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How did she do it?

Mum, vet, Green Runner and the first woman to ever finish the infamous Barkley Marathons. How do women outperform men? Is the playing field a level one in ultramarathons?

Jasmin Paris in 2nd F, Glen Coe Skyline, Skyline Scotland (Credit: No Limits Photography)

Yesterday Jasmin Paris made history by becoming the first woman to cross the finish line in the infamously harrowing Barkley Marathons! The running world is flabbergasted at the achievement but Jasmin is no stranger to making history. In January 2019, she became the first person to cross the finish line in the 2019 Spine Race. What was remarkable was not that she obliterated the women’s record, but that she also took the overall record, winning outright - the first time for any woman in the history of this event.

Jasmin is a reserved and modest woman, so ‘normal’ but also seemingly superhuman; a relatable superhero. In truth, Jasmin's performance is one in a line of incredible performances and high-profile outright wins by female endurance athletes in recent years. Her achievement has added considerable fuel to the debate around whether women are better suited than men to challenging endurance running events. With women like Courtney Dauwalter, Nicky Spinks, Marianne Heading and Pam Reed catching the eye of the media, women are smashing through glass-ceilings left, right and centre. Are women simply comparatively better than men over very long distances?

It's often said that the difference in race finishing times between men and women lessens, the longer the running distance. But actually, that may not be the case. This week a campaign from SheRaces highlights data from RunRepeat that shows if anything, that gap is similar or even slightly bigger.

But over longer, complex multi-day challenges, there are simply so many more factors at play. While the physiological differences between men and women remain, the gap in performance may lessen due to other predisposing factors like pacing, preparation, self-care and sleep-deprivation. This is why we sometimes see historic achievments and even outright wins from incredible women!

Jasmin winning the Spine Race 2019. Credit: inov-8

“The rate of progress has been so rapid that statistically you might expect that at some point in the not-too-distant future, the gap will close and females will be better than males. But the physiological characteristics of men pre-dispose them to faster times in endurance races, and as a result the very best men will always beat the very best women” says John Brewer, Professor of Applied Sports Science at St Mary's University.

So what are these physiological limiting factors? Men have bigger hearts than women and also bigger lungs (by body mass), and therefore a higher VO2max. They have greater muscle mass, higher testosterone and a higher oxygen-carrying capacity (levels of haemoglobin in the blood).   Even in the face of these significant differences however, is there anecdotal evidence that women have an ‘aptitude’ for endurance? Many wonder whether it can be put down to differences in body fat, but this doesn’t seem to be the case. “Although women can have higher energy reserves due to a higher percentage body fat, even the leanest of males will have enough body fat to fuel around 40 consecutive marathons” says Brewer.

“Men actually have a higher maximum rate of fat oxidation (MFO), which has been correlated with improved endurance”, says Tracy Høeg MD, PhD, is Sports Medicine fellow at the Bodor Clinic in Napa, California and a world-class trail runner. “One example often quoted to support women’s superiority in challenging conditions is the very cold and rainy 2018 Boston Marathon. In this event, more men dropped out (5%) than women (3.8%) for the first time in history. This difference may be accounted for by the reduced rate of heat-loss in women, secondary to their higher percentage body fat. Certainly this same factor is a recognised advantage for women over men in long-distance open-water swimming challenges” says Hoeg.  “Research by Zingg et al from 2015 found that, the longer the ultramarathon, the better men do compared to women. In the longest ultramarathons, they found a gender gap of 15-20% in the top female finishers as compared to males.”

One might at least assume that the physiological disadvantage women face in endurance running is less than that which they would face in a shorter, faster race (where sheer power and strength are core factors in performance). But in fact, the opposite is true. Hoeg confirms that research from 2015 showed “the fastest men were ~17%–20% faster than the fastest women for all ultramarathon distances from, 50 miles to 3,100 miles*. But the gender gap is closer to 10% in shorter running races, with the difference for the 100m sprint being only 6.5%” says Hoeg.  

So maybe it’s just all in our heads? “There may indeed be some psychological reasons why females can do better than males over long distances” says Brewer, “as women have a tendency for more resilience and higher pain tolerance.” And perhaps it goes beyond that. Several ‘man-beating’ female athletes in the UK, including Nicky Spinks and Jasmin Paris have spoken openly in public about the importance of traits such as self-discipline, self-preservation, organisational skills and ‘tempering the competitive spirit’ during races as important factors which might predispose women to good performances in the most gruelling endurance events. “I think a woman is less likely to enter an event just because it claims to be the ‘toughest’. A women would be more likely to study the event in detail and think “I can do that”. Then she would go about making sure that she is well prepared,” says Nicky Spinks. “The key is to use your competitiveness to your advantage but not let it take over and ruin your race” she adds.  “Certainly, I went into the Spine Race thinking that it was possible I could win, but that was very much in the back of my mind and I didn’t start the race thinking solely about winning. I was more focused on my strategy,” said Jasmin Paris about her 2019 performance.

