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The Increasing Competitiveness of Women’s Ultrarunning

A statistical analysis of the increasing competitiveness of women’s ultrarunning, using the 2023 Western States 100 as a case study.

By on July 26, 2023 | Comments

When Courtney Dauwalter crossed the finish line of the 2023 Western States 100 in a course record-setting time of 15:29, she made a powerful statement: women’s ultrarunning has leveled up. In this month’s column, I make that same statement, but less powerfully. I’ll use graphs instead of world-class athleticism.

Rolling into this past June, our plan at iRunFar was to use the July edition of this Running the Numbers column to launch a multi-part series featuring remarkable mountain running, ultrarunning, and trail running performances that can be better appreciated with quantitative data. In the wake of the Western States 100, a natural theme emerged for this article: the increasing competitiveness of women’s ultrarunning. It’s a trend that many of us are already tracking and discussing, so let’s use a selection of data to add another layer to these discussions.

2023 Western States 100 - Courtney Dauwalter - course record

Courtney Dauwalter setting a new course record at the 2023 Western States 100. Photo: iRunFar/Meghan Hicks

Fast Paces from Mile One

Jackie Merritt’s performance at the 2017 Western States 100 was a seminar in smart pacing. As Ryan Witko pointed out in his “Statistical Guide to the Silver Buckle,” the statistical probability of Merritt finishing the race in under 24 hours that year was only 19% when she came through the first aid station (at mile 10.3) at a conservative pace. Not only did Merritt ultimately get the coveted silver buckle the event gives to sub-24-hour finishers, she passed other women all day and raced her way to seventh place. She demonstrated mastery of a racing strategy that was considered highly effective for this event at that time: allowing some of your competitors to get slightly ahead of you in the early miles, knowing you could chase them down somewhere after the Foresthill aid station at mile 62.

While Merritt-level fitness and top-10 finishes never go out of style, the racing strategy she perfected offers fewer advantages in 2023 than it did in 2017. As others have pointed out already (it was discussed on the Singletrack podcast with reference to a post on Twitter by @aidstationfireball/Liam Tryon), eight of the first 10 women through the Foresthill aid station (mile 62) this year ultimately finished in the top 10. Keely Henninger dropped from the race at mile 80 with a dislocated shoulder, while Leah Yingling and Meghan Morgan eventually passed Jenny Quilty, who went on to finish in 11th place. In 2023, it would seem, there were fewer opportunities for late-in-the-race passing. The fastest runners were too far ahead of their chasers, and we didn’t see significant bonking or blowups. Favorable temperatures may have resulted in relatively fewer blowups in 2023, and I’m curious to see if pacing strategies at the Western States 100 evolve to become increasingly aggressive from the start line.

2023 Western States 100 - Leah Yingling - Eszter Csillag - Meghan Morgan

Leah Yingling, Eszter Csillag, and Meghan Morgan running together at Robinson Flat (mile 30) during the 2023 Western States 100. Photo: iRunFar/Jaja Ferrer Capili

Larger, Faster Chase Packs

Let’s get back to the impressive Jenny Quilty. If we’re looking for proof of how competitive the Western States 100 women’s race has become, think about how fast you have to be now, just to come in 11th. Given the prestige and automatic entry to next year’s race, finishing in the top 10 is a big deal for competitive runners. Over the years, many 11th-place finishers have conceivably felt like “first loser.” But when Quilty crossed the finish line in 18:49:13, she clocked the 64th-fastest women’s finish ever at the event, and the fastest-ever 11th-place finish. For added context, the chart below shows what that finishing time would have earned Quilty in any previous edition of the event (that had women’s finishers). And if that isn’t powerful enough, let me put it this way — while temperature and course conditions play a factor in finishing times in any year, Quilty’s 2023 time was faster than some of Ann Trason’s winning times.

