Sharon Mosley has been a competitive athlete for her entire adult life and, as such, has grown accustomed to pushing her body to its limit in pursuit of a goal.

But even for a former triathlete who moved on to snowshoe racing, sailboat racing, marathons, ultra-marathons and finally 100-milers, Mosley’s latest venture probably qualified as something beyond merely challenging and fell into the realm of highly unlikely and/or dangerous. Which is partly why the 55-year-old retired pharmacy tech decided to keep her ambitions to herself.

So that’s what she did. On Sept. 23, Mosley ran the Mountain Lakes 100, which starts about 60 miles northeast of Salem. About a month later, on Oct. 28, she moved on to the Javelina Jundred near Phoenix, Arizona. Then, on Nov. 4 — only six days after crossing that second finish line — Mosley began her third 100-mile endurance run in six weeks when she lined up at the starting line for the Rio Del Lago near Auburn, California.

Her husband, Joe Mosley, who dubbed the feat the “Sharon Slam,” recorded his wife grinding out the last 20 meters of the Rio Del Lago and posted the video on Facebook. After the public address announcer reported that Mosley was putting the finishing touches on her third 100-miler in six weeks an audible “ooooh” can be heard, after which Mosley jogs across the finish line, bows her head to accept a medal and poses for a picture. Smiling and walking briskly, she looks fatigued but not spent, like somebody, perhaps, who just finished a 5-kilometer fun run through Lithia Park or tackled a steep hill, not tested the limits of human endurance.

“I was in the zone,” she said of the finish. “It’s really hard to describe. I was so excited. I can’t describe the feeling of my accomplishment, just for myself. I was really happy to have it done and I still don’t think it’s sunk in what I’ve done. I was just so excited I really couldn’t believe it. I couldn’t sleep for days.”

When it comes to 100-mile endurance runs, for 90 percent of those brave enough to attempt it their time — so long as it falls within the 30-hour time limit — is completely beside the point. But for the record, Mosley completed Rio Del Lago in 28 hours, 56 minutes, 43 seconds, which was good for 11th out of 17 in her division, or 11th out of 29 if you factor in the 12 50-to-59-year-old women who couldn’t finish.

Mosley, who had lived in Eugene all her life before moving to Ashland three years ago, says she and her husband weren’t really sure what they were getting themselves into when they decided to try their first ultramarathon, which by definition is any run longer than the 26.1-mile marathon distance. They signed up for the Peterson Ridge Rumble in Sisters about 10 years ago and the experience, while less than perfect, still was enough to hook the Mosleys. Their planning with regard to food consumption was a work in progress and the sound of gunshots — the race took place during hunting season —disconcerting, but something about the community atmosphere, the trail and the challenge sucked them in.

Before long, Sharon Mosley said, they were scanning the web for other runs.

“We just had the time of our lives,” she said, “going everywhere that we could drive to ultras. … I loved being out in the woods, being out on the trails.”

Soon, Sharon Mosley had dozens of ultra-marathons under her belt, and heading into this year that number, she estimates, had topped 50.

The Mosleys’ plan heading into the fall called for either Sharon or Joe — a coin toss was supposed to determine which — to run the Pine to Palm, which goes from Williams to Ashland, on Sept. 9, while the other stay at home with their injured dog, then they’d switch roles for the Javelina Jundred seven weeks later. Fate intervened, however, when wildfires forced the cancellation of the Pine to Palm. Sharon Mosley scrambled to find a replacement run: the Mountain Lakes 100. By then, Mosley had spent most of the previous three months at home taking care of their dog, so Joe scrapped the coin toss idea and asked Sharon if she’d like to stretch her legs in the Mountain Lakes 100.

She did, and had something else up her sleeve, too.

“Little did Joe know,” she said, “I had already signed up for (Rio Del Lago), which was the third of three races. And when I told him, he thought I was off my rocker. And, well, maybe I was home for so long, I was going stir crazy.”

Besides their sheer distances, each of the three ultras offered Mosley some unique challenges, and she overcame each to complete the Sharon Slam. At Mountain Lakes, she had to plow her way through slushy snow for about 23 miles. In Arizona, she celebrated her 55th birthday by running almost non-stop through 90-degree temperatures and no shade.

That set the stage for her big finish at Rio Del Lago. After Mosley crossed the finish line in Arizona, the next 100-miler was less than a week away. Rain and cold weather were in the Rio Del Lago forecast, meaning her body, besides another 100 miles, would have to endure a jarring change in climate, but by then she had already made up her mind.

“There wasn’t a possibility that I wasn’t going to do it,” Mosley said. “We got home Monday night at the airport, and we packed and took off early Friday morning and I was 100 percent. I know Joe didn’t think I could do it and that probably gave me more fuel. I had every intention of finishing that race.”

The race proved to be even more challenging than Mosley anticipated as she powered through the rain for roughly 15 hours. But she just kept putting one foot in front of the other, a lesson she learned from another Ashland ultra runner, Ben Benjamin, who inspired her years ago to stick with the sport, even after you don’t think you can take another step. Especially then.

After crossing the finish line, Mosley celebrated with her husband the same way they always do after completing a long race, by drinking a beer.

Asked if she’d like to try another tightly-packed trifecta some day, Mosley said she’s thinking about what the next challenge might be, but is hesitant to attempt another 100-mile run on only a week’s rest. In the meantime, she hopes her accomplishment inspires others the way Benjamin inspired her.

“I asked (Benjamin), ‘What gets you through the night?’” Mosley said. “He just presses on. He just walks and keeps walking. And so, when I’m out there at night and hoping an animal doesn’t get me, or anything else, and I’m all by myself, I just remember: just keep moving.”

Joe Zavala is a reporter for the Ashland Daily Tidings. Reach him at 541-821-0829 or jzavala@rosebudmedia.com. Follow him on Twitter at @Joe_Zavala99.