The 131 runners at the Dragon’s Back Race briefing in June 2015 were nervous enough about the next five days. Namely attempting to cover 300K and 16,000m of ascent as they ran down the middle of lumpy Wales. But the females were about to feel slightly less so.

Helene Whitaker (neé Diamantides), joint overall winner of the 1992 race and women’s winner of the second version in 2012, told the gathering: “If you’re female, you’re three times more likely to finish this race.”

This writer wasn’t the only male to shift uncomfortably in his seat. Most men know it, but we don’t like to admit it. Despite the seemingly macho distances involved, women are better at running ultramarathons.

Ultras are different. The distances are often so huge – from anything above the classic 26.2 miles right up to the frankly loony Self-Transcendence 3,100 Mile Race – that simply finishing is the target for most. Look at the results of almost any ultramarathon and, compared to men, a greater percentage of women who start a race finish it. In Born To Run Christopher McDougall notices the same trend and asks: “How come nearly all the women finish [the notorious US 100-miler] Leadville and fewer than half the men do?”

Due to age-old biological disparities between the sexes – men tend to have higher VO2 max for example – women are less likely to win. But they’re also far less likely to give up and drop out (DNF). Following that logic, the female of the species is more successful at running ultramarathons. It could even be the closest thing there is to a gender neutral sport.

Physicality

When it comes to endurance, women have several inherent advantages over men. “Women generally have a larger surface area to mass ratio, which enables heat to dissipate more easily,” says running coach and movement specialist Shane Benzie from Running Reborn.

“This means women are generally better at coping with heat,” explains ultrarunner, registered dietician and sports nutritionist, and Training Food author Renee McGregor. “A smaller athlete tends to have lower fluid losses due to smaller surface area.” So they’re less likely to become dehydrated. A lighter runner is carrying less weight and therefore stressing the body less.

A shorter runner also benefits. “Shorter legs are often seen as an advantage,” says Benzie, “as they are more suited to a quicker turnover, and a faster cadence will ensure efficient use of the elastic energy created during our running stride.” Some also believe

that in long races with more descent, a smaller physique incurs less muscle damage on downhills – quads are the place most ultrarunners feel soreness first. That means (in theory) a shorter runner will move more comfortably later in a race. Diminutive Lizzy Hawker, five-time women’s winner of UTMB, a 104-mile race in the Alps with 10,000m ascent, is a prime example of this.

Fat metabolism is another key factor that favours females. In The Complete Book of Running for Women, Claire Kowalchik writes that women use about 75% more fat than men while running. “Women generally burn a higher percentage of fat compared with men,” agrees Renee McGregor. This means consistent and almost limitless energy release, while ‘bonking’ or hitting ‘The Wall’ comes more naturally to more carb-dependent men – especially as they’re likely to run faster (more anon). “It’s also been shown that women are better at using exogenous sources of carbohydrate compared to men,” says McGregor. “So even if glycogen stores are full, they tend to use available carbohydrate from exogenous sources more efficiently.”

Mentality

Another key aspect – perhaps the key aspect – is pacing. A RunRepeat study of more than 1.8 million marathon results from all over the world spanning five years, concluded women are better at men at maintaining a consistent pace. They slow down 18.61% less than men in the second half of a marathon. The cause, reported Danish statistician and former competitive runner Jens Jakob Andersen, is that men tend to believe “a bit too much” in their abilities and therefore start out too fast.

“DNF excuses such as cramping, injury, nutrition and dehydration are often down to poor pace judgement,” says Debbie Martin-Consani, a GB international ultrarunner. Ultramarathons are the sport where the tortoise usually beats the hare. Women, and tortoises, are simply more sensible. Which makes them more successful.

“The longer the race, the greater the chance for women to shine,” says Ian Corless, publisher of the Talk Ultra podcast and a photographer often found clicking away at ultramarathons. “Watch any ultra and men charge off the front and the ladies play it cooler. When the men drop out through exhaustion, the ladies come running by looking fresh as a daisy.”

In ultras, confidence is a complex thing though. When Hewlett-Packard wanted to see why more women weren’t in top management positions they commissioned research and made an interesting discovery. Women applied for a promotion only when they believed they met 100% of the qualifications listed. Men were happy to apply when they met 60% of the requirements. Apply that hypothesis to ultramarathons and female runners won’t have signed up for an ultra unless they feel they are fully qualified. Whereas men are more likely to sign up with bravado than a relevant running background.

Helene Whitaker thinks women’s comparative lack of confidence benefits them. “Most women don’t have a huge amount of self belief and esteem,” she says. “So any woman stood on the start line of a daunting event will have done her homework, prepared hard and will therefore have a greater chance than most men of completing it.”

Whitaker also thinks women tend to be more detail orientated. “They spend time and effort getting the small things right. Navigation, food, heart rates, foot care; the nitty gritty that make or break over large distances. Call us control freaks, but ultrarunning is all about being in control. The gender differences were evident on the 2015 Dragon’s Back race again. None of the female runners were in distress. Some were perhaps slow, but all competing within their own, known, tried and tested abilities.”

Levels of confidence in female runners may be a double-edged sword however, as participation in ultramarathons is still comparatively low for women. The same thing that makes them so successful means many may be too daunted to try them in the first place. This could also be social and cultural.

“Many of the stronger women in today’s running are groundbreakers,” says ultrarunner Carol Morgan, who’s completed the Dragon’s Back Race and won both the Lakeland 100 and the Fellsman ultramarathons. “I suspect for many female ultrarunners, behind the soft facade, the smiles and the enjoyment lies a determination to succeed – the historical knowledge that we’ve been overlooked, both individually and as a sex, driving us on to succeed where we were told we wouldn’t and couldn’t.”