Jenny Quilty - 2023 Western States 100

Jenny Quilty running in ninth at Robinson Flat at the 2023 Western States 100. She would go on to finish 11th. Photo: iRunFar/Jaja Ferrer Capili

Competitiveness of Women's Ultrarunning - Quilty pie chart

The pie chart shows that, in the women’s field, a finishing time of 18:49 has historically been fast enough to at least get the finisher on the podium, or even the win. As recently as 2017, which was considered a hot year, the winning time was slower than Jenny Quilty’s 2023 11th-place time. Cat Bradley won the 2017 Western States 100 in 19:31:30.

Blazing Fast Times

Admittedly, Courtney Dauwalter’s result requires very little context for us to appreciate its significance. She won one of the most prestigious 100-mile races, and ran it significantly faster than any other woman in the history of the event. But hold my drink, I still want to point to some statistics for comparison. “UltraRunning” magazine’s annual year-in-review edition publishes a roundup of the fastest 100-mile finishes, by gender, from the previous year.

The list is typically dominated by results at relatively fast and flat 100-mile races, like the Desert Solstice Invitational, Rocky Raccoon, Tunnel Hill, Hennepin, and Javelina. Javelina and Rocky Raccoon are the “hilliest” of those races, with roughly 5,200 feet (1,585 meters) of elevation gain each over 100 miles, compared to 18,090 feet of elevation gain at the Western States 100. That is to say that it would be unusual to find a result from the Western States 100 on this list.

But here we are, and Dauwalter’s 15:29 finish at the Western States 100 would have been the 12th fastest 100-mile time among women in North America in 2022, based on “UltraRunning” magazine’s list of top 100-mile times. From 2020 going back to at least 2014, Dauwalter’s time would have been in the top five every year.

And Dauwalter is by no means a one-off. Katie Schide finished second at this year’s Western States 100 and also ran under the previous course record.

Camille Herron ran 100 miles in 14:41 at the 2023 Sri Chinmoy 48 Hour Festival in Australia, and then kept running to ultimately cover more than 270 miles in 48 hours – a new world record. For perspective, “UltraRunning” magazine only recorded 13 results faster than her 100-mile split between 2017 and 2022, and six of those times were set by Herron herself.

Camille Herron - 2023 Sri Chinmoy 48 Hour Festival

Camille Herron at the 2023 Sri Chinmoy 48-Hour Festival. Photo: Sri Chinmoy 48 Hour Festival

Are the Women’s Races Becoming More Competitive at All 100 Milers?

I got curious as to whether this new level of competitiveness applies to other races as well. For this round, I decided to limit my attention to the women’s fields of 100-mile races in North America.

I turned to a dataset that “UltraRunning” magazine generously provided, which consists of a large sample of finisher numbers and winning times for ultramarathons in North America since 2012. Because the dataset only lists the finishing time for each event’s male and female winners, the best I could do to measure competitive performance by the women’s winner was to calculate their finishing time as a percentage of the men’s winning time. From there, I calculated the average for races of a given distance for each year.

As you’ll see in the chart below, the gap between women’s and men’s finishing times was, on average, similar in 2012 and in 2022. There are multiple possible explanations for this. For example, a fast women’s winning time won’t stand out here if it happened alongside a fast men’s winning time. It may also be that the women’s field is less competitive in many events, bringing down the average.

Competitiveness of Women's Ultrarunning - Women's wins as percentage of men's

The line graph shows the average, per year, of the women’s winning time for every 100-mile race in a dataset provided by “UltraRunning” magazine, when the women’s winning time is expressed as a percentage of the men’s winning time. A smaller percentage indicates a smaller gap between the men’s and women’s times.

To look at these data points differently, I calculated what percentage of races per year saw the women’s winner finish within 15% of the men’s winning time. I chose 15% as a somewhat generous ratio, inspired by research indicating the mean gender-based performance gap in running sports is 10.7%. I figured, for the sake of argument, that if the women’s winner of a particular 100-mile race finished within 15% of the men’s winner’s time, that runner had maximized their performance to a degree that was at least generally comparable to the men’s winner. If the women’s winning time was significantly less than 15% of the men’s winning time, then we might say that runner maximized their potential to a greater degree.