Sarah Rowell, Olympic marathon runner and high performance sports consultant, points out that “anyone who succeeds in long distance need these traits, whether they are male or female”. “I work in elite sport” she says, “and no athlete in any discipline will achieve top results unless they have all these characteristics”.

“As women we are used to looking after ourselves and other people in daily life and so naturally, we use this knowledge to look after ourselves well on the longer and harder races”.  “Perhaps it’s just the simple things. Maybe women are more likely to put on that extra-layer or pair of gloves earlier” says Nicky Spinks.

“While these ‘female traits’ might improve a given woman’s performance, I don’t anticipate these characteristics will ever eliminate the physiological gender performance gap” says Hoeg. “When Pamela Reed won the Badwater 135 Mile and Courtney Dauwaulter won the Moab 200 Mile, they did not disprove that the top men are on average at least 10% faster. However, their performances were phenomenal exceptions to the rule. In statistical terms, their performances are simply outliers. We mustn’t forget all of many ultramarathons run every weekend, which are routinely won by men. We humans tend to remember exceptions”.

“This is an important point for competitive women’s running because large ultramarathons with money prizes should, by this reasoning, always have separate podiums and equal prizes for men and women because physiologically and statistically women are not expected to be as fast (and certainly not faster) than men in these events. Each gender should be awarded equally and separately for their performances’, states Hoeg.

But what of motherhood? How does this gender-specific physiological change affect the performance of women as compared to men? Increasingly we are seeing images of mothers crossing the finish lines with their children in their arms or breastfeeding at refuelling stations. Just last year Sophie Power made headlines for completing the UTMB whilst breastfeeding her three-month-old baby. The same can also be said of Paris, who expressed milk for her daughter at the first checkpoint on the Spine Race. There is evidence that physiological changes induced by pregnancy may improve performance in the postpartum period, while some cardiovascular advantages may result in permanently improved endurance stamina in elite athletes.    

“Having my children is the best thing that has ever happened to me,” said Paris. “I feel fulfilled and have a new sense of perspective on the world. This makes me more relaxed and comfortable with myself, but at the same time more efficient and more focused - probably due to increased time constraints. I think this change translates into a mindset which you can carry with you into races” she says.

But it is possible that this focused mindset is not something limited solely to motherhood, but is a product of an organised mind and a busy lifestyle. In the infamous 2018 Boston Marathon, it was noted that second lady, Sarah Sellers (a complete unknown to the professional running world) was a nurse working demanding shifts around her training. The winner of the men's race, Yuki Kawauchi from Japan was also an amateur, and worked a 40-hour week as a government clerk, fitting in his training runs whenever he could.

Dr Hoeg also mentioned that “more high-quality research in female endurance sport is needed to bring better understanding and new insights, which can in-turn inform gender-specific strategies and further improve female performance.”

So are we going to see more women smashing expectations, breaking barriers and winning outright in endurance running events in the future? Well, the answers is (perhaps unexpectedly) yes!

It was not that long ago that women were prevented from taking part in endurance events, and the first female to run a marathon was Katherine Switzer in 1972. “As female participation increases, we should start to see the gender gap close until it reaches same ~10% we see in other disciplines, and we should eventually see this in even the longest ultramarathons. In fact, in terms of world records, Camille Herron has just recently lowered the gender gap in the 50 mile world record to 14.3% below the men’s, and in the 100 mile to just 9.7%” says Hoeg. As female participation increases, statistics dictate that we will witness proportionally more of these ‘phenomenal exceptions’ and see more women winning races outright to great acclaim.

If we want to achieve equity, whereby we see gender performance differences reflecting physiological differences, then the focus should be on encouraging increased female participation in ultrarunning and other endurance sports. According to a recent study, the global average for road marathon participation among women is 35%. Data suggest that this figure is lower for trail running, and lower again for ultra-distance trail or fell running.

“More women than men fear running on their own and running on unmarked trails” says Sarah Rowell. “The key is knowing your comfort zone and then being happy to push it little by little. Try and find races, events or training groups that allow you to do this.”

 One of the biggest barriers is fear of harassment, which is perhaps carried over from urban-trail or road-running, and the other is a fear of getting lost. Women typically have lower confidence in their navigational abilities than men' says Nancy Kennedy of Girls on Hills

 “Ultimately all that matters is that you’re enjoying it,” said Paris. “I wasn’t all that good when I first started but I’ve always just raced whoever I was near - wherever that was in the field. It just so happens that over time I have ended up competing with the men. Don’t limit yourself to an age or gender group, just go have fun and race your hardest!”

Jasmin and Nicky Spinks relaxing ahead of the UTMB. Credit: inov-8

“As a coach, I find that women sometimes don’t realise their own abilities. I encourage them to just give-it-a-go and they can really surprise themselves! I think women often put themselves second to work, life and family. All of which are important, but I’ve always believed that we only have one life and to make the most of it” concludes Nicky Spinks.

[This article is adapted from Are Women Narrowing the Gap in Ultrarunning? by Keri Wallace, Trail Running Magazine 2019].

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