Why do women win ultras

Last updated: 19-Jul-18

By Alice Morrison

There are very few sports where, on the day, a female athlete comes out on top and wins outright. There are very few sports where women and men compete in the same race or competition side by side. Horsemanship is one of them with women as equal competitors, but the biological playing field is levelled there by the horse. One of the great things about ultra running is that, in most races, you all set off together without regard for gender, age or ranking. So, what is behind this truth that women can beat their male counterparts and win ultras?

The poster girl for this, of course, is Pam Reed who won Badwater in 2002 and 2003. Badwater is not an easy race. It describes itself as “the world’s toughest foot race” as does the Marathon des Sables. It is a 217 km course starting at 85 m below sea level in the Badwater Basin, in California’s Death Valley, and ending at 2548m at Whitney Portal, at the head of the trail to Mount Whitney. It takes place annually in mid-July, when the weather conditions are most extreme and temperatures can reach a whopping 130 °F (54 °C). 

Placing limits on what I think I can accomplish is something I tend not to do. I’ve heard that people are actually able to cover about twice their imagined limit: If you think you can run only 1 mile, you can really run 2; if you think you can run 2, you can run 4. You might not be able to cut your ‘best’ time in half, but you can reduce it by a significant percentage. That has been my experience. While initially I never thought I would run the distances I have, or in the times in which I’ve done them, I haven’t really put mental limitations on myself either. And truly, I’ve surprised myself,” says Pam.

A number of reasons are proffered if you ask the question, “Why do women win ultras?” to any ultra running group. Two things that tend to come up time and again are that women burn fat differently from men which advantages them in very long endurance events and their pain threshold is higher. Is there any evidence to support these theories?

Gender Differences

In society generally, the focus tends to be on losing weight and fat, not retaining it, whilst in ultras, not using up all your body’s reserves and metabolising them more slowly is an advantage.

Blood glucose and muscle glycogen are essential for vigorous and prolonged strenuous exercise. Exhaustion during exercise is highly influenced by the development of hypoglycaemia (low blood glucose) and depletion of muscle glycogen. 

Looking first at the rate and amount of carbohydrate (via glucose and glycogen) used during exercise by women, a study by Len Kravitz, Ph.D., Afton Cazares, M.A., Christine Mermier, Ph.D. 
finds that:

In respect to female utilization of glucose and glycogen during endurance exercise, the consensus in the research suggests there is a lower glucose appearance and slower rate of glucose disappearance in women, as compared with men during endurance exercise (Tarnopolosky 2008). Tarnopolosky, in his research review, summarizes that the research indicates this may be a result of a lower sympathetic (nervous system responsible for the fight-or-flight response) nervous activation in women, and not due to the ovarian hormones. Tarnopolosky continues that slightly inhibited carbohydrate utilization during endurance exercise observed with women is also reflective of hormonal influences affecting fat metabolism.

The role of fat

It is well established that women generally have a higher percentage of body fat than men. A healthy range of body fat for women is 20-25%, and a healthy range of body fat for men is 10-15% (Robergs and Roberts, 1997). 

During endurance exercise, fuel source and the use of it plays a primary role in performance. The contribution and expenditure of fat during exercise is regulated by several factors, including gender. Interestingly, before puberty, there is no difference between males and females when it comes to substrate usage during exercise (Isacco, Duché and Boisseau). But after puberty women rely more on fat than men for the same relative intensity of exercise.

Pain threshold

Does it really exist and if it does is it different for men and women? I went to WebMD for the basics:

Pain is both a biochemical and neurological transmission of an unpleasant sensation and an emotional experience,” Doris Cope, MD, an anaesthesiologist who leads the Pain Medicine Program at the University of Pittsburgh Medical Center, tells WebMD. “Chronic pain actually changes the way the spinal cord, nerves, and brain process unpleasant stimuli causing hypersensitization, but the brain and emotions can moderate or intensify the pain.” Past experiences and trauma, Cope says, influence a person’s sensitivity to pain.

That would indicate that pain is experienced differently by each individual. A recent review of the research into gender and pain has given conflicting evidence but makes for interesting  reading. One area that gives concrete results has to do with how the genders process pain. In this study they found that women recruit their emotions while men recruit their threat-control circuits:

Results revealed that subjective pain unpleasantness was strongly associated with increased perigenual anterior cingulate cortex activity in women, whereas it was strongly associated with decreased ventromedial prefrontal cortex activity in men. Only ventromedial prefrontal cortex deactivations in men were additionally associated with increased autonomic cardiac arousal. These results suggest that in order to deal with pain’s objectionable properties, men preferentially deactivate prefrontal suppression regions, leading to the mobilization of threat-control circuits, whereas women recruit well-known emotion-processing areas of the brain.”

