Ask most people to picture an ultra marathon winner, and they will picture a man. The reality of what happens when races stretch beyond 50 miles tells a very different story. At the longest distances, women do not just compete with men; they frequently beat them outright. This is not an occasional anomaly. It is a pattern supported by physiology, psychology and race data from events around the world, and it is something I have watched play out repeatedly in the runners I know, coach and train with.

Understanding why women excel at ultra distances is not just fascinating; it has practical implications for how women should train, fuel and pace themselves for long-distance events. If you are a woman considering your first ultra or wondering whether the distance suits you, the science suggests it almost certainly does.

And if you want to see this in action right now, Courtney Dauwalter has just finished second woman and sixth overall at the 2026 Cocodona 250, a 253-mile race through Arizona. After a DNF last year, she came back and ran 250 miles through the Arizona desert. Everything in this article explains exactly why she did it. And that’s not even taking into consideration that it was won by Rachel Entrekin, beating the previous men’s record in a little over 56 hours on 19 minutes sleep! And. let’s not forget the outstanding performance of Jasmine Paris at the Barkley Marathons in 2024 when she became the first woman to complete this bonkers event. We could go on…

The Physiology of Ultra Endurance

Fat-burning efficiency

The single biggest physiological advantage women have in ultra marathon running is their ability to use fat as a fuel source more efficiently than men. At ultra distances where glycogen stores are repeatedly depleted and replenished over many hours, a runner who can access fat stores more readily has a profound endurance advantage.

Research consistently shows that women oxidise fat at a higher rate than men during prolonged exercise at submaximal intensities. In practical terms, this means women are less dependent on carbohydrate fuelling strategies, experience less dramatic energy crashes and maintain a more consistent energy output over very long distances. The wall that male ultra runners hit is partly a glycogen problem. Women hit it later and less severely.

Muscle damage and recovery

Women experience less exercise-induced muscle damage than men during ultra-distance events. The reasons are not fully understood, but oestrogen appears to play a protective role in muscle cell membranes, reducing the inflammatory response to prolonged exercise. This means women typically experience less severe muscle breakdown during a race and recover more quickly between stages in multi-day events.

In a 100-mile race where the final 30 miles are run on legs that are already significantly damaged, this advantage is enormous. Male runners who were faster in the first half frequently find women they passed in the early miles overtaking them in the final third of the race as muscle fatigue accumulates differently.

Heat management

Women generally have a higher surface area to body mass ratio than men, which makes heat dissipation more efficient during prolonged exercise. Ultra marathons in warm conditions favour runners who can manage core temperature effectively over many hours. Women’s physiology handles this more efficiently, which becomes increasingly significant as race duration extends.

Pain tolerance and discomfort management

The research on sex differences in pain tolerance is complex and contested, but several studies suggest women may have a higher tolerance for the specific type of sustained discomfort that ultra marathon running produces. This is distinct from acute pain tolerance — it is about the ability to continue functioning at a high level while experiencing significant physical discomfort over many hours. Ultra running is essentially a prolonged exercise in discomfort management, and women appear to be well-suited to it.

The Psychology of Ultra Performance

Physiology alone does not explain the pattern. The psychological profile of successful ultra runners; patience, conservative pacing, emotional regulation, the ability to manage low points without panicking, matches traits that research associates with women consistently more than men.

Pacing discipline

The most common reason male ultra runners underperform relative to their ability is going out too fast. The competitive instinct to lead early, to respond to other runners around them and to run at a pace that feels sustainable in the first hour but is not sustainable over 50 or 100 miles is a pattern I see repeatedly in the runners I coach. Women are statistically better at running even splits in ultra events — starting conservatively, managing effort through the middle miles and finishing strongly relative to their early pace.

At the longest distances, this pacing advantage compounds dramatically. A runner who goes out 10% too fast in a 100-mile race does not just lose that 10% — they may lose 30 or 40% of their potential in the final quarter of the race as the early effort debt is repaid with interest.

Emotional resilience during low points

Every ultra marathon involves low points — periods where everything hurts, motivation disappears and the idea of continuing feels genuinely impossible. How a runner manages these periods determines more of their race result than almost any other factor. Women tend to approach these low points differently to men — with more patience, more willingness to slow down temporarily rather than fight through at unsustainable effort, and more ability to reframe the experience positively and keep moving.

Ego and decision making

This is uncomfortable to say directly, but the data supports it. Male ultra runners are more likely to make ego-driven decisions during races — pushing through warning signs, refusing to slow down when they should, competing with other runners around them rather than running their own race. These decisions cost time and sometimes result in DNFs. Women are statistically less likely to make these errors at ultra distances, which translates directly into better race outcomes relative to their training fitness.

