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Are You Training And Fueling Like A Small Man Versus A Woman?

An interesting look at a new book from Stacy Sims, who wants to talk about your period.

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“Women have periods and it’s okay to talk about it!”

That was Dr. Stacy Sims opening line, when I had the opportunity to talk with her about her new book, ROAR. The book is essentially a guide to understanding how to match your training cycles and fueling to your physiology as a female. If you think it doesn’t matter, keep reading.

Sims is an exercise physiologist and nutrition scientist who was also a competitive athlete and completed multiple Ironman races before officially retiring in October 2011. Sims realized there might be more women could be doing to train and race differently than men, way back when she was a high school girl on the crew team.

Related: Fueling Like A Lady

“I suspected something was different for us because our cycles linked up and we would have good weeks and not so good weeks at the same exact times.”

Any woman who has lived with another woman knows that your menstrual cycles will often align the longer you live together. The same was happening with Sims’ crew team except they could see the effect of high and low estrogen on their performance, even if they didn’t fully understand why yet.

One of the most intriguing and enlightening themes of ROAR is how Sims divides training cycles into high and low hormone phases and teaches you how to tailor your training to work with, instead of against, your body, according to these phases.

During what Sims describes as “low hormone phase”—the time during and immediately after your period—your physiology is most like that of a man, so racing with your period is actually a good thing. But, during “high hormone phases”—a few days before your period—things like building muscle, recovery and staying hydrated become much more difficult.

“Ironically you are most like a man when it comes to exercise, fueling and thermoregulation during your period and the follicular phase,” Sims explained “but it’s harder to hit high intensities and recover from hard exercise during the high-hormone phase.”

The good news? You can stop worrying about getting your period for a big race! Sims reminds us that Paula Radcliffe broke the world record for the fastest marathon in Chicago 2002 while she had menstrual cramps.

The overall solutions Sims offers us mortals to work with our female physiology is three-fold with dietary interventions, specifically timing your protein and hydrating correctly. The book includes extensive meal plans and hydration options in various chapters so you can literally plan your training, fuel and electrolyte needs around your 28-day cycle.

Other revelations include chapters on everything from pregnancy to menopause and how to accommodate your body’s changing needs during these different phases. There is a chapter on core strength, stability and mobility, complete with pictures of the training exercises executed to perfection and explanations of each in detail.

And, of course there is the chapter titled “Making Weight” dedicated to body image and how to eat right for the kind of body type you have and training required for your sport. It’s one of the most honest pieces I have read about female athletes and the relationship they have with their bodies.

“I have yet to meet a woman who has always had a healthy relationship with her weight,” Sims writes, “in fact, most women I’ve worked with, competed against, or just generally have gotten to know have had at least one period of disordered eating, if not a full blown eating disorder, in their lives” Sims confesses, “frankly, most women battle with their weight most of their lives – myself included.”

How’s that for honesty? She goes on to talk in detail about how important it is to eat right for optimum performance.

“There is no magic weight we should be and, athletes should be eating for performance!”

Sims still works with a lot of athletes and likes to ask them what the “goal” of exercise is. As Sims understands it (and she has a PhD in it) it’s to “stress your body until it almost breaks down but, it then has to build back up so, if you’re compromising what you’re eating then you’re not getting the full benefit.”

Sims went on to say that it was hard for her to understand as well “growing up in Kate Moss era” but athletes need to eat for their performance because, “if you don’t eat properly, your performance will reflect it.”

And, if you’re not training as a woman but a small man, your performance may reflect that as well.