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Sharpen Your Training By Understanding Your Unique Physiology

Doctor Stacy Sims advises on the best ways for women to use their physiology to their advantage in order to optimize running performance.

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Women are having a moment. We are doing things once thought impossible by coming together and expanding on what we believe we know to be true. In running specifically, women are breaking all kinds of barriers. From Shalane Flanagan’s epic New York City Marathon win to Molly Huddle’s crushing new American record in the half marathon, we are getting faster, stronger and smarter. The brains behind the operation is where Stacy Sims, Ph.D., comes in.

The author of what is for many female athletes something of a training bible, Sims wrote her book ROAR: How to Match Your Food and Fitness to Your Unique Female Physiology for Optimum Performance, Great Health, and a Strong, Lean Body for Life based on the concept that women are not small men–therefore, they should not follow the “shrink it and pink it” mentality when it comes to training. An accomplished triathlete herself, Sims knows all too well that training methodologies need to change where women are concerned.

Related: Stacy Sims Shares Why Fueling Like A Small Man Might Be Beneficial

Train Like A Woman

Recently, Sims shed some light on how to put this concept to the test and start training like a woman.

“The drive behind [the book] is the ongoing self-deprecation that women have–I’m not fit enough, I’m not hard enough, I’m failing my program, etcetera,” Sims said. “But it isn’t their fitness or their motivation; it is the fact that our physiology changes with hormone perturbations, and the status quo is to ignore that and train like men! Sex hormones have such huge influences on so many different aspects of the body, from endocrine and metabolic systems to fluid balance and thermoregulation; cognition, reaction times; macronutrient needs and utilization; recovery, sleep and immunity. Women need to know this to maximize their potential.”

Now you know. But what comes next?

Build Your Defenses

In the chapter “Demystifying Your Menstrual Cycle,” Sims discusses having an action plan for your period and recommends taking 250 milligrams of magnesium, 45mg of zinc and 80mg of aspirin plus 1 gram of omega-3 fatty acids each night for seven days before your period starts.*

“The actual bleeding is based upon an inflammatory response,” Sims explained. “By reducing the inflammation (all of these substances work on different cellular responses to reduce inflammation and fluid re-uptake), PMS and your period itself become less significant. It takes about three cycles for things to really settle, then it is almost like, Wow, okay–my period just started. Zinc levels fluctuate through the cycle as well, with serum levels dipping significantly in the luteal phase (zinc is needed for ovulation and to help follicles mature). Low zinc is associated with greater PMS symptoms–in particular, mood and fatigue.”

Boost Your Carb Intake

Another piece of supplemental advice Sims offers is that of increasing carbohydrate intake. Carbs are a hotly debated topic in our sport, so we were very interested in her advice to eat more carbs during the premenstrual part of one’s cycle.

“When estrogen rises, it reduces the body’s ability to access glycogen,” Sims said. “It essentially ‘spares’ carbohydrates and makes more free fatty acids available. For exercise, this impedes intensity and top end capacity. Thus greater cortisol is released to fuel the body. Elevated cortisol also impedes recovery (and progesterone is catabolic, which further impedes recovery). To maximize performance, taking on a bit more carbohydrates will allow a woman to hit the intensities she’s looking to hit, reduce cortisol production and keep the immune system from becoming depressed.”

Keep Track Of The Results

In ROAR, Sims suggests keeping a journal detailing one’s menstrual cycle. As many runners enjoy journaling almost everything, why not add this in and see if you detect a pattern?

“So many women kind of know when their cycle might start, but if you use an app (like FitrWoman), you can track your cycle and make notes on how you are feeling, what your performance is for that particular training session, [your] mood, etcetera,” Sims explained. “After three full cycles, you will know the pattern of responses you have against the particular phase of your cycle, so you can manipulate your training to maximize your body’s responses. Some women feel bulletproof in and around ovulation; others feel flat and tired. If you are [feeling] bulletproof, use that time to go and have a hard session. Remember that it is the training stress and subsequent adaptations that get us to our goals. If we work with our physiology instead of against it, we can most likely garner even more performance potential and supercede expectations.”

Sims added that runners should not be afraid to train in and around their menstrual cycles, explaining, “When it starts, it is because estrogen and progesterone have dropped and we are flying fast! The day before, the day of or the day after a woman’s period starts may be a bad day, but again, make notes of this and work from it. Women need to stop training and eating like men; we need to own our own unique physiology and see how far we can go! Who knows–women surpassing men in sports might happen sooner than we think.”

We think so, too.

*The author of this piece believes this method works because she tried it and it was a huge game changer in terms of energy, endurance and power during a tough training cycle.


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