CNN  — 

Hillary Clinton is on stage addressing the media, telling her audience she will take their questions when, mid-sentence, she yells: “Oh no, my period!”

Seconds later, in a manic high-pitched voice, Clinton, then the US Secretary of State, declares that her country should “nuke” England. It’s an unfortunate turn of events.

Five years on and Queen Elizabeth II and her subjects are, thankfully, still alive and well.

The big red button was never pressed, of course, as the on-screen meltdown was a scene in the American sitcom “30 Rock.” The show’s creator, Tina Fey, was mocking the perceived effect menstruation has on women. But periods can be a problem.

For elite athletes, gaining a better understanding of menstruation could be the difference between success and failure, be the difference between competing with confidence or competing with dread.

To help athletes and coaches gain a better grasp of how the menstrual cycle can affect training, performance and well-being, a PhD student in England has helped develop what has been described as a groundbreaking new app.

Launched in Boston this summer, the FitrWoman app has been downloaded all around the world, from Australia to the US and the Middle East. Co-creator Georgie Bruinvels describes the creation as a “no excuses app.”

“It provides people with an understanding and solutions about what they can do to reduce the impact [of the menstrual cycle],” Bruinvels, an elite runner who won the Manchester marathon in her first attempt at the distance, tells CNN Sport.

By inputting typical cycle length, period duration and the date of their last period, the app will calculate where the user is in their cycle and give daily, tailored, information on their physiology – what is happening to their body as a result of changes in their hormone levels – and also provide training and nutritional suggestions to reflect these changes.

How much of an impact could such information have on an elite athlete’s performance? In a world where coaches are ever searching for small, incremental improvements, it could be significant.

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Periods are often described as the “last taboo” in women’s sport. Though sportswomen have talked openly about menstruation in recent years it is only, says Bruinvels, a “handful” who speak out.

“People are starting to talk about it more, which is great, but no-one is really doing anything about it,” Bruinvels says. “What can we do to help athletes?”

According to BBC News, around 200 million people worldwide have downloaded period-tracking apps, some of the most popular are Clue, Glow and iPeriod Period Tracker, but FitrWoman focuses on maximizing sporting performance during the monthly cycle.

The FitrWoman app aims to help athletes train better

Bruinvels, a full-time sports scientist and researcher for the Irish sports and data company Orreco, developed the app with Grainne Conefrey, Orreco’s product development manager.

Ultimately, the sports enthusiasts are on a mission to pass on all that they have learned so that the prospect of young girls ditching sport, whatever their level, during puberty is diminished.

But, so far, the app’s main influence has been on the training and nutritional habits of elite and recreational athletes.

Bruinvels’ research paper on “Sports, exercise and the menstrual cycle,” published in the British Journal of Sports Medicine, serves as the foundation of the app’s expertise. Bruinvels and Conefrey also sent questionnaires to over 1,800 elite and recreational athletes to help gain a greater understanding of the impact menstruation has on performance.

From the questionnaires, the pair found that the menstrual cycle affected the training and performance of more than half of the elite athletes questioned, while it also impacted a third of the recreational athletes.

An example of the information available on FitrWoman

“During my research, I was finding more interesting information around the menstrual cycle,” says Bruinvels. “How it can affect performance and what can be done to reduce that, and what caution should be applied at certain times of the month.

“Athletes train for every eventuality, but they don’t train for their menstrual cycle.

“I know an athlete who competed in the Sydney Olympics and she said she came on her period the night before the race, because tapering, which is a reduction in training before big races, and flying can bring on a period. She was so underprepared that she didn’t know what to do.”

Curse or myth?

In 2015, British athlete Heather Watson blamed “girl things” on her first-round defeat at the Australian Open, while two-time Wimbledon champion Petra Kvitova has said periods could be “difficult” for females on the tennis tour.

British long jumper Jazmine Sawyer, who uses the FitrWoman app, pulled out of a competition in Boston this year because of period pain and, a few years ago, British middle-distance runner Jessica Judd admitted that her running times could vary by 15 seconds depending on what stage she is at in her cycle.

Paula Radcliffe is still the women's marathon world record holder.

But periods, though still clouded in euphemism, are certainly not a curse.

Paula Radcliffe first broke the women’s marathon world record in Chicago in 2002 on the first day of her period, though she did experience stomach cramps during the final third of the race.

A recent study, published in the journal Behavioral Neuroscience, found that women’s cognitive performance, specifically memory, attention and cognitive bias, was not altered by the hormonal changes which happen during the menstrual cycle.

But, in elite sport, research on the impact periods have on different athletes is limited.

However, there is evidence to suggest women could be more susceptible to injury at different points of their monthly cycle as tendons and ligaments become lax and elastic around the time of ovulation, due to oestrogen levels being at their peak.

Anne Keothavong is a former British No.1 tennis player.

Anne Keothavong’s tennis career was one troubled by knee injuries sustained when the former top-50 player was menstruating.

Adapting training regimes could prevent injuries, says Bruinvels.

“Risk of injuries, like anterior-cruciate ligament or other soft tissue ligaments, is increased when oestrogen levels are high just before ovulation,” she explains.

“When you have high levels of oestrogen, it means stability is affected.

“The most important thing is understanding. They need to have physiological awareness of why. There are certain times of the month when you are stronger so you can lift heavy weights, but there are certain times, to get the same benefits, you don’t have to lift those heavy weights.

“The best thing we’ve had is athletes saying ‘if only we had your app, we wouldn’t have the injury problems I have now.’

“The injury risk is huge, especially in team sports like football and rugby.”

Women do not always have to lift heavy weights, says Brunivels, to get maximum benefit from training.

