Anne Flower had no idea she was on the verge of breaking one of the most historic records in running until she had already run almost 99 miles of Colorado’s Leadville 100 this past weekend (16 August 2025).

It was the first 100-mile race Flower had ever run…

It was only when the 35-year-old emergency room doctor from Colorado Springs passed Justin Grunewald to move into second place overall, less than two miles from the finish line, that she learned Ann Trason’s 1994 women’s course record of 18:06:24 was actually within reach. It was the first 100-mile race Flower had ever run, so she said she had been trying to run her own race, maintain effective fueling and hydration, and just avoid falling.

Flower put in one final surge in the homestretch on the last hill along 6th Street in Leadville, and sprinted across the finish line in 17:58:19, breaking Trason’s previous mark with more than eight minutes to spare as the late-night crowd of about 200 people lining the finish chute cheered in approval.

Trason, an all-time ultrarunning legend who won the Western States 100 a record 14 times and the Leadville 100 four times during her career, set that mark 31 years ago while racing against several male Tarahumara runners from Mexico.

Flower’s Race Preparation

Flower won the Leadville Trail Marathon and Silver Rush 50-miler earlier this summer in Leadville and earned an entry into the Leadville 100, but only decided to go ahead and run it two weeks ago. She hadn’t been training specifically for it, but she said she’s been as fit as she’d ever been, so she figured she should give it a shot.

“I feel like I shouldn’t be in the same category as Ann Trason. She’s a goddess of running,” Flower said after finishing. “I was running my own race, especially at the start, because there were a few ladies who went out faster than me, and I knew I had to keep it controlled. I knew (the record) was low and I honestly thought it was in the 17s, but when we were coming up the boulevard, Justin and his partner told me it was 18:06, so I thought I should probably get it done.”

Flower didn’t take the lead in the women’s race until about mile 25, when she was seventh overall in the race. She ran the first 87 miles solo, but then was joined by pacer Gil Allgood at the May Queen aid station on the west side of Turquoise Lake for the final 13 miles back to Leadville.

Leadville 100 Background

The entire 100-mile course is at or above 9,200 feet above sea level, but the crux of the course entails going up-and-over 12,600-foot Hope Pass twice between miles 40 and 60. Flower averaged a 10:47 mile pace over the entire course, but ran under an 8-minute pace on many of the flatter sections.

Only two runners had come within an hour of Trason’s record before this year. Claire Gallagher had been the first one to get close when she won the race in 19:00:27 in 2016, but then Mary Denholm came even closer when she won last year in her debut 100-miler in 18:23:51. Imogen Ainsworth, 37, from Poncha Springs, Colorado, was the second woman to finish, placing seventh overall in 19:36:42. Two other women finished in the top 10 overall: Lea Mulligan, 26, from Chattanooga, Tennessee, (9th, 20:39:04) and Genevieve Harrison, 38, of Eagle, Colorado (10th, 20:57:23).

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