CYCLE SYNCING IS TRENDY. DOES IT WORK?

Written by Alisha Haridasani Gupta

Professional athlete and fitness influencers say that timing workouts around their menstrual cycles has big benefits. Experts are less certain.

Among the many techniques that helped the U.S. women’s soccer team win the World Cup in 2019 was, according to one of the team’s coaches, a slightly unorthodox strategy: paying attention to the players’ menstrual cycles.

More than a year before the World Cup, the athletes began meticulously tracking their periods. Within months, “we noticed that around the first day of the cycle, some players were flagging,” said the coach, Dawn Scott. “It became clear that some players were having pretty bad period symptoms that were impacting recovery and ultimately performance.”

So the team strategized to work with their cycles, giving themselves more time to recover between workouts during the lower-energy phases, Ms. Scott said. She described how paying attention to these details allowed the players to perform their best even at the most sluggish times of the month. In the World Cup final, which Ms. Scott said came during the low-energy premenstrual phase of midfielder Rose Lavelle’s cycle, Ms. Lavelle nonetheless scored the winning goal against the Netherlands. Her period started the next day.

“People think, ah, it’s just female physiology, there’s nothing we can do about it,” Ms. Scott said. “But there is so much you can do.”

The practice of planning workouts around the menstrual cycle to optimize fitness results, known as “cycle syncing,” has permeated mainstream fitness, too. In 2021, the wearable fitness tracker Whoop introduced features to help women sync their workouts and cycles. Last summer, Nike started a cycle-informed program on its Training Club app. Google searches for the term “cycle syncing” have surged in the last year, and the same hashtag has attracted more than 294 million views on TikTok, where fitness instructors and influencers post workouts tailored to each cycle phase. Some women have shared that they’ve even shaped their work schedules around their cycles — by saying no to deadlines during low-energy phases, for example.

But the evidence on whether this training regimen works at enhancing fitness, let alone whether it helps in other parts of life, is too inconsistent to be convincing, experts said. At most, studies have confirmed what many women know instinctively: that the menstrual cycle corresponds with shifts in energy, mood and stress.

Much of the advice is also impractical, given that cycles vary from person to person and even from month to month, said Kathryn Clancy, a biological anthropology professor at the University of Illinois Urbana-Champaign who focuses on reproductive health.

Or, as she bluntly put it: “Are you measuring hormones every day? Do you actually know when your corpus luteum is producing the most progesterone? Probably not. That then poses the question: What are you syncing to?”

HOW CYCLE SYNCING IS SUPPOSED TO WORK

The average cycle lasts between 21 and 35 days and consists of four hormonally distinct phases: follicular, ovulation, luteal and menstruation (bleeding). The hormone shifts in each phase influence not just the reproductive organs but “almost every cell in the body,” said Dr. Shruthi Mahalingaiah, a fertility doctor at Massachusetts General Hospital and professor of environmental and reproductive health at Harvard T.H. Chan School of Public Health.

In the follicular phase, estrogen and follicle-stimulating hormone begin to rise, nudging the ovaries to nurture an egg for release and thickening the uterus for its arrival, Dr. Mahalingaiah said. According to proponents of cycle syncing, in this phase the body is primed to take on stress and can recover more quickly. Juliana Antero, a researcher at the French Institute of Sport, leads a program in the French sports ministry called Empow’her, which has been tailoring the training schedules of professional athletes to their cycles ahead of the 2024 Olympic Games. Ms. Antero said that, anecdotally, she has observed “a burst of energy” during this phase among athletes, which means they “are better at high-intensity training loads, they run faster, and they are more powerful.” As part of their personalized training regimen, the highest-intensity activities are scheduled during the follicular phase.

The egg’s release — ovulation — is followed by the luteal phase, characterized by high levels of the hormone progesterone, which is responsible for maintaining a stable environment in the uterus for a fertilized egg. The luteal phase can be associated with premenstrual syndrome symptoms, like bloating and low energy. In this window, the body may be better suited to lower-intensity activities with increased recovery time between workouts, said Stacy Sims, a sports and nutrition physiologist and former athlete who studies menstrual cycles and performance in professional athletes.

But cycles rarely follow supposedly typical patterns of peaks and troughs, said Dr. Clancy, who is also the author of “Period: The Real Story of Menstruation.” “If we look at the hormone cycles of hundreds of people, we don’t find anybody who looks like the textbook.” For example, some women skip ovulation for a few cycles or have multiple surges of estrogen. And it remains unclear whether cycle syncing makes sense for women using hormonal forms of birth control.

The bits of scientific and anecdotal evidence showing fluctuations in performance or energy throughout the menstrual cycle also don’t prove that syncing workouts to the cycle will optimize fitness. “From a medical standpoint, there is no good evidence,” said Dr. Asima Ahmad, a reproductive endocrinologist and the chief medical officer of a fertility benefits provider called Carrot Fertility. “It’s not something that I advocate for with my patients.”

Ms. Antero and Ms. Scott acknowledge the lack of research on the method, which they said is a symptom of a broader gap in research on women’s health. One of the main aims of the Empow’her program is to fill that void, Ms. Antero said. She plans to publish the results of the training program after the Olympics.

‘NOT FEASIBLE FOR THE EVERYDAY PERSON’

For the many women who aren’t training for a professional sporting event, just getting in a quick workout already feels like a monumental task without mapping it around the menstrual cycle, said Kelly Roberts, founder of the recreational running community Badass Lady Gang.

Ms. Roberts estimated that out of the more than 1,500 women she coached last year, only five had the time and schedule to accommodate cycle syncing. “It’s just not feasible for the everyday person,” she said.

People who have menstrual cycle irregularities because of polycystic ovary syndrome or premenstrual dysphoric disorder should talk to a doctor about the workout timing that would best help with their symptoms, said Ava Mainieri, former head of research at the women’s health care provider Tia.

“In the case of PCOS, for example, symptoms are so different woman to woman” that it’s hard to dictate hard and fast rules, she said. “And the added stress of needing to know exactly what week of your cycle you are in and what that means about working out” can be counterproductive.

The biggest upside of this trend, Dr. Mainieri said, is that it has increased “body literacy,” equipping women with information about how their cycles work.

“Now women are understanding that hey, I might be feeling this specific symptom during this time for this specific reason, so I’m going to be tender with myself,” she said. “That part is really lovely.”

📣 For more lifestyle news, follow us on Instagram | Twitter | Facebook and don't miss out on the latest updates!

2023-06-08T18:00:39Z dg43tfdfdgfd