This time, we see there appears to be an increasing proportion of 100-mile races where the women’s winner finishes within 15% of the men’s winner’s time. Based on the “UltraRunning” magazine dataset, 2022 was a record year for the proportion of races where women were finishing fairly close to or ahead of the men’s winners.

Percentage of 100-mile races where women's winning time was within 15% of men's winning time

The line graph indicates that, at an increasing proportion of 100-mile races, women are finishing within 15% of the men’s winning time. This trend has been especially pronounced since 2020.

I was conflicted about using this metric to attempt to quantify women’s performance improvements. I wanted to draw on a large dataset to look for trends across many events and years. But I also recognized that each event includes a men’s race and a women’s race, so it can be problematic to measure women’s winning times relative to men’s winners’ times, instead of comparing women’s winners to their competition.

Looking for other ways to measure competition in women’s fields, I compared the podium spread at some of the most prestigious 100 milers in the United States. I measured the third-place finisher’s time as a percentage of the winner’s time. If each race is getting more competitive, the spread should be shrinking as the third-place woman finishes on the heels of the winner.

As you’ll see in the chart below, there isn’t a clear trend. Interestingly, this metric suggests the Western States 100 and Cascade Crest 100 Mile were both less competitive in 2023 than in 2018. In fact, these events had the same respective winners in both of those editions — Courtney Dauwalter at Western States and Yitka Winn at Cascade Crest. Both runners improved on their winning times from 2018. So, while both events had faster third-place finishers in 2023, Dauwalter and Winn’s fast times still increased the podium spread.

Women's podium spread by 100-mile race

The bar graph shows the women’s podium spread at eight American 100 milers. A long bar indicates that a relatively large amount of time separated first and third places at a particular event. A short bar indicates first and third place finished relatively close together, which suggests a more competitive race. The graph shows the most recent edition of each event, plus results from five years previous, to offer insight on whether a race has become more competitive in recent years.

I was also struck by how, among these races, there was no guarantee that the most recent winning times would be faster than the winning times from five years before. I should have known that course records aren’t being set every year at every race. In the table below, I calculated the degree to which the women’s winner improved on the winning time from five years before. Negative numbers indicate races where the women’s winner was faster in 2017 or 2018 than in the latest edition of the race.

Competitiveness of Women's Ultrarunning - 100-mile race - winning time comparison

The table lists eight 100-mile races in the United States, with a percentage for each event. The percentage compares the women’s winning time at the most recent edition of each race to five years’ previous. A positive number means the women’s winner was faster than five years ago. A negative number means the most recent winner was not faster than the woman who won five years before.

Closing Thoughts

My preliminary examination of the data suggests that the Western States 100 women’s field is significantly more competitive than the women’s field of any other American 100 miler. Will that change in the years ahead? Statistics from “UltraRunning” magazine show women’s participation/finish rates at North American ultramarathons is trending upward. As the likes of Courtney Dauwalter and Jenny Quilty inspire those runners, we’re likely to see more course records and hard-fought podium finishes at races across the continent.

Competitiveness of Women's Ultrarunning - Women as a percentage of finishers

The line graph shows the percentage of female finishers at North American ultramarathons, as reported by “UltraRunning” magazine. The data is grouped by race distance, to acknowledge participation and finisher rates vary by distance. “UltraRunning” magazine also tracks these statistics for timed races and backyard ultras. We decided to exclude those categories from the graph because there are significantly fewer events and participants in those disciplines.

Call for Comments

  • Are there other examples you’d call on to highlight the current state of competitive women’s ultrarunning?
  • Since this article was inspired by the Western States 100, it’s specific to 100-mile races in the United States. Do you think these trends extend to other regions or race distances?
Mallory Richard

Mallory Richard is a data analyst and trail runner in Winnipeg, Canada.