What the Race Data Shows

The pattern shows up most clearly at the longest distances. At marathon distance, men are significantly faster than women on average. At 50k, the gap narrows. At 100 miles and beyond, the gap narrows further, and at the very longest ultra distances, women frequently outperform men outright rather than just closing the gap.

Research consistently shows that the performance gap between women and men narrows progressively at longer ultra distances. A large-scale study analysing over 300,000 race records in 50-mile and 100-mile events found the sex difference in finishing times was significantly smaller in 100-mile races than in 50-mile races, and that women reduced the gap further with age. At the very longest distances, multi-day events and timed ultras, the gap narrows to the point where women regularly match or beat men outright [1].

Jasmin Paris won the Spine Race outright in 2019 in a course record time, beating every male competitor while stopping to express breast milk at checkpoints. These are not outliers. They are the visible expression of a pattern that plays out across ultra running globally. And Courtney Dauwalter, finishing second woman and sixth overall across 250 miles of the Arizona desert in May 2026, is the most recent example.

What This Means for Women Training for Their First Ultra

If you are a woman training for your first ultra marathon the science gives you some very specific and practical guidance.

  • Train for fat burning. Long slow runs at genuinely easy effort, conversational pace, well below threshold, train your body to access fat stores efficiently. Many women make the mistake of running their easy runs too hard, which suppresses fat oxidation. Slow down on your easy days, and you will perform better on race day.
  • Practise your pacing. The single most important race day skill is starting slower than feels comfortable. If the first miles feel easy, you are probably pacing correctly. If they feel like a comfortable effort, you are probably going too fast for an ultra.
  • Trust your strengths. The discomfort of an ultra is something your physiology and psychology are well-suited to handling. The low points will come; they come for everyone, but your ability to manage them is genuinely one of your greatest assets as an ultra runner.

See our 50k ultra training plan for a structured approach to building your ultra fitness. And for the kit you need to run your first ultra, see our guides to the best trail running vests and best Garmin watches for trail running for tracking your training and pacing your race.

Kit for Women Running Ultras

Getting your kit right matters more in ultra running than at any shorter distance. Here are the key pieces worth investing in.

Trail shoes that fit properly

Foot swelling over ultra distances is significant — feet can increase by half a size or more during a 50-mile race. Wide fit shoes become even more important at ultra distances than at shorter ones. Shoes that feel fine at mile 10 can become genuinely painful by mile 40 if the fit is compromised.See our guide to the best wide fit trail shoes for women for our current top recommendations; the Hoka Speedgoat 7 Wide and Altra Lone Peak 9+ are both excellent choices for ultra distances specifically.

A running vest that carries everything you need

At ultra distances, you carry mandatory kit, nutrition, water and layers. A well-fitted running vest that sits securely without bouncing is essential. See our best trail running vests guide for options that work well for women specifically.

A GPS watch for pacing and training

At ultra distances, you carry mandatory kit, nutrition, water and layers. A well-fitted running vest that sits securely without bouncing is essential. See our best trail running vests guide for options that work well for women specifically.

Frequently Asked Questions

Do women really beat men in ultra marathons? At the longest distances, yes, the performance gap between men and women narrows progressively as race distance increases, and at 100 miles and beyond, women frequently outperform men outright. The pattern is well documented in race data and supported by physiological research.

Why do women perform better at longer distances? The main reasons are greater fat burning efficiency, less exercise-induced muscle damage, better pacing discipline and stronger emotional resilience during low points. These advantages become more significant as race distance increases.

What is the longest distance where women have beaten men outright? Jasmin Paris won the Spine Race — 268 miles across the Pennines — outright in a course record time in 2019. Courtney Dauwalter finished second woman and sixth overall at the 2026 Cocodona 250, covering 253 miles through Arizona. At multi-day and extreme ultra distances, women regularly beat or match men in overall results.

Should women train differently from men for ultra marathons? The broad principles of ultra training apply equally to both sexes. Women may benefit from placing extra emphasis on easy aerobic running to train fat-burning efficiency and from being particularly conservative with early race pacing. Recovery needs may differ across the menstrual cycle, and training loads should be adjusted accordingly.

Is fell running good preparation for ultra marathon running? Excellent preparation; the hill fitness, descent technique and mental toughness developed through fell racing translate directly to ultra marathon performance. Many of the UK’s strongest ultra runners have a fell racing background. See our guide on how to train for your first fell race if you want to add fell racing to your training.

References

  1. Nikolaidis PT, Knechtle B. Women Reduce the Performance Difference to Men with Increasing Age in Ultra-Marathon Running. Published in PMC 2019. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6651135/