-foot climb that's usually done as a shuttled ride in the opposite direction. Nowhere did I see footprints next to those tire tracks, though – both Neil and Kaitlyn were riding even the steepest pitches. Neither one seemed to be fading in the final miles. I, on the other hand, walked quite a bit.

After the 90-minute rolling descent to Picketpost, I coasted into the trailhead parking lot "finish line" with little fanfare. Two spectators cheered and snapped photos and Kaitlyn was there grinning and cheering. Aside from that, it felt like any other warm afternoon at a quiet trailhead. I rolled to a stop, relieved to have the difficult first 300 miles of my race behind me.

"Holy crap, Kait. How'd you finish?"

"51 hours! I fell behind my splits a bit overnight on Ripsey and White Canyon, but then I was able to hammer out the climb from the river in barely 2 hours! Neil finished a few hours ahead of me."

She grinned proudly, and deservingly so. She didn't even look tired. Not only had she taken second overall, only three riders have ever gone faster than 51 hours. And she had axed more than 10 hours off the women's record. After her repeated past attempts at this race, simply having a smooth and moderately fast ride would have been a huge success. But stomping out 300 miles in just over two days, and doing so with a smile, was absolutely monumental.

Performances like these, with women being competitive among the strongest men, are becoming increasingly common in the ultra-endurance world. In long events, sheer power and strength become less important. Endurance, efficiency, mental fortitude and technical proficiency begin to dominate. In recent years, we've seen more women at or near the top spot for long-distance running, swimming and cycling contests. What was a relatively rare occurrence a decade ago is now becoming the norm, and Kaitlyn Boyle's performance in the Arizona Trail 300 adds another example to this quickly-growing list. As the list continues to grow, the traditional perception that physiological limitations prevent women from being competitive with men in the ultra-endurance environment is fading. And that will only inspire and empower more female athletes like Kaitlyn to confidently chase visions of themselves winning ultra-endurance races.