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When Lonah Chemtai Salpeter of Israel touched down in Tokyo to run the Olympic marathon last week, she was prepared to run the race of her life. Months of training had put her in “my best shape ever,” she said.

“When you believe in your training and you see your training going well … you are all set,” the 33-year-old elite runner told The Lily. “I was not doubting myself.”

Salpeter, who originally hails from Kenya, had little reason to doubt herself: She holds Israeli national records in the marathon, the half-marathon and the 10,000-meter run, according to the international governing body World Athletics. And when she ran the Tokyo Marathon last March, Salpeter won the event in a race record of two hours, 17 minutes and 45 seconds.

But she was worried about one factor beyond her control at this year’s marathon: her period, which she said was slated to arrive two days before the race, and which she knew would probably impact her performance.

“I know myself — when I have my period, I don’t perform 100 percent,” Salpeter said.

Her period ultimately didn’t arrive until after the race, Salpeter said, but it nevertheless impacted her run. After setting off from the starting line, Salpeter remained in the lead pack for most of the 26.2 mile race. But with a few miles to go, her cramps got so bad that she stopped to take a break, she said. She wound up finishing in 66th place, in 2 hours, 48 minutes and 31 seconds — a far cry from the Top 3 finish she had hoped to achieve.

The day after the race, Salpeter posted on Facebook, writing that her period impacted her performance and that she was sharing her story to help dispel the stigma around athletes talking about menstruation and its impacts on their performance.

I cannot hide that I love challenges and I’m not someone who seeks excuses: my goal was to win my medal at the Olympic...

Posted by Lonah-Chemtai Salpeter on Saturday, August 7, 2021

“I think we really need to normalise the conversation around being female athletes,” she wrote.

Salpeter is not alone: A study of 15 women rugby players published last year found that nearly all of them reported experiencing menstrual-cycle-related symptoms while on their periods, and 67 percent thought those symptoms impacted their performances.

Experts say Salpeter’s experience is proof of how menstruation can directly impact athletic performance — and the crucial need to break the stigma around discussing it, in part to improve future research on it. That stigma can be especially tricky to navigate for transgender men and nonbinary people, among others, who also menstruate.

“Athletes don’t feel comfortable talking to their male coaches about it, and coaches don’t feel comfortable hearing about it, and it’s just kept as this thing that nobody talks about,” said Richard Burden, co-lead of female athlete health and performance at the English Institute of Sport, a governmental organization that supports elite athletes in the United Kingdom.

Gina Merchant, a San Diego-based runner, has long had intense cramps while exercising on her period, she said. Recently, she added, she has also started experiencing insomnia during her cycle — which she didn’t realize was common until she complained to a friend about how the lack of sleep was preventing her planned early morning runs, she said.

For Merchant, the lack of discussion around menstruation and its impact on athletics dates back to her college days, when coaches on both her track and soccer teams never brought it up.

“I was an athlete in two sports in college, and no one has ever talked to me about it,” said Merchant, 39, who works as a behavioral scientist. “It seems so obvious, you’re a women’s team. … How is it not discussed?”

It is not just open conversations that are lacking, according to Burden: There is also little research into how “female-specific challenges like the menstrual cycle can influence performance,” he said. “What ends up happening is you just superimpose male support onto female populations, and that just doesn’t cut it anymore.”

He and his colleagues at the English Institute of Sport are hoping to contribute to filling the gap in research with a pilot study, currently underway, that measures hormonal changes linked to menstruation in eight elite women athletes — some of whom competed in the Tokyo Olympics — competing in 15 sports, including soccer, tennis, rowing and gymnastics. (None of the participating athletes are transgender or nonbinary as far as Burden is aware, and none of the athletes include professional runners, he said.)

The study began two years ago and tracks athletes’ levels of oestradiol, a form of estrogen, and progesterone, a hormone released by the ovaries — two of the hormones that fluctuate with the menstrual cycle and drive physiological changes that can impact performance.

Both oestradiol and progesterone drop before the menstrual cycle begins, prompting an inflammatory response that triggers the shedding of the uterine lining that causes bleeding, according to Stacy Sims, a New Zealand-based athlete performance physiologist specializing in women’s physiology. The drop in hormones allows for a greater ability to access glycogen and fast twitch fibers, Sims said, adding that athletes can take advantage of this time in the early phase of their cycle to do higher-intensity training if they feel the urge.

“People shouldn’t be afraid to try to hit it hard” during this time, she said.

Hormone levels remain low during the bleeding phase, Sims said. Estrogen surges and then drops before and after ovulation, respectively, and both hormones increase about two days after ovulation and rise to a steady state before dropping at the beginning of the next cycle.

These fluctuations after the approximately 36-hour period of ovulation mean “your body isn’t resilient to stress,” Sims said. “This is where you want to do more steady state exercise and drop volume and intensity.”

The English Institute of Sport study is significant, according to Burden, in part because other studies have tended to offer generalized information based on tests of recreational athletes’ menstrual cycles — rather than those of elite athletes — over smaller periods of time. But while the general pattern of hormone fluctuations tends to remain the same among menstruators, hormone levels — and their impacts — can vary, making menstrual cycles “very individual, from both the physiology and the individuals’ experience,” Burden said.

“From one individual to the next it can be completely different, and even within one individual from one cycle to the next it can be completely different,” he added.

Studying individual athletes’ cycles over a longer period of time, and using that information to inform those athletes’ training and nutrition plans, is key to understanding how hormones linked to the menstrual cycle can impact energy levels and performance. That’s especially relevant for elite menstruating runners, who tend to experience high rates of menstrual irregularities, research shows.

For one professional tennis player participating in the study who had a history of amenorrhea, or the absence of menstruation for one or more menstrual cycles, the data and analysis gleaned from the study were able to help her understand how she should adjust her nutrition to better support her energy levels, and ultimately helped her menstrual cycles and hormonal fluctuations return to normal, Burden said.

In the years to come, the researchers hope to make the study more widely available to more elite and recreational athletes throughout the U.K. and test additional hormones — including cortisol and testosterone — to offer more specific insights around training and recovery, Burden said.

In the meantime, insights from the study — which researchers eventually hope to publish and share at academic conferences and through the media — will be relevant for the many athletes who “suffer from some of the same menstrual challenges that elite athletes do,” he noted.

Heather McLaughlin, a Philadelphia-based runner, said she is open about how her period impacts her runs with her running partners — including men, she said.

“So many of them have girlfriends, wives and daughters that deal with this, and they’ve said talking to me and listening to my soapbox rants help them understand it because it’s the sort of thing they’re never going to ask someone,” said McLaughlin, 32, an administrative coordinator.

When McLaughlin saw Salpeter share her story about having her period at the Olympic marathon, she was thrilled.

“I thought her speaking out was fantastic. More Olympians need to be open about this stuff,” she said. “But I also think that when we’re talking about it, we need to talk about it more broadly and inclusively. More than just females menstruate, and other parents than mothers menstruate.”

Salpeter knows she’s not alone, but she wishes more elite athletes would join her in speaking up about the impact their cycles have on their sports: “In races, I see some girls are suffering, but they only say, ‘My stomach is painful.’ I say, ‘Come on, I know [what you’re going through]' — I don’t even have to ask because I know how they feel,” she said.

In the meantime, she is buoyed by Burden’s research — which she’s not participating in or affiliated with — and hopes she can use some of its insights in preparing for the Paris Olympics.

The information “would not only help me, it would help others,” Salpeter said. “Nobody talks about [menstruation].”

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