Women in Ultra Running: Do Female Athletes Have an Endurance Advantage?

Discover why women are increasingly succeeding in ultra-endurance running and whether female physiology, pacing, and mental resilience could provide an advantage over extreme distances.

The Changing Face of Ultra-Endurance Running

For years, ultra-endurance running was often viewed as a discipline where male athletes would have the natural advantage. Men generally have greater muscle mass, higher aerobic capacity and greater strength, characteristics that can provide an advantage in many running events.

However, the picture becomes more complicated when races stretch far beyond the marathon distance.

Women are increasingly making their mark in some of the world's toughest ultra-endurance events. From 100-mile races to multi-day mountain challenges, female athletes are not simply participating. They are winning races, setting course records and challenging long-held assumptions about the limits of endurance.

This raises an intriguing question: could women actually have advantages when it comes to extreme endurance running?

The available evidence is interesting, although researchers stress that much more work is needed before firm conclusions can be reached.

The Performance Gap Changes as Distance Increases

In conventional running events, there is a noticeable performance difference between men and women. According to the source material, the average gap over distances up to the marathon is around 10% to 12%.

One explanation is physiological. Men generally have greater muscle mass and a larger aerobic capacity, which can contribute to faster performances over shorter and moderate distances.

Ultra-endurance races, however, place very different demands on the body.

When competitors are running for many hours, and sometimes several days, factors such as energy management, fatigue resistance, pacing and recovery become increasingly important.

Data referenced in the original BBC Sport report indicates that the performance gap becomes dramatically smaller in 100-mile races. Research involving more than two decades of amateur ultra-race data found a gender performance gap of approximately 0.25% at that distance.

At distances beyond roughly 195 miles, the data even suggests that women could potentially be faster.

This does not mean that women are universally better runners. Instead, it highlights how the characteristics needed for extreme endurance may differ from those required for shorter races.

Why Could Women Perform Well in Ultra-Endurance Events?

Researchers have suggested several physiological factors that could help female athletes during prolonged exercise.

1. Efficient Fat Metabolism

Women generally have greater levels of body fat than men. Although this might not appear beneficial for running performance, stored fat can provide an important energy source during prolonged exercise.

During very long events, athletes need to manage their energy carefully. The ability to use fat efficiently could potentially help preserve limited carbohydrate stores and provide a steadier source of energy over many hours.

This could become particularly valuable during races that continue through the night or extend across multiple days.

2. Muscle Characteristics

Another potential factor involves muscle fibre composition.

Women may have a greater proportion of oxygen-efficient, slow-twitch muscle fibres. These fibres are particularly suited to endurance activities because they can support sustained, lower-intensity movement for long periods.

Ultra-running is not simply about producing maximum power. Competitors must maintain movement for hours while managing fatigue, terrain and energy expenditure.

3. Resistance to Fatigue

Fatigue resistance may also be important.

The ability to maintain strength and performance as an event progresses could become increasingly valuable as runners move from 50 miles to 100 miles and beyond.

While these physiological differences are promising areas for research, scientists caution against treating them as established facts. There is currently considerably less research into female performance in extreme ultra-endurance events compared with shorter-distance running.

Mental Strength May Be Just as Important

Physiology is only one part of ultra-running.

Extreme races can involve sleep deprivation, unpredictable weather, difficult terrain, injuries, navigation challenges and prolonged physical discomfort. At that point, simply being fast is not enough.

Successful ultra-runners need patience, preparation and the ability to continue making sensible decisions when their bodies are exhausted.

Female athletes featured in the source material have highlighted adaptability and perseverance as important qualities.

Sophie Woods, for example, completed the Via Alpina while dealing with difficult conditions, route disruptions and very limited sleep. Her experience demonstrates that ultra-endurance success can depend on the ability to adapt when a carefully prepared plan stops working.

The same principle applies to nutrition, pacing and problem-solving. An athlete may need to change their strategy repeatedly during an ultra-marathon.

Pacing Could Give Female Runners an Edge

Another interesting area is pacing.

Long-distance races reward consistency. Starting too quickly can result in severe fatigue later, while overly cautious pacing can leave an athlete with unused energy.

Research discussed by sports dietitian Renee McGregor suggests that female runners may demonstrate more disciplined pacing strategies in distance events.

If female athletes are more likely to maintain a controlled pace rather than taking excessive risks early in a race, that approach could become increasingly valuable as distances grow.

Ultra-running rewards patience. The objective is not necessarily to be the fastest athlete during the opening miles. It is to still be moving efficiently when competitors begin to struggle.

The Role of Experience and Preparation

Mental resilience should not be viewed as something that automatically comes with being female. Individual personality, training, experience and preparation all play major roles.

However, McGregor suggests that women may develop valuable coping skills through experiences involving physical discomfort, hormonal changes, disrupted sleep and other demanding life events.

The broader lesson is that endurance is not simply a physical characteristic.

Training an athlete to cope with uncertainty, discomfort and fatigue can be just as important as improving their cardiovascular fitness.

More Women Need to Enter Ultra-Racing

One major obstacle to understanding female performance in ultra-running is participation.

Women currently represent only around one-fifth of participants at ultramarathon start lines, according to the source material.

That creates a significant research problem. If relatively few women compete in these races, researchers have fewer performances to analyse and fewer opportunities to understand how female athletes respond to extreme endurance conditions.

There are also wider barriers to participation. These can include social attitudes, concerns about safety, the time required for training and whether races provide appropriate support for female competitors.

Increasing participation could therefore benefit both athletes and researchers.

Female Success Could Inspire the Next Generation

Recent performances by women in major ultra-endurance races are already changing perceptions.

Jasmin Paris made history by becoming the first woman to complete the notoriously difficult Barkley Marathons, finishing with only a small amount of time remaining before the cutoff.

Other female runners have since achieved major victories and records in demanding events, providing visible evidence that women can compete successfully at the highest levels of ultra-endurance sport.

Visibility matters.

When aspiring runners see other women taking on 100-mile races, multi-day adventures and difficult mountain events, those challenges can begin to feel more achievable.

The growth of women's ultra-running may therefore create a positive cycle. More participation can lead to greater visibility, which can encourage more participation and ultimately provide researchers with better data.

What Does the Future Hold for Women in Ultra Running?

The idea that women could outperform men in extremely long endurance races is fascinating, but it should not be treated as a settled scientific conclusion.

The evidence suggests that the performance gap can become extremely small as race distance increases. Certain physiological characteristics, pacing strategies and approaches to fatigue may also potentially benefit female athletes.

Yet researchers acknowledge that the scientific evidence remains limited.

More women need to compete in ultra-endurance races, and more studies need to examine female athletes specifically. Only then will researchers be able to understand whether recent successes represent a genuine performance trend or simply the beginning of a much larger story.

For now, one thing is clear: women are proving that extreme endurance is not exclusively a male domain.

As participation continues to grow, the next decade could reveal just how far female ultra-runners can push the boundaries of human endurance.

Source: BBC Sport, Sarah Dawkins, 9 September 2026.

Disclaimer

This article is intended for general informational and educational purposes only. It should not be interpreted as definitive scientific evidence that women are better endurance runners than men. Individual athletic performance varies considerably according to training, genetics, experience, health, nutrition, environmental conditions and many other factors. Readers should consult qualified sports, medical or scientific professionals for advice relating to their individual circumstances.