If athletes train smarter, focusing on endurance when oestrogen and progesterone levels are starting to increase, switching to high intensity and resistance routines when oestrogen is high and progesterone is low just before ovulation, then, says Bruinvels, the risk of injury will decrease.

As well as giving information on when to lift or stretch or run, the app also informs users about what to eat and when – iron and carbohydrates during menstruation, for example, healthy fats towards the end of the cycle.

Heat and humidity can affect an athlete during her period, too, because hormonal imbalance can cause the body’s core temperature to slightly rise.

But there are solutions: hydrating before and during exercise, and drinking sodium-based electrolyte drinks to make sure the fluid is absorbed.

Whey shakes and fish oils, says the app, can reduce anxiety and stress during a period, while it advises users to eat protein with every meal during menstruation: “Protein and slow carbohydrates will help maintain your energy levels, stabilize blood sugars and reduce cravings.”

“When you’re pre-menstrual your blood sugar is more likely to fluctuate so we recommend foods to counter that and eating regularly,” Bruinvels explains.

Learning to train like women

Hormonal fluctuation makes it more complex to study women rather than men.

During a typical 28-day cycle, a woman’s hormone levels will change daily, which is why it was historically men, rather than women, who were tested for medical research.

“Around the time of the first and second world wars, due to potential harm to unborn fetuses, it was decided that research should be done on men and not women,” explains Bruinvels.

“More latterly, it’s been appreciated that women are different and that women have cyclical hormonal fluctuation, making them more complex to study than men, and way more expensive.

“Typically, when research is conducted in women, it’ll be when they’re bleeding, which is when their hormone levels are low and therefore most similar to men, or on women who are on the contraceptive pill, or studies just ignore the menstrual effects and don’t consider it at all, which is catastrophic.”

It is still, it seems, a man’s world.

screenshot period women talk orig vid ms
Women talk: Paging 'Aunt Flo'
01:07 - Source: CNN

During a recent lecture before around 400 tennis coaches, Bruinvels was shocked to learn the largely male crowd did not know about the physiological differences between men and women.

It led Bruinvels to ask: what if these male coaches helped women train like women? Would, she wondered, more world records be broken if everyone was better informed, if training was smarter?

After all, only an athlete at ease with herself and her “invisible troubles” has the bombast to train and perform like a great.

“Men and women are very different. Physiologically they’re different, they shouldn’t train the same,” she says.

“I would say men are keen to learn, but where do they find that information? How do they access it?

“Some of the coaches said they already change the training to the girls’ needs, but they don’t really know how or what that looks like.

“We have a coach who we work with regularly and he would say how one of his athletes would have two days every month where she couldn’t compete. It was just accepted. The need for understanding from the coach’s perspective is huge and that’s the biggest thing that’s been highlighted.”

Data, drinking, eating – influencing performance

Bruinvels and Conefrey’s app is still in its infancy and so to help with development they have been working closely with Celtic Women’s football team. Currently half the Glaswegian team’s squad use the app, with the club’s sports scientists keeping a close eye on results.

Some members of Celtic Women's football team have been using FitrWoman.

“It gives the players autonomy,” Andrew Wiseman, Celtic Women’s athletic development coach, tells CNN Sport.

“We very much encourage them to take the reins. It makes them more aware of the influence of the cycle on performance.

“Performance is such a big thing. There are so many factors that can influence it. It certainly has had its benefits for us.

“We collect data every day. If I was to look back over two or three months of data and can’t work out why that person isn’t performing, if we can’t pinpoint anything, we do now have an alternative and we’ll ask that player: can we have a look if you’re using the app.”

Since using the app, Celtic Women’s captain Kelly Clark, a trainee accountant, has noticed she has more energy to perform after a day in the office.

“Before the app, I’d just blame work for everything,” she tells CNN Sport.

“I’d just think to myself ‘I’ve worked hard this week so maybe that’s why I feel tired.’ I didn’t think it could be anything to do with the menstrual cycle. It’s reassuring at times to know that that’s probably the way I should be feeling.

“There was one day at work when I drank two liters of water throughout the day, but I was still thirsty. I didn’t understand why so I checked the app and it said ‘make sure you drink enough water today.’ That day it was so on-point that I began to take it more seriously.

“I’ve never focused on hydration and nutrition as much as I do now and this season is the fittest I’ve been. It could be down to the app, it could be down to training, but it’s probably a combination of both.”

Clark admits that menstruation is still a subject the squad rarely talks about, although teammates with history of anterior cruciate ligament (ACL) injuries have spoken of the benefits of having an easily accessible reference point.

“For the players who had done their ACLs, the app reassured them that they could really push themselves in training. It really helped mentally,” says the Scot.

“Because football is a team sport you can’t completely change training sessions for one person. But if it’s proven that during certain times of the month you need to be more careful, we should all have access to that information.

“In football especially, there are a lot of male coaches and it’s an area they don’t want to speak about, but this information has probably forced that upon them.”

What next for Bruinvels and Conefrey? They have already embarked on the second part of their project, asking more questions to hundreds of women, making plans to update the app to accommodate the fresh information at their disposal.

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“We’ve lots of plans,” Conefrey tells CNN Sport, her eyes widening.

“This is just our first version of it. It’s about sharing information and giving it to a wider audience. We want to build an app that takes everything into account for the female athlete and will then generate its own data.

“We asked the question whether anyone altered their training and nutrition and the answer was ‘no.’ Then we asked do they want to and the answer was ‘yes.’ But if you Google it, there’s no information on how to do this.

“You don’t want to go into that quarterfinal thinking ‘oh crap, I’m on my period’. I definitely want to change that mindset.”