Ultra runners’ thoughts

I was also interested to reach out to hear the opinions of committed ultra runners.

Caolan MacMahon: “As distances get longer, VO2Max differences matter less. Being able to utilize fat matters, and toughness of mind matters. At ultra distances (50+ miles) women are on a more equal ground physiologically, and mentally may be better able to deal with things. Still women are a vast minority in ultra distances – and my guess is that women are less likely to jump into these things until they know they are ready. I think that may be changing with all the ultra hype, but you should compare women’s DNF rates to men’s in tough races. In the past women’s DNF rates were lower on average.”

Rob Leder: “Women sometimes take the overall at short distances, too. I’ve certainly seen good female runners win 5ks outright. But if you look at world records, there doesn’t seem to be much evidence that the performance differential between sexes decreases with distance. It all depends on field size and who decides to show up. In terms of the depth and level of competition, the majority of ultras are a lot more similar to local road races than they are to, say, the Boston Marathon. But it seems very unlikely that a woman will ever cross the line first overall at Comrades or a 100k world championship.

Bernadette DePerty DuBois: “The same hormone that is responsible for aggression, dominance, and sex drive, can work against a man when it comes to being patient and thinking things through, which you kinda need in ultras.

Michele Hammond: “My husband & I both run & when it comes to trail races the marathon distance seems to be the dividing line & the place where I start to beat him. I think in many cases I can just go for more hours with less specific aches & pains or maybe I’m more able to tolerate the pain.”

George W. Hayduke: “As earlier noted, might be higher pain tolerance threshold, stronger/more defined hip flexor areas, and lower centers of gravity, throw in statistically higher body fat %, and you have basic ingredients for traits ultra runners often seek/aspire to, IMHO.

Courtney Daulwater: “I have heard all sorts of scientific theories on all sides of the topic- none that stand out for me or that you wouldn’t have encountered in your own research. I’m not an expert on the topic, that’s for sure! I think that ultras test a lot of things in a person. Not only physical strength and endurance, but also the mental game, management of calories and hydration, and, sometimes, course logistics and organization of gear. When there are so many different factors, putting all the pieces together on race day is huge! When I race, I am focused on trying to nail as many of those factors as possible while out enjoying the sweet trails and incredible people of the ultra community. I am most competitive with myself… this includes trying to push my body and brain to see what is possible. Being competitive with myself also includes trying to chase down anyone in front of me, male or female. It’s all part of the fun of racing!

Aly Allen: “In my personal opinion, again with no scientific backing, I think women excel at ultra-distance running because at these distances it is no longer about a “power” it’s more about mental toughness and endurance.”

Mind over matter

Picking up on Aly’s point, I asked Sarah Cooke, RunUltra’s psychologist, what she thought:

Generally speaking, men still tend to be socialised to value speed, winning and gaining recognition whilst women are expected to be more social and less dominant. If we look at education, we also see that boys tend to favour exams which reward short-term and high intensity effort (cramming) and girls do well in coursework which requires a sustained level of moderate effort over time. I would be interested to see more research on this, but the camaraderie found in the ultra community and the value placed on going the distance regardless of time may appeal to women. The may also find it easier to adapt to the mentality of reducing short-term effort in order to sustain their performance, enabling them to gain long-term advantages. They may also respond better to the training demands of an ultra which requires time on feet more than high intensity workouts.”

Women’s wins

Whatever the reasons behind them, last year we saw some great female triumphs. British ultra runner, Jo Williams, triumphed at the Richtersveld Transfrontier Wildrun in June, winning the race with Tobias Mews coming in second. She took first place in the run with a fantastic time of 22.23.01 and Tobias Mews came in in second place and as first man with 22.42.00.

The 2016 Australia’s Big Red Run will be remembered by the dominant and outstanding performance of 2015 MDS ladies champion, Elisabet Barnes who won the race. Elisabet broke away on day 1 to win the stage outright, on day 2 under the harsh wet conditions she repeated the process and this scenario was echoed on day 5. Stage 4 was the only one she lost.  

Read more. 

Brilliant victories both but we do need to look at the results from UTMB, Marathon Des Sables, Western States et al, all of which were won by men with a healthy margin.

The science may be throwing up contradictory results and opinions may be divided, but one thing is clear. Women are putting in bravura performances in ultra running!

Thank you to all who contributed to this piece.

"During endurance exercise, fuel source and the use of it plays a primary role in performance. The contribution and expenditure of fat during exercise is regulated by several factors, including gender"

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