Women have long been left on the sidelines in the area of scientific sports research, especially when it comes to how our bodies perform throughout our menstrual cycles. Why? The default answer is often that the female hormonal system is too complex to be properly studied. And yet this system, driven by estrogen and progesterone, influences our need for nutrition, hydration, activity and rest. Taking the menstrual cycle out of the equation when looking at athletic performance and training is a missed opportunity to optimize results. But thanks to a handful of female scientists, including Kelly McNulty, a Ph.D. candidate at Northumbria University in Newcastle, U.K., and founder of Period of the Period, an organization aimed at changing the narrative around women’s health and performance in sports, this area of study has increasingly become the subject of research. We spoke with McNulty about how to change the discourse on women’s health, understand the link between our cycles and our performance and, most importantly, listen to our bodies.

I have a theory that our life mission is sometimes born out of what made us suffer as a teenager. Do you agree?

“Absolutely. I’m studying the effects of menstrual cycles because when I played competitive golf, I was well aware that my cycle affected my performance even though no one talked to me about it. If the scientific evidence had been available at the time, I would have benefited from it [and been able] to overcome the challenges I was facing.”

What accounts for the lack of interest in the female hormonal system?

“In the 19th century, scientists discouraged women from any physical activity under the pretext that running or jumping could damage their reproductive organs. It wasn’t until the 1960s that the opportunity to participate in sports activities presented itself. That’s pretty recent, and while women’s presence in sports has increased in recent years to equal men’s, science still has some catching up to do. Another factor could be that there are more men than women working in sports and exercise science. But that’s no excuse. We need to do better.”

What are the different phases of the menstrual cycle?

“Let’s take a typical 28-day cycle. Day one is the first day of menstruation. At this time, estrogen and progesterone levels are at their lowest. Around day five, estrogen levels start to climb until they peak just before ovulation on day 11 or 12. Ovulation is the release of an egg and indicates the midpoint of the cycle. The next. phase involves a brief drop in estrogen before it climbs back up again as well as a rise in progesterone. If fertilization doesn’t occur, hormone levels drop again and a new cycle begins. The cycle can be summarized in two phases: the follicular phase, before ovulation, and the luteal phase, which follows ovulation.”

Where do we start if we want to move in rhythm with our cycles?

“This is a sometimes frustrating answer, but since the data is still limited, it’s important to read, question and analyze existing information. The next step is to track your cycle to get to know it. After all, our personal data is more valuable than data gathered about a group of women who might not be like us. The follicular phase seems to be the optimal time for strength and intensity training, but only four studies have presented these results, which is why it’s important to assess and explore what works best for each of us.”

How has analyzing and understanding your cycle affected your golf performance?

“There are studies that show that progesterone has a negative influence on the part of the brain that’s linked to coordination and precision, and I’ve noticed this myself: Alignment with my target is a skill that worsens slightly during my luteal phase. I have adapted my practice in order to be more successful. That’s the key: By knowing your cycle well, you can develop customized strategies. If you experience breast pain during your period but still want to work out, one strategy might be to choose a sports bra that offers greater support. If you notice high energy levels a few days before ovulation, take advantage of them to achieve your running goals.”

We live in a culture that focuses on performance consistency, but should we actually be listening to our body’s cyclical needs?

“Yes! The more we adapt to our cycles, the more we will see improvements and the more effective we will become, which could motivate us to practise gentler mobility movements or take the rest we need at key times of the month.”

What has made the greatest impact on you since beginning these studies?

“I started in this field with the preconception that certain phases of the menstrual cycle make women weaker and slower. This is not the case. Instead, I’ve learned that we are powerful, strong and fast throughout the month. Many world records and medals have been won by women during each phase of the menstrual cycle. So, the question is: Can we be even faster, stronger and more powerful? It’s not about being limited; [it’s about] using our physiology to feel better and get more out of our workouts.”

For more information on how your menstrual cycle affects your performance, check out these Instagram accounts: @periodoftheperiod, @_maisiehill (Period Power), @thewell